Journal articles: 'Cement creep'

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Li, Yimin, Mulbah Yombah, Ahmed Abdulakeem Temitope, Xiaolong Zou, Fayong Yang, Wenbo Li, and Hongjun Jing. "Research on Creep Characteristics and Influencing Factors of Cement Asphalt Composite Binder." Mathematical Problems in Engineering 2020 (December 29, 2020): 1–13. http://dx.doi.org/10.1155/2020/6614920.

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Cement emulsified asphalt composite material (CA composite cement) has the excellent properties of cement and emulsified asphalt cement. As a composite cementing material, cement emulsified asphalt concrete can be one of the choices of road paving materials. However, under the effect of temperature and wheel load, the performance of it may get worse; especially, the creep behavior of CA composite cement has an important influence on the stability of pavement structure. This paper mainly focuses on the research on the creep and creep recovery performance of CA composite cement, determines the raw materials and proportions of CA composite cement, and formulates experimental research programs such as creep and creep recovery tests and stress scanning tests. The creep and creep recovery test research of CA composite cement was carried out, and the influence of creep and creep recovery characteristics, temperature, and A/C on the creep mechanical properties of CA composite cement was analyzed. The results show that the creep compliance of CA composite cement decreases with the increase of aging degree, the static mechanical properties tend to be elastic as a whole, and different factors such as temperature and A/C have different effects on the viscoelastic-plastic mechanical properties of the material.

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Nesvetaev, G. V., I. V. Korchagin, and Y. Y. Lopatina. "On Effect of Superplasticizers and Mineral Additives on Creep Factor of Hardened Cement Paste and Concrete." Solid State Phenomena 265 (September 2017): 109–13. http://dx.doi.org/10.4028/www.scientific.net/ssp.265.109.

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The relationship between the creep factor of concrete and hardened cement paste and the E-modulus of aggregate and evaluation of the effects of some modifiers on the creep factor of the hardened cement paste was determined. The influence of the SP on the creep factor of hardened cement paste is ambiguous: SP may increase, decrease, or not change the creep factor. The possible deviation of creep factor of hardened cement paste with the SP in certain cases can be up to 4 times. The average statistical increase in the creep factor of hardened cement paste may be 7 to 35%. The creep factor of regular concrete is equal 0.43 - 0.9 value of the creep factor of hardened cement paste. Superplasticizers may increase the creep of concrete up to 30% and in some cases - up to 3 times. Silica fume, metakaolin, white ash, including when used with the superplasticizers, may reduce the creep of concrete from 15 to 50%. An equation was suggested to calculate the E-modulus of concrete with the volume of hardened cement paste of 0.27 - 0.35 as a function of E-modulus of hardened cement paste and E-modulus of the aggregates.

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Padevět, Pavel, and Petr Bittnar. "Creep of Cement Pastes with Content of Fly Ash one Year Old." Applied Mechanics and Materials 732 (February 2015): 385–88. http://dx.doi.org/10.4028/www.scientific.net/amm.732.385.

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The paper discusses the creep cement pastes with addition of fly ash. The evolution of the creep was observed in age of one year, for length one month. The size of the creep is influenced by the amount the creep physically bound water. The material properties depend on the ratio of components from which the cement paste is composed. The paper presents the results of creep measurement for the ratio of cement and fly ash 70:30, 60:40 and 50:50. The basic creep and creep of the saturated cement paste were calculated from measurements.

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Padevět, Pavel, and Petr Bittnar. "Creep of the Four Month Old Cement Paste with Content of Fly Ash." Applied Mechanics and Materials 827 (February 2016): 251–54. http://dx.doi.org/10.4028/www.scientific.net/amm.827.251.

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The paper presents research in area of the measurement of cement paste creep. The propertiesof four month cement paste mixed with fly ash are presented. The creep and shrinkage are measuredinto the lever mechanism. The basic creep and creep of the saturated cement paste are calculatedfrom data of measurement. Finally, creep of four months old specimens is discussed.

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Norman, T. L., V. C. Saligrama, K. T. Hustosky, T. A. Gruen, and J. D. Blaha. "Axisymmetric Finite Element Analysis of a Debonded Total Hip Stem With an Unsupported Distal Tip." Journal of Biomechanical Engineering 118, no. 3 (August 1, 1996): 399–404. http://dx.doi.org/10.1115/1.2796023.

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A tapered femoral total hip stem with a debonded stem-cement interface and an unsupported distal tip subjected to constant axial load was evaluated using two-dimensional (2D) axisymmetric finite element analysis. The analysis was performed to test if the mechanical condition suggest that a “taper-lock” with a debonded viscoelastic bone cement might be an alternative approach to cement fixation of stem type cemented hip prosthesis. Effect of stem-cement interface conditions (bonded, debonded with and without friction) and viscoelastic response (creep and relaxation) of acrylic bone cement on cement mantle stresses and axial displacement of the stem was also investigated. Stem debonding with friction increased maximum cement von Mises stress by approximately 50 percent when compared to the bonded stem. Of the stress components in the cement mantle, radial stresses were compressive and hoop stresses were tensile and were indicative of mechanical taper-lock. Cement mantle stress, creep and stress relaxation and stem displacement increased with increasing load level and with decreasing stem-cement interface friction. Stress relaxation occur predominately in tensile hoop stress and decreased from 1 to 46 percent over the conditions considered. Stem displacement due to cement mantle creep ranged from 614 μm to 1.3 μm in 24 hours depending upon interface conditions and load level.

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Padevět, Pavel, and Petr Bittnar. "The Cement Paste Creep with Addition of Fly Ash in Time and Ratio of Parts 60/40." Applied Mechanics and Materials 486 (December 2013): 341–46. http://dx.doi.org/10.4028/www.scientific.net/amm.486.341.

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The article solves the comparing of the resize of cement paste creep with addition of fly ash in time. Creep was observed in the one monthly measurement for 4 and 10 months. The cement paste was prepared with fly ash in the ratio of the components 60/40 in favor of the cement components. Development of basic creep and creep was observed in water-saturated material. The measurement results are used as input data for the simulation of creep by the mathematical model and determine the values of the creep coefficient of cement paste. Results and comparison of q coefficients are presented.

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Wang, Xin Jie, and Ping Hua Zhu. "Effcets of Water-Cement Ratio on Tensile Basic Creep of Early-Aged Concrete." Advanced Materials Research 243-249 (May 2011): 5756–59. http://dx.doi.org/10.4028/www.scientific.net/amr.243-249.5756.

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The effects of water-cement ratio on the tensile creep of early-age concrete under constant load were investigated. Creep and shrinkage of concrete under sealed curing condition was researched to determine the tensile basic creep of concrete. The results indicate that, as in compression, creep of concrete in tensile is very sensitive to water to cement ratio. The results also indicate that the tensile creep increases with the water to cement ratio. And that the tensile creep develops rapidly within the first day after loading.

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Qin, Xiantao, Siyue Zhu, and Rong Luo. "Effect of Fiber Reinforcement on Creep and Recovery Behavior of Cement–Emulsified Asphalt Binder." Materials 15, no. 21 (October 24, 2022): 7451. http://dx.doi.org/10.3390/ma15217451.

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In order to evaluate and improve the deformation behavior of cement–emulsified asphalt binder (CA) in cement–emulsified asphalt mixture, this study investigated the reinforcement of small additