Journal articles: 'Cracking intensity'

1

Yang, Bin, Qin Shou Huang, Xin Wang Qiu, and Hua Xu. "Dynamic Response Analysis of Stress Intensity Factors of Reflective Cracking in Asphalt Overlay Suffer Wheel Load." Advanced Materials Research 217-218 (March 2011): 187–90. http://dx.doi.org/10.4028/www.scientific.net/amr.217-218.187.

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Partial wheel loading of the existing old cement concrete pavement joint will easily causes shear-type reflective cracking of asphalt overlay, which will cut down the service life of the pavement. This paper conducts an research on the changing rules of stress intensity factors of reflective cracking in asphalt overlay suffer dynamic loads. Choose 3 asphalt overlays with typical reflective cracking extend length of 1cm, 4cm and 8cm to investigate the impacts of parametric variation of vehicle speed, asphalt overlays thickness and modulus and stress absorbing layer on stress intensity factors of reflective cracking in asphalt overlays suffer singe-wheel dynamic loads. Results show that time history curves of dynamic stress intensity factors declines with the increase of structure-layer parameters; the maximum amplitude decreases as time goes on; the larger the structure parameter is, the faster the degradation is; and the vibration levels to gentle in the later half period, but stress intensity factors are not equal to zero in the last period of vibration, which shows that there exists residual stress intensity factors.

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2

Fang, Qiang. "A Comparative Study of Delayed Hydride Cracking in Zr-3.5Sn-0.8Nb-0.8Mo and Zr-2.5Nb." Materials Science Forum 917 (March 2018): 207–11. http://dx.doi.org/10.4028/www.scientific.net/msf.917.207.

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A new test procedure for measuring the resistance to delayed hydride cracking was developed. The critical stress intensity factors for delayed hydride cracking and the crack growth velocities of Zr-3.5Sn-0.8Nb-0.8Mo alloy with different heat treatments were evaluated and compared with Zr-2.5Nb. It was found that Delayed Hydride Cracking (DHC) crack growth velocity increases with the alloy strength, and the critical stress intensity factor is independent of heat treatment history or alloy composition.

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Sun, Jiamin, Jonas Hensel, Thomas Nitschke-Pagel, and Klaus Dilger. "Influence of Restraint Conditions on Welding Residual Stresses in H-Type Cracking Test Specimens." Materials 12, no. 17 (August 23, 2019): 2700. http://dx.doi.org/10.3390/ma12172700.

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From the viewpoint of mechanics, weld cracking tends to occur if the induced tensile stress surpasses a certain value for the particular materials and the welding processes. Welding residual stresses (WRS) can be profoundly affected by the restraint conditions of the welded structures. For estimating the tendency of weld cracking, the small-scale H-type slit joints have been widely used for cracking tests. However, it is still hard to decide whether the real large-scale component can also be welded without cracking even though the tested weld cracking specimens on the laboratory scale can be welded without cracking. In this study, the intensity of restraint which quantitatively indicates how much a joint is restrained is used. The influence of restraint condition (intensity of restraint) on WRS is systematically investigated using both the numerical simulation and the experimental method. The achievement obtained in the current work is very beneficial to design effective H-type self-restrained cracking test specimens for evaluating the sensitivity of the material and the welding procedures for weld cracking in the real large-scale components.

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Sekine, Hideki, and Peter W. R. Beaumont. "Stress-Corrosion Cracking in Unidirectional GFRP Composites." Key Engineering Materials 430 (March 2010): 101–13. http://dx.doi.org/10.4028/www.scientific.net/kem.430.101.

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A micromechanical theory of macroscopic stress-corrosion cracking in unidirectional glass fiber-reinforced polymer composites is proposed. It is based on the premise that under tensile loading, the time-dependent failure of the composites is controlled by the initiation and growth of a crack from a pre-existing inherent surface flaw in a glass fiber. A physical model is constructed and an equation is derived for the macroscopic crack growth rate as a function of the apparent crack tip stress intensity factor for mode I. Emphasis is placed on the significance of the size of inherent surface flaw and the existence of matrix crack bridging in the crack wake. There exists a threshold value of the stress intensity factor below which matrix cracking does not occur. For the limiting case, where the glass fiber is free of inherent surface flaws and matrix crack bridging is negligible, the relationship between the macroscopic crack growth rate and the apparent crack tip stress intensity factor is given by a simple power law to the power of two.

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5

Li, Limin, Zhaoyang Guo, Longfei Ran, and Jiewen Zhang. "Study on Low-Temperature Cracking Performance of Asphalt under Heat and Light Together Conditions." Materials 13, no. 7 (March 27, 2020): 1541. http://dx.doi.org/10.3390/ma13071541.

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The low-temperature cracking performance of asphalt is considered one of the main deteriorations in asphalt pavements. However, there have been few studies on the low-temperature cracking performance of asphalt under heat and light together. Hence, the ductility test, bending beam rheometer (BBR) test, and asphalt composition analysis test are combined to investigate the low-temperature cracking performance under heat and light together based on the climatic conditions of China. The styrene–butadiene–styrene block copolymer (SBS)-modified asphalt binders were prepared with different modifier types and base asphalt in this research. The results show that the low-temperature cracking resistance of asphalt reduces under heat and light together. It is obviously reduced at the early stage, and it becomes worse with the increase of the aging time, temperature, and ultraviolet (UV) intensity. The asphalt composition has a significant impact on its low-temperature cracking performance, and the SBS modifier can improve the low-temperature cracking resistance of asphalt. The rational selection of base asphalt and modifier can improve the low-temperature cracking performance of asphalt. Under heat and light together, whether base asphalt or modified asphalt, the change trends of their ductility and component content are similar. Therefore, to improve the anti-cracking ability of the asphalt pavement, it is suggested to use the ductility of asphalt aged by heat and light together for 15 days as the evaluation index of the low-temperature cracking performance of asphalt, and asphalt should be selected according to the temperature and UV intensity of the asphalt pavement use area.

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6

Uzan, Jacob. "Evaluation of Fatigue Cracking." Transportation Research Record: Journal of the Transportation Research Board 1570, no. 1 (January 1997): 89–95. http://dx.doi.org/10.3141/1570-11.

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The continuous growth of damage from fatigue cracking is described as a two-stage process of crack initiation and crack propagation. The crack-initiation stage can be characterized by conventional laboratory fatigue tests. The crack-propagation stage is described using the Paris-Erdogan phenomenological law. Problems encountered in implementing the theory are presented and discussed. For the sake of simplicity, only Mode II (shearing mode of the crack tip) is used. Computations of the stress-intensity factors and of the number of load repetitions for propagating the crack are presented. The applicability of the above fracture approach is evaluated using a pavement design method that includes an additional term to represent the crack-propagation phase.

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Mackay, T. L., and B. J. Alperin. "Stress intensity factors for fatigue cracking in high-strength bolts." Engineering Fracture Mechanics 21, no. 2 (January 1985): 391–97. http://dx.doi.org/10.1016/0013-7944(85)90027-x.

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8

YU, G., B. JIANG, L. QIAO, Y. WANG, and W. CHU. "Threshold stress intensity for hydrogen—Induced cracking of tubular steel." Scripta Materialia 36, no. 12 (June 15, 1997): 1467–70. http://dx.doi.org/10.1016/s1359-6462(97)00037-7.

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9

Sura, V., and S. Mahadevan. "Modelling shattered rim cracking in railroad wheels." Proceedings of the Institution of Mechanical Engineers, Part F: Journal of Rail and Rapid Transit 225, no. 6 (June 1, 2011): 593–604. http://dx.doi.org/10.1177/0954409711403671.

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Shattered rim cracking, propagation of a subsurface crack parallel to the tread surface, is one of the dominant railroad wheel failure types observed in North America. This crack initiation and propagation life depends on several factors, such as wheel rim thickness, wheel load, residual stresses in the rim, and the size and location of material defects in the rim. This article investigates the effect of the above-mentioned parameters on shattered rim cracking, using finite element analysis and fracture mechanics. This cracking is modelled using a three-dimensional, multiresolution, elastic–plastic finite element model of a railroad wheel. Material defects are modelled as mathematically sharp cracks. Rolling contact loading is simulated by applying the wheel load on the tread surface over a Hertzian contact area. The equivalent stress intensity factor ranges at the subsurface crack tips are estimated using uni-modal stress intensity factors obtained from the finite element analysis and a mixed-mode crack growth model. The residual stress and wheel wear effects are also included in modelling shattered rim cracking. The analysis results show that the sensitive depth below the tread surface for shattered rim cracking ranges from 19.05 to 22.23 mm, which is in good agreement with field observations. The relationship of the equivalent stress intensity factor (Δ K eq) at the crack tip to the load magnitude is observed to be approximately linear. The analysis results show that the equivalent stress intensity factor (Δ K eq) at the crack tip depends significantly on the residual stress state in the wheel. Consideration of as-manufactured residual stresses decreases the Δ K eq at the crack tip by about 40 per cent compared to that of no residual stress state, whereas consideration of service-induced residual stresses increases the Δ K eq at the crack tip by about 50 per cent compared to that of as-manufactured residual stress state. In summary, the methodology developed in this article can help to predict whether a shattered rim crack will propagate for a given set of parameters, such as load magnitude, rim thickness, crack size, crack location, and residual stress state.

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10

Miyajima, Tatsuya, and Mototsugu Sakai. "The fracture toughness for first matrix cracking of a unidirectionally reinforced carbon/carbon composite material." Journal of Materials Research 6, no. 11 (November 1991): 2312–17. http://dx.doi.org/10.1557/jmr.1991.2312.

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The fracture toughness for first matrix cracking of a uniaxially reinforced C-fiber/C-matrix composite is investigated using a modified controlled surface flaw method. The theoretical models for first matrix cracking of brittle matrix composites including the stress intensity and the potential energy approaches are reviewed in the light of the experimental results. The sharing of the applied load between the reinforcing fibers and the brittle matrix along with extensive crack front debonding enhance the fracture toughness for first matrix cracking.

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11

Luo, Yuhu, Bo Tian, and Kaimin Niu. "Numerical Analysis of Reflective Cracking of Continuous Reinforced Composite Pavement under Multifactor Coupling." Mobile Information Systems 2021 (October 18, 2021): 1–18. http://dx.doi.org/10.1155/2021/7065124.

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The occurrence and expansion of reflective cracking is a typical problem associated with the composite pavement that has a proven impact on the life of the continuous reinforced composite pavement. The current research studies a 3D finite element model to preset cracks at the top of the continuously reinforced concrete (CRC) layer’s transverse crack and at the bottom of the asphalt concrete (AC) layer based on the theory of linear elastic fracture mechanics in order to explore the factors responsible for the reflective cracking formation mechanism and expansion law. Considering the main stress parameters that affect the formation of reflective cracking (layer bottom tensile stress and vertical shear stress), the most unfavorable load position and the most unfavorable point of the corresponding stress parameter are determined that are then used to calculate the stress intensity factor of the crack tip under the coupling effect of multiple factors based upon the position and point above the crack, by using the confinement integral. The variance analysis of the stress intensity factor of the crack tip under the multifactor coupling effect is conducted via an orthogonal test in order to determine the main factors affecting the formation and development of reflective cracking. Meanwhile, the analysis of single-factor sensitivity is carried out on all these factors, which reveal the real contribution in the formation and expansion of reflective cracking in the continuous reinforced composite pavement. The results show that the most unfavorable load position for reflective cracking is when the load is on the side of the CRC layer’s lateral crack, while the most unfavorable point of the stress parameter is concentrated within the range of the wheel track. At the same time, analysis of multifactor variance and that of single-factor sensitivity show that the cracking mode of reflective cracking in the continuous reinforced composite pavement is a mixed one, dominated by K2 (slip type), supplemented by K1 (open type), and participated by K3 (tear type), whereas the AC layer’s preset-crack depth ratio, instantaneous temperature drop, and CRC-transverse-crack load transfer capacity are the main factors that affect the formation and development of the reflective cracking. Moreover, a better bonding state between the AC layer and the CRC layer improves the stress intensity factor of the preset crack tip on the bottom of the AC layer.

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12

Qiu, Shi, Wenjuan Wang, and Kelvin C. P. Wang. "A comprehensive system for AASHTO PP67-10 based asphalt surfaced pavement cracking evaluation." Canadian Journal of Civil Engineering 43, no. 3 (March 2016): 260–69. http://dx.doi.org/10.1139/cjce-2014-0519.

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In light of the newly released AASHTO cracking protocol PP67-10 and high quality cracking data produced from a novel 3D 1 mm pavement data collection and automated analysis system, this paper develops an index system for overall cracking evaluation. The Analytical Hierarchy Process (AHP) is employed to establish a general framework and fuzzy set theory is adopted to convert actual severity and intensity measures into normalized scores. Multiple data combination techniques are applied for data aggregation. The ultimate product of this system, a single number cracking index representing the overall cracking condition, can be used to rank pavements and prioritize crack-oriented maintenance and rehabilitation projects. Furthermore, cracking indices for different pavement zones can also be derived from the system, which would be significant to examine the pavement failure mechanism. A case study containing 10 pavement sections is performed to demonstrate the applicability of this proposed evaluation system.

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13

Solov’ev, S. A., and O. V. Yarygina. "RELIABILITY ANALYSIS OF REINFORCED CONCRETE FLEXURAL ELEMENT ON CRACKING BASED ON FRACTURE MECHANICS." Spravochnik. Inzhenernyi zhurnal, no. 283 (October 2020): 40–44. http://dx.doi.org/10.14489/hb.2020.10.pp.040-044.

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The article describes a probabilistic approach to the reliability analysis of a flexural reinforced concrete element by the cracking criterion using the provisions of fracture mechanics. Two mathematical models of limit state are proposed for reliability analysis: with the evaluation of the critical stress intensity coefficient directly and through the design concrete compressive strength. On the basis of regression analysis, the relationship between the critical stress intensity coefficient and the design concrete compressive strength is established which can be used in the inspection of reinforced concrete structural elements. The influence of the design concrete compressive strength on the failure (cracking) probability of the flexural reinforced concrete element is analyzed. The numerical example of reliability analysis is given for the reinforced concrete beam by the criterion of cracking. It is noted that the required level of reliability should be set for each structural object individually based on the acceptable risk value using economic and non-economic losses.

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14

Solov’ev, S. A., and O. V. Yarygina. "RELIABILITY ANALYSIS OF REINFORCED CONCRETE FLEXURAL ELEMENT ON CRACKING BASED ON FRACTURE MECHANICS." Spravochnik. Inzhenernyi zhurnal, no. 283 (October 2020): 40–44. http://dx.doi.org/10.14489/hb.2020.10.pp.040-044.

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The article describes a probabilistic approach to the reliability analysis of a flexural reinforced concrete element by the cracking criterion using the provisions of fracture mechanics. Two mathematical models of limit state are proposed for reliability analysis: with the evaluation of the critical stress intensity coefficient directly and through the design concrete compressive strength. On the basis of regression analysis, the relationship between the critical stress intensity coefficient and the design concrete compressive strength is established which can be used in the inspection of reinforced concrete structural elements. The influence of the design concrete compressive strength on the failure (cracking) probability of the flexural reinforced concrete element is analyzed. The numerical example of reliability analysis is given for the reinforced concrete beam by the criterion of cracking. It is noted that the required level of reliability should be set for each structural object individually based on the acceptable risk value using economic and non-economic losses.

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15

Sharma, Hemanti, Sebastian G. Mutz, and Todd A. Ehlers. "The effects of late Cenozoic climate change on the global distribution of frost cracking." Earth Surface Dynamics 10, no. 5 (October 25, 2022): 997–1015. http://dx.doi.org/10.5194/esurf-10-997-2022.

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Abstract. Frost cracking is a dominant mechanical weathering phenomenon facilitating the breakdown of bedrock in periglacial regions. Despite recent advances in understanding frost cracking processes, few studies have addressed how global climate change over the late Cenozoic may have impacted spatial variations in frost cracking intensity. In this study, we estimate global changes in frost cracking intensity (FCI) by segregation ice growth. Existing process-based models of FCI are applied in combination with soil thickness data from the Harmonized World Soil Database. Temporal and spatial variations in FCI are predicted using surface temperature changes obtained from ECHAM5 general circulation model simulations conducted for four different paleoclimate time slices. Time slices considered include pre-industrial (∼ 1850 CE, PI), mid-Holocene (∼ 6 ka, MH), Last Glacial Maximum (∼ 21 ka, LGM), and Pliocene (∼ 3 Ma, PLIO) times. Results indicate for all paleoclimate time slices that frost cracking was most prevalent (relative to PI times) in the middle- to high-latitude regions, as well as high-elevation lower-latitude areas such the Himalayas, Tibet, the European Alps, the Japanese Alps, the US Rocky Mountains, and the Andes Mountains. The smallest deviations in frost cracking (relative to PI conditions) were observed in the MH simulation, which yielded slightly higher FCI values in most of the areas. In contrast, larger deviations were observed in the simulations of the colder climate (LGM) and warmer climate (PLIO). Our results indicate that the impact of climate change on frost cracking was most severe during the PI–LGM period due to higher differences in temperatures and glaciation at higher latitudes. The PLIO results indicate low FCI in the Andes and higher values of FCI in Greenland and Canada due to the diminished extent of glaciation in the warmer PLIO climate.

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16

Hall, M. M. "Effect of Variable Stress Intensity Factor on Hydrogen Environment Assisted Cracking." Metallurgical and Materials Transactions A 42, no. 2 (May 29, 2010): 304–18. http://dx.doi.org/10.1007/s11661-010-0226-2.

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Wang, Bao-Lin, and Jing Li. "Thermal stress and intensity release in ferroelectric materials by multiple cracking." Acta Materialia 53, no. 3 (February 2005): 785–99. http://dx.doi.org/10.1016/j.actamat.2004.10.031.

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18

Chen, Song Zhou. "The Application of Fracture Mechanics in Highway Tunnel Lining Cracking." Applied Mechanics and Materials 580-583 (July 2014): 1377–81. http://dx.doi.org/10.4028/www.scientific.net/amm.580-583.1377.

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Lining cracks of highway tunnel has a very important effect on the healthy operation of the tunnel. Establishing the model for concrete fracture mechanics evaluation, we could identify the tunnel lining cracking situation. By using Linear elastic fracture mechanics method we could calculate the stress field of crack in the lining. Separately by different depth we have calculated crack stress intensity factor. We get that growing rates of variation of stress intensity factor as the crack depths increase. So lining tunnel health operations severely cracked.

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Serna, Sergio, Julio C. Villalobos, Osvaldo Flores, Horacio Martínez, Edgar López, and Bernardo Campillo. "Efecto del H2S en la Susceptibilidad al Agrietamiento de Dos Aceros Microaleados para Tubería." KnE Engineering 3, no. 1 (February 11, 2018): 424. http://dx.doi.org/10.18502/keg.v3i1.1447.

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Cracking in sour media modes were observed, and these were related mainly to the microstructure produced during the thermomechanical process of two microalloyed steels grade API X 52. Through the use of linear elastic fracture mechanics modified specimens. Steels loaded at similar initial stress intensity factors showed different cracking modes that were related directly to their different microstructures. Steels microstructures indicate different fabrication routes. Testing temperature played an important role on switching the cracking characteristics being remarkable by the ferrite-pearlite steel microstructure. A banded microstructure is susceptible to the effects of hydrogen at room T. While, an acicular ferrite microstructure with carbides patches at grain boundaries is susceptible to anodic dissolution in front of the crack tip, no matter the temperature being tested. Key words: microalloyed steels, sour service, cracking modes, microstructure.

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20

DASOG, G. S., D. F. ACTON, A. R. MERMUT, and E. DE JONG. "SHRINK-SWELL POTENTIAL AND CRACKING IN CLAY SOILS OF SASKATCHEWAN." Canadian Journal of Soil Science 68, no. 2 (May 1, 1988): 251–60. http://dx.doi.org/10.4141/cjss88-025.

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Clay soils in Saskatchewan were studied to understand their shrink-swell potential, to identify soil properties that predict the coefficient of linear extensibility (COLE), and to assess the extent of cracking during the growing season. The soils have medium to very high shrink-swell potential, which is related to the specific surface area associated with expandable clays. Because expandable clays in these soils are predominantly of fine clay size, COLE is reasonably well predicted from percent fine clay. The extent of cracking is estimated for some sites using an improved method of measurement. Limited data suggest that cracking intensity in native grassland is less than in cultivated sites and that, under wheat, it is more pronounced in subarid than in subhumid sites. The magnitude of cracking in clay soils of Saskatchewan is much lower than in warmer regions of the world. It is suggested that COLE values and the extent of cracking could be used in improving the classification of clay soils. Key words: Clay soils, COLE, shrink-swell potential, shrinkage, cracking, Saskatchewan

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21

Lee, Gi-Bum, Seung-Hyun Park, Youn-Young Jang, Nam-Su Huh, Sung-Hoon Park, Noh-Hwan Park, and Jun Park. "Development of Automatic Crack Growth Simulation Program Based on Finite Element Analysis." Applied Sciences 12, no. 6 (March 17, 2022): 3075. http://dx.doi.org/10.3390/app12063075.

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A crack growth simulation program based on the advanced iterative-finite element method (AI-FEM) was developed to predict realistic crack growth of structures. The developed program was suggested to calculate the exact stress intensity factor for arbitrary structures by regenerating the crack tip mesh as the crack grows. The main advantages of the developed program are to estimate each different crack growths along the crack tip line and to simulate the cracking transition from a surface crack to a through-wall crack under a complex stress field. For these purposes, the sensitivity analyses were performed for various influence variables on stress intensity factors, such as element types and crack dimensions. Based on the results of sensitivity analyses, the appropriate criteria for crack tip modeling to be used in AI-FEM were suggested to calculate sufficient converged SIF. The program developed in this research was validated through stress corrosion crack growth and natural crack growth examples including cracking transition, and it was confirmed that the program simulates crack growth well and has reasonable methods for cracking transition.

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22

Kasul, David B., and Lloyd A. Heldt. "Environmental Effects on the Cracking of Engineering Materials." MRS Bulletin 14, no. 8 (August 1989): 37–43. http://dx.doi.org/10.1557/s0883769400061947.

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A material's susceptibility to cracking may be significantly affected by its chemical environment. Stress corrosion cracking (SCC), liquid metal embrittle-ment (LME), hydrogen embrittlement (HE), and corrosion fatigue are examples of environmental effects which cause ductility or endurance losses through environment-assisted cracking (EAC). Under certain conditions, virtually all commercially important materials are susceptible to one or more of the above embrittlement processes. Cracking may occur intergranularly, transgranularly, or in a mixed mode, depending on conditions. Much is known about the metallurgical and environmental conditions which promote environment-assisted cracking, and prudent control of these is often successful in mitigating or preventing cracking. However, in spite of our understanding of the factors controlling SCC, LME, and HE, the responsible mechanisms remain elusive.This article will (1) review some of the important variables affecting these phenomena, such as stress, stress intensity, material microstructure, strain rate, electrochemical potential and pH, and (2) attempt to relate phenomeno-logical characteristics of environment-induced embrittlement to several mechanisms proposed for environment-assisted cracking, as they are understood today.The problem of stress corrosion cracking is unquestionably the most costly of environmental cracking phenomena, with losses occurring in a wide variety of service environments. Liquid metal embrittlement is of concern in nuclear power and other industries. Hydrogen embrittlement, first recognized as an embrittler of iron in 1873, causes cracking problems in applications ranging from welding to oil drilling. In all, the list of situations in which environment-assisted cracking occurs is long and is likely to grow as materials are increasingly challenged by the severity of their service conditions.

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Busse, Christian, Frans Palmert, Paul Wawrzynek, Björn Sjödin, David Gustafsson, and Daniel Leidermark. "Crystallographic crack propagation rate in single-crystal nickelbase superalloys." MATEC Web of Conferences 165 (2018): 13012. http://dx.doi.org/10.1051/matecconf/201816513012.

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Single-crystal nickel-base superalloys are often used in the hot sections of gas turbines due to their good mechanical properties at high temperatures such as enhanced creep resistance. However, the anisotropic material properties of these materials bring many difficulties in terms of modelling and crack growth prediction. Cracks tend to switch cracking mode from Mode I cracking to crystallographic cracking. Crystallographic crack growth is often associated with a decrease in crack propagation life compared to Mode I cracking and this must be taken into account for reliable component lifing. In this paper a method to evaluate the crystallographic crack propagation rate related to a crystallographic crack driving force parameter is presented. The crystallographic crack growth rate is determined by an evaluation of heat tints on the fracture surface of a specimen subjected to fatigue loading. The complicated crack geometry including two crystallographic crack fronts is modelled in a three dimensional finite element context. The crack driving force parameter is determined by calculating anisotropic stress intensity factors along the two crystallographic crack fronts by finite-element simulations and post-processing the data in a fracture mechanics tool that resolves the stress intensity factors on the crystallographic slip planes in the slip directions. The evaluated crack propagation rate shows a good correlation for both considered crystallographic cracks fronts.

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Padmanabhan, R., and W. E. Wood. "Stress Corrosion Cracking Behavior of 300M Steel under Different Heat Treated Conditions." Corrosion 41, no. 12 (December 1, 1985): 688–99. http://dx.doi.org/10.5006/1.3583005.

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Abstract The resistance of 300M steel to stress corrosion cracking in a 3.5% NaCl solution was studied as a function of heat treatment. Threshold stress intensity was affected by microstructural features, including prior austenite grain size, amounts of retained austenite, and twins, in addition to grain boundary segregation and fracture toughness of the steel. Crack growth rate was also dependent on microstructure and segregation, but the number of constraint points exerted the maximum influence. The effect of a modified heat treatment, which has been shown to improve all investigated mechanical properties to a significant extent, upon stress corrosion cracking (SCC) properties, was also studied. This heat treatment resulted in significantly higher threshold stress intensity and lower crack growth rate. The results are discussed in terms of microstructure and fractography.

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Xia, Yu, Juntao Lin, Zongwu Chen, Jun Cai, Jinxiang Hong, and Xiaobin Zhu. "Fatigue Cracking Evolution and Model of Cold Recycled Asphalt Mixtures during Different Curing Times." Materials 15, no. 13 (June 24, 2022): 4476. http://dx.doi.org/10.3390/ma15134476.

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This paper aims to investigate the fatigue cracking evolution of cold recycled asphalt mixtures with asphalt emulsion (CRME) under different curing times. The fatigue cracking model of CRME based on damage mechanics and fracture mechanics was analyzed according to the fatigue loading curve. Firstly, the fatigue cracking evolution of CRME was studied through an SCB strength test and SCB fatigue test. Then, the fatigue damage mechanics were used to establish a nonlinear fatigue cracking model, and the damage degree of CRME at the initial cracking point was determined. The Paris formula was used to characterize the law of fatigue crack propagation. Finally, the microstructure of CRME was observed by scanning electron microscopy (SEM) with the backscattering method. The results indicate that the initial cracking point appears at around 60% of the fatigue life according to the SCB fatigue test by means of image analysis. The damage variable was obtained through the cracking model, and the value of the damage variable was determined as 0.06–0.17 at the initial cracking point. In addition, the Paris formula showed that the crack growth of CRME can be reflected by the stress intensity factor and correlative parameters. Moreover, cement hydration products were mixed with the asphalt membrane to form a denser spatial structure during the curing process, which may provide higher fatigue performance of CRME. This research may provide a theoretical reference for studying the fatigue cracking behavior of CRME.

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Fischer, Gerhard, Helber Enrique Balaguera-López, and Javier Álvarez-Herrera. "Causes of fruit cracking in the era of climate change. A review." Agronomía Colombiana 39, no. 2 (May 1, 2021): 196–207. http://dx.doi.org/10.15446/agron.colomb.v39n2.97071.

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The objective of this review was to report on advances in environmental, cultural, and physiological aspects of fleshy fruit cracking to reduce or avoid this disorder, which affects many fruit species. Cracking is a physiological disorder that limits the production and quality of fleshy fruits because it affects the exocarp and mesocarp, especially with climate change and variability. Fruit cracking is generated by external factors (agronomic and environmental) and internal factors, several of which require exhaustive study. The incidence of cracking varies widely according to climatic characteristics during fruit development, different fruit species and varieties, growth sites, and crop management. This physiological disorder is aggravated by increases in rain intensity, especially after a dry season or in areas with increased temperatures. Knowledge on causes of cracking has generated management strategies that involve genetic improvement, ecophysiological conditions, agronomic practices such as pruning, irrigation, and fertilization (mainly with Ca, Mg, B, and K), applications of plant growth regulators, and use of plastic covers, etc. For several fruit trees, these strategies are effective, but in species such as the cape gooseberry, cracking remains without a full explanation or effective management.

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Goldsmith, C. C., S. M. Kamath, and A. H. Kumar. "Thin Film Critical Residual Stress for Metal Pads on a Ceramic Substrate." Advances in X-ray Analysis 36 (1992): 213–20. http://dx.doi.org/10.1154/s0376030800018814.

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AbstractResidual stresses present in thin films evaporated on ceramic substrates, can lead to loss of adhesion of the metal features to the ceramic, or, between metal films in multi-level stacks. If the adhesion is good, ceramic cracking may occur around the metal features. Long term one must avoid stress corrosion cracking in the ceramic. These residual stresses are generated by a variety of causes. In general, defect incorporation during the deposition process and thermal expansion mismatch between thin film and substrate play major roles.In this paper, we describe a method for determining the residual stresses that may be detrimental, or more accurately, the residual stress induced load that may cause reliability problems. This method involves evaporating metal pads or various thicknesses onto the ceramic to the point of failure, and measuring the residual stress loading on the substrate. A direct measure of this loading is the stress intensity factor which takes into account both the residual stress and pad or film thickness. Thus, a critical “load” or stress intensity at which substrate cracking or thin film delamination occurs can be estimated. This approach can be used to select the optimum metal-thickness combination for various substrates.

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Farid Uddin, A. K. M., M. Ohtsu, K. M. A. Hossain, and M. Lachemi. "Simulation of reinforcement-corrosion-induced crack propagation in concrete by acoustic emission technique and boundary element method analysis." Canadian Journal of Civil Engineering 34, no. 10 (October 1, 2007): 1197–207. http://dx.doi.org/10.1139/l07-028.

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Corrosion of reinforcement is one of the major causes of deterioration in reinforced concrete structures. Various crack patterns are nucleated around reinforcement in concrete due to expansion of corrosion products. Crack kinematics of locations, types, and orientations are quantitatively determined by the acoustic emission (AE) – simplified Green’s functions for moment tensor analysis (SiGMA) procedure in association with laboratory tests conducted on concrete specimens simulating corrosion-induced damage. These kinematic outcomes are obtained as three-dimensional (3-D) locations and vectors, and are thus visualized in 3-D by using virtual reality modeling language (VRML). Numerical analysis is conducted by the boundary element method (BEM) based on the concept of linear elastic fracture mechanics (LEFM) to clarify the mechanisms of corrosion-induced crack extension. Relationships between dimensionless stress intensity factors and cracking types are studied by BEM. Contributions of mode I and mode II failures are dependent on the cracking types. It is found that the process of crack propagation due to corrosion of reinforcement in concrete is mostly a mode I fracture with mixed-mode and, in a few cases, mode II fracture.Key words: acoustic emission, moment tensor, corrosion cracking, stress intensity factor.

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GAO, H., W. Cao, C. Fang, and E. R. de los Rios. "CORRELATION BETWEEN HYDROGEN INDUCED CRACKING INITIATION SITES AND CRITICAL STRESS INTENSITY FACTORS." Fatigue & Fracture of Engineering Materials and Structures 17, no. 9 (September 1994): 1069–74. http://dx.doi.org/10.1111/j.1460-2695.1994.tb00835.x.

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Kudra, T., I. Niewczas, B. Szot, and G. S. V. Raghavan. "Stress Cracking During High-Intensity Drying and its Effect on Grain Quality." Drying Technology 14, no. 2 (January 1996): 367–80. http://dx.doi.org/10.1080/07373939608917102.

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Oliveira, Elisangela do Prado, Karoline Soecki, Vitor Pereira Faro, and Alessander Christopher Morales Kormann. "Soil cracking propagation due to dryness and its relation to suction." MATEC Web of Conferences 337 (2021): 01021. http://dx.doi.org/10.1051/matecconf/202133701021.

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Investigation of Crack Intensity Factor is essential as it affects the mechanical and hydraulic behaviour of soils. Soil water coming from the wet seasons or from the water table, is removed by evaporation during the driest season. The loss of water provokes a significant increase in suction. When it exceeds the tensile strength of the soil, cracks occur that can modify the mechanical and mainly hydraulic properties of the soil, creating preferred paths for water infiltration. Little research is conducted on quantifying cracking in soil relating it to its hydraulic properties. This research aims to investigate the cracking of soils with focus on analysing its relation to water content and soil suction. Soils from a specific region in Brazil with clay predominance are collected and characterized. Unsaturated soil specimens are prepared and subjected to environmental real conditions in order to progressively check the consequences caused by the environment in soils with different clay content during four weeks. The Crack Intensity Factor is measured along the time through image processing. The water content is monitored through volume water content sensors. The measured results are evaluated to correlate crack intensity factor as function of weather variables and soil water content.

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Burnett, Timothy L., N. J. Henry Holroyd, Geoffrey M. Scamans, Xiaorong Zhou, George E. Thompson, and Philip J. Withers. "The role of crack branching in stress corrosion cracking of aluminium alloys." Corrosion Reviews 33, no. 6 (November 1, 2015): 443–54. http://dx.doi.org/10.1515/corrrev-2015-0050.

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AbstractStress corrosion cracks of all types are characterised by extensive crack branching, and this is frequently used as the key failure analysis characteristic to identify this type of cracking. For aluminium alloys, stress corrosion cracking (SCC) is almost exclusively an intergranular failure mechanism. For plate and extruded components, this had led to the development of test procedures using double cantilever beam and compact tension precracked specimens that rely on the pancake grain shape to constrain cracking, so that fracture mechanics can be applied to the analysis of stress intensity and crack velocity and the evolution of a characteristic performance curve. We have used X-ray computed tomography to examine in detail SCC in aluminium alloys in three dimensions for the first time. We have found that crack branching limits the stress intensity at the crack tip as the applied stress is shared amongst a number of cracks that are held together by uncracked ligaments. We propose that the plateau region observed in the v-K curve is an artefact due to crack branching, and at the crack tips of the many crack branches, cracking essentially occurs at constant K almost irrespective of the crack length. We have amplified the crack branching effect by examining a sample where the long axis of the pancake grains was inclined to the applied stressing direction. Our results have profound implications for the future use of precracked specimens for SCC susceptibility testing and the interpretation of results from these tests.

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Yan, Nu, I. Lee, Riichi Murakami, Daisuke Yonekura, J. Sun, and Satoshi Fukui. "Influence of Plasma Radical Nitriding on Fatigue Properties of SCM435 Steel." Key Engineering Materials 353-358 (September 2007): 266–69. http://dx.doi.org/10.4028/www.scientific.net/kem.353-358.266.

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The effect of plasma radical nitriding treatment on fatigue properties of SCM435 steel in super long life region was investigated. Fatigue tests were carried out using a dual-spindle rotating bending fatigue-testing machine at room temperature in air for the specimens nitrided at 773 K and 823 K for 3 hrs. The fatigue strength of nitrided specimen was greater than that of un-nitrided specimen and the crack initiation mode changed from the surface cracking of un-nitrided specimen to the subsurface cracking of nitrided specimen. Hardening layer and compressive residual stress were formed by nitriding, which resulted in the improvement of the fatigue strength. The stress intensity factor was calculated using facet area in Fish-eye fracture mode. As a result, the stress intensity factor indicated almost constant value, ~ 3-4 MPa·m1/2, regardless of the number of cycles to failure.

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Anam, Khairul, Chih Kuang Lin, and Anindito Purnowidodo. "Simulation of Cracking Behavior in Planar Solid Oxide Fuel Cell during Thermal Cycling." Key Engineering Materials 656-657 (July 2015): 484–89. http://dx.doi.org/10.4028/www.scientific.net/kem.656-657.484.

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Cracking behavior of positive electrode-electrolyte-negative electrode (PEN) assembly in a planar solid oxide fuel cells (pSOFC) during thermal cycling are investigated by using a commercial finite element analysis (FEA). The stress intensity factor for various combinations of surface crack size of 1 μm, 10 μm, and 100 μm and shape of semi-circular and semi-elliptical at highly stressed regions in the PEN are repeatedly calculated at room temperature and steady stage for twenty cycles. Simulation results indicate the stress intensity factor is significantly decreased at room temperature and is slightly increased at steady stage with increasing number of cycle. However, all the calculated stress intensity factors during thermal cycling in the present investigation are less than the corresponding fracture toughness given in the literature.

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Traidia, Abderrazak, Elias Chatzidouros, and Mustapha Jouiad. "Review of hydrogen-assisted cracking models for application to service lifetime prediction and challenges in the oil and gas industry." Corrosion Reviews 36, no. 4 (July 26, 2018): 323–47. http://dx.doi.org/10.1515/corrrev-2017-0079.

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AbstractThe present manuscript reviews state-of-the art models of hydrogen-assisted cracking (HAC) with potential for application to remaining life prediction of oil and gas components susceptible to various forms of hydrogen embrittlement (HE), namely, hydrogen-induced cracking (HIC), sulfide stress cracking (SSC), and HE-controlled stress corrosion cracking (SCC). Existing continuum models are compared in terms of their ability to predict the threshold stress intensity factor and crack growth rate accounting for the complex couplings between hydrogen transport and accumulation at the fracture process zone, local embrittlement, and subsequent fracture. Emerging multiscale approaches are also discussed, and studies relative to HE in metals and especially steels are presented. Finally, the challenges that hinder the application of existing models to component integrity assessment and remaining life prediction are discussed with respect to identification of model parameters and limitations of the fracture similitude, which paves the way to new directions for further research.

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Yang, Shang Yang. "Finite Element Transient Analysis on the Highway Reflective Crack in Temperature Change." Advanced Materials Research 594-597 (November 2012): 1482–85. http://dx.doi.org/10.4028/www.scientific.net/amr.594-597.1482.

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Temperature change of the semi-rigid base course is one of the reasons of the appearance of the reflective crack. The stress intensity factor of the semi-rigid asphalt pavement is calculated with the finite element method. Sensibility analysis is made on the parameters (modulus, thermal expansion coefficient, thickness) affecting the magnitude of the stress intensity factor. Above all, it is concluded that the graded gravel can reduce the reflective cracking

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Abouhussien, Ahmed A., and Assem AA Hassan. "Acoustic emission monitoring for bond integrity evaluation of reinforced concrete under pull-out tests." Advances in Structural Engineering 20, no. 9 (November 21, 2016): 1390–405. http://dx.doi.org/10.1177/1369433216678864.

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This article presents the results of an experimental investigation on the application of acoustic emission technique for monitoring the steel-to-concrete bond integrity of reinforced concrete structures. A series of direct pull-out tests were performed on 54 reinforced concrete unconfined prism samples with variable rebar diameter (10, 20, and 35 mm), embedded length (50, 100, and 200 mm), and concrete cover (20, 30, and 40 mm). The samples were tested under incrementally increasing monotonic loading while being continuously monitored via attached acoustic emission sensors. These sensors were utilized to acquire different acoustic emission signal parameters emitted throughout the tests until failure. Also, an acoustic emission intensity analysis was implemented on acoustic emission signal strength data to quantify the damage resulting from loss of bond in all tested specimens. This analysis employed the signal strength of all recorded acoustic emission hits to develop two additional parameters: historic index ( H ( t)) and severity ( Sr). The results of bond behavior, mode of failure, and free end slip were compared with the recorded acoustic emission data. The results showed that the cumulative number of hits, cumulative signal strength, H ( t), and Sr had a good correlation with different stages of bond damage from de-bonding/micro-cracking until bond splitting failure and bar slippage, which caused cover cracking or delamination. The analysis of cumulative signal strength and H ( t) curves enabled early identification of two progressive stages of bond degradation (micro-cracking and macro-cracking) and recognized the various modes of failure of the tested specimens. The variations of bar diameter, concrete cover, and embedded length yielded significant impacts on both the bond behavior and acoustic emission activities. The results also presented developed intensity classification charts, based on H ( t) and Sr, to assess the bond integrity and to quantify the bond deterioration (micro-cracking, macro-cracking, and rebar slip) in reinforced concrete structures.

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Zhao, Guifeng, Lei Zhang, Bing Dai, Yong Liu, Zhijun Zhang, and Xinyao Luo. "Experimental Investigation of Pre-Flawed Rocks under Dynamic Loading: Insights from Fracturing Characteristics and Energy Evolution." Materials 15, no. 24 (December 13, 2022): 8920. http://dx.doi.org/10.3390/ma15248920.

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Different fractures exist widely in rock mass and play a significant role in their deformation and strength properties. Crack rocks are often subjected to dynamic disturbances, which exist in many fields of geotechnical engineering practices. In this study, dynamic compression tests were carried out on rock specimens with parallel cracks using a split hopkinson pressure bar apparatus. Tests determined the effects of strain rate and crack intensity on dynamic responses, including progressive failure behavior, rock fragmentation characteristics, and energy dissipation. Based on the crack classification method, tensile–shear mixed cracking dominates the failure of rock specimens under the action of impact loading. Increasing the flaw inclination angle from 0°–90° changes the predominant cracking mechanism from tensile cracking to mixed tensile–shear cracking. The larger the loading rate, the more obvious the cracking mechanism, which indicates that the loading rate can promote the cracking failure of rock specimens. The fragmentation analysis shows that rock samples are significantly broken at higher loading rates, and higher loading rates lead to smaller average fragment sizes; therefore, the larger the fractal dimension is, the more uniform the broken fragments of smaller sizes are. Energy utilization efficiency decreases while energy dissipation density increases with increasing strain rate. For a given loading rate, the energy absorption density and energy utilization efficiency first decrease and then increase with increasing flaw inclination, while the rockburst tendency of rock decreases initially and then increases. We also find that the elastic–plastic strain energy density increases linearly with the total input energy density, confirming that the linear energy property of granite has not been altered by the loading rate. According to this inherent property, the peak elastic strain energy of the crack specimen can be calculated accurately. On this basis, the rockburst proneness of granite can be determined quantitatively using the residual elastic energy index, and the result is consistent with the intensity of actual rockburst for the specimens.

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Hrairi, Meftah, Arafath Ali, and Abd El Fattah Rizk. "Analysis of Thermal Stress Intensity Factors for Edge Cracked Bimaterial System." Advanced Materials Research 576 (October 2012): 766–69. http://dx.doi.org/10.4028/www.scientific.net/amr.576.766.

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The thermo elastic edge-cracking problem in bimaterial systems subjected to convective heating is considered. The medium is assumed to be insulated on one surface and exposed to sudden convective heating on another surface containing the edge crack. Superposition and uncoupled quasi-static thermoelasticity principles are adopted to formulate the problem. Thermal stress distribution and stress intensity factor values had been determined using the finite element software ANSYS for two different bi-material systems containing edge crack normal to the interface.

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Peet, M. M. "Fruit Cracking in Tomato." HortTechnology 2, no. 2 (April 1992): 216–23. http://dx.doi.org/10.21273/horttech.2.2.216.

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The environmental and physiological causes of cracking or splitting of soft fruits and citrus as they ripen are not well understood. This paper explores factors contributing to radial cracking in tomatoes, gives suggestions for prevention of cracking, and suggests directions for future research. Fruit cracking occurs when there is a rapid net influx of water and solutes into the fruit at the same time that ripening or other factors reduce the strength and elasticity of the tomato skin. In the field, high soil moisture tensions suddenly lowered by irrigation or rains are the most frequent cause of fruit cracking. Low soil moisture tensions reduce the tensile strength of the skin and increase root pressure. In addition, during rain or overhead irrigation, water penetrates into the fruit through minute cracks or through the corky tissue around the stem scar. Increases in fruit temperature raise gas and hydrostatic pressures of the pulp on the skin, resulting in immediate cracking in ripe fruit or delayed cracking in green fruit. The delayed cracking occurs later in the ripening process when minute cracks expand to become visible. High light intensity may have a role in increasing cracking apart from its association with high temperatures. Under high light conditions, fruit soluble solids and fruit growth rates are higher. Both of these factors are sometimes associated with increased cracking. Anatomical characteristics of crack-susceptible cultivars are: 1) large fruit size, 2) low skin tensile strength and/or low skin extensibility at the turning to the pink stage of ripeness, 3) thin skin, 4) thin pericarp, 5) shallow cutin penetration, 6) few fruits per plant, and 7) fruit not shaded by foliage. Following cultural practices that result in uniform and relatively slow fruit growth offers some protection against fruit cracking. These practices include maintenance of constant soil moisture and good Ca nutrition, along with keeping irrigation on the low side. Cultural practices that reduce diurnal fruit temperature changes also may reduce cracking. In the field, these practices include maintaining vegetative cover. Greenhouse growers should maintain minimal day/night temperature differences and increase temperatures gradually from nighttime to daytime levels. For both field and greenhouse tomato growers, harvesting before the pink stage of ripeness and selection of crack-resistant cultivars probably offers the best protection against cracking. Areas for future research include developing environmental models to predict cracking and exploring the use of Ca and gibberellic acid (GA) sprays to prevent cracking.

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Korte, Sara, Veerle Boel, Wouter de Corte, and Geert de Schutter. "Fracture Toughness and Cracking Behaviour of SCC Compared to VC." Key Engineering Materials 577-578 (September 2013): 205–8. http://dx.doi.org/10.4028/www.scientific.net/kem.577-578.205.

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Vibrated concrete (VC) and self-compacting concrete (SCC) have a substantially different composition, resulting in dissimilar mechanical properties regarding cracking behaviour. The critical value of the mode I stress-intensity factor KICis an appropriate fracture parameter for evaluating fracture toughness and can be obtained from three-point bending tests (3PBT) on small, notched specimens. Subsequent determination of the energy release rate thus allows to examine the crack propagation and fracture process of both concrete types. This paper describes the results of such 3PBTs on samples, made from VC and SCC. Evaluation of the cracking behaviour, derived from these results, reveals remarkable differences.

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Yan, Xi Kang, Zhan Wei Li, Pei Chen, and Jun E. Liu. "Mechanical Analysis on Reinforced Concrete Beams under Salt Fog Corrosion Test." Applied Mechanics and Materials 94-96 (September 2011): 225–29. http://dx.doi.org/10.4028/www.scientific.net/amm.94-96.225.

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In the background of buildings in coastal area being corroded by salt fog, this paper studies 12 beams of different intensity and protective layers to simulate the real effect of the corrosion for 20 years. Elaborates the phenomenon of enhancement of the concrete compressive strength and the bearing capacity and cracking load of test beams, and makes an indepth analysis on the mechanism of this phenomenon, at the same time the concept of the additional expansion prestress is introduced; a mathematical model of the additional expansion prestress is establish and the computational model of the cracking load is derived.

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Dobránszky, János, Attila Magasdi, and János Ginsztler. "Investigation of Notch Sensitivity and Blade Breakage of Bandsaw Blade Steels." Materials Science Forum 473-474 (January 2005): 79–84. http://dx.doi.org/10.4028/www.scientific.net/msf.473-474.79.

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Bandsaw blades are one of the most commonly used tools of the wood cutting industry. Their base materials are mostly unalloyed or poorly Cr-alloyed tool steels. After the review of the bandsaw blade’s cyclic load characteristics, we present the typical failures, which can be, originate in it’s cracking. With the use of these information an overall systematization has been set up by the bandsaw blade cracking types and its root causes. The main place of the failure is the weld and the heat-affected zone’s area where the welding can failure or the lack of toughness can produce cracking. An other zone, where cracking may appear is the bandsaw blade’s tooth gullet because it raises the stress intensity factor. Special material testing methods have been made to investigate the tooth gullet’s notch sensitivity from the test results that a comparison of several bandsaw blade base material, are reviewed. With the use of the results a notch sensitivity rating system has been worked out, which can be used to rate different bandsaw blade base material’s notch sensitivity.

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Gu, Kyoung Hee, Ki Sik Lee, Gum Hwa Lee, and Ki Woo Nam. "Evaluation of Fatigue Life of Ultra-High-Strength Steel under Stress Corrosion Environment." Applied Mechanics and Materials 907 (June 22, 2022): 1–7. http://dx.doi.org/10.4028/p-s303xf.

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Ultra-high-strength steel (UHSS) structures are exposed to corrosive environments during service, and hydrogen-assisted cracking (HAC) may occur owing to stress corrosion cracking and hydrogen embrittlement. In this study, the HAC threshold stress intensity factor and fatigue life of UHSS steel were evaluated by applying stress in a corrosive environment to prevent structural fracture. For specimen with semicircular slits by electric discharge machining, fatigue limit was obtained by static fatigue test under corrosive environment. The fatigue limit of the crack specimen was evaluated by the fatigue limit of the experiment and HAC threshold stress intensity factor, and comparative evaluation was performed. On the surface of cracks, grain boundaries were embrittled by corrosion, and grains were clearly observed. Meanwhile, cracks in the surface direction propagated slightly, unlike cracks in the depth direction. The static fatigue limit of UHSS (SKD11:HV670) was determined to be 400 MPa, and the fatigue limit of the crack specimen could be evaluated. The experimental results agreed well with the evaluation results.

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Li, Siqi, Yong-Sheng Chen, and Hong-Bo Liu. "EXAMINED AND ANALYSIS OF EMPIRICAL SEISMIC DAMAGE OF WORKSHOP BUILDING." Stavební obzor - Civil Engineering Journal 31, no. 1 (April 30, 2022): 169–80. http://dx.doi.org/10.14311/cej.2022.01.0013.

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To deeply explore the typical damage characteristics and vulnerability characteristics of workshop building (WB) in actual earthquakes, the empirical field reconnaissance and observation of the WB damaged to varying degrees in the Mw 8.0 earthquake in Wenchuan County, Sichuan Province, China on May 12, 2008 were conducted. The investigation results indicated that the typical seismic damage forms of industrial buildings in multiple intensity regions were: local and overall collapse, column cracking and crane beam displacement, collapse and cracking of wall, and damage of supporting and connecting members, the field investigation pictures of typical seismic damage were provided, respectively. According to different typical failure characteristics, the seismic damage mechanism and seismic capacity were analyzed, and the measures and suggestions to improve the seismic capacity of industrial buildings with different material categories were conducted. The conclusions can provide necessary reference for the revision of the seismic code of industrial plants and the seismic intensity scale of China.

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Jokūbaitis, Vidmantas, and Petras Pukelis. "INFLUENCE OF LONGITUDINAL REINFORCEMENT ON DEVELOPMENT OF NORMAL CRACKS." JOURNAL OF CIVIL ENGINEERING AND MANAGEMENT 11, no. 1 (March 31, 2005): 33–37. http://dx.doi.org/10.3846/13923730.2005.9636330.

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Using a model of normal crack propagation in reinforced concrete members, an analytical expression is presented for the stress intensity factor defining the intensity of stress in area at the crack tip. This factor is in linear relationship to the stress in tensile reinforcement, which can be determined by different methods. The analysis performed indicates that there is a direct relationship between the stress intensity factor and normal crack depth, when a stable and chaotic propagation of cracks in the initial cracking stage of the member terminates. In addition, expression of this relationship depends significantly on reinforcement ratio of underreinforced beams.

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Zhou, Tai Quan, Tommy Hung Tin Chan, and Yuan Hua. "Fatigue Damage Analysis on Crack Growth and Fatigue Life of Welded Bridge Members with Initial Crack." Key Engineering Materials 324-325 (November 2006): 251–54. http://dx.doi.org/10.4028/www.scientific.net/kem.324-325.251.

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The behavior of crack growth with a view to fatigue damage accumulation on the tip of cracks is discussed. Fatigue life of welded components with initial crack in bridges under traffic loading is investigated. The study is presented in two parts. Firstly, a new model of fatigue crack growth for welded bridge member under traffic loading is presented. And the calculate method of the stress intensity factor necessary for evaluation of the fatigue life of welded bridge members with cracks is discussed. Based on the concept of continuum damage accumulated on the tip of fatigue cracks, the fatigue damage law suitable for steel bridge member under traffic loading is modified to consider the crack growth. The proposed fatigue crack growth can describe the relationship between the cracking count rate and the effective stress intensity factor. The proposed fatigue crack growth model is then applied to calculate the crack growth and the fatigue life of two types of welded components with fatigue experimental results. The stress intensity factors are modified by the factor of geometric shape for the welded components in order to reflect the influence of the welding type and geometry on the stress intensity factor. The calculated and measured fatigue lives are generally in good agreement, at some of the initial conditions of cracking, for a welded component widely used in steel bridges.

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Akhi, Atika Hossain, and Ashutosh Sutra Dhar. "Stress intensity factors for external corrosions and cracking of buried cast iron pipes." Engineering Fracture Mechanics 250 (June 2021): 107778. http://dx.doi.org/10.1016/j.engfracmech.2021.107778.

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Hedia, Hassan S. M., and A. A. Fattah. "Effect of Notch Tip Sharpness and Pre-Cracking on the Stress Intensity Factor." Materials Testing 44, no. 4 (April 1, 2002): 122–25. http://dx.doi.org/10.1515/mt-2002-440405.

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Hedia, Hassan S. M., and Mohamed A. N. Shabara. "Effect of Notch Tip Sharpness and Pre-Cracking on the Stress Intensity Factor." Materials Testing 44, no. 4 (April 1, 2002): 117–21. http://dx.doi.org/10.1515/mt-2002-440404.

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Journal articles on the topic 'Cracking intensity'

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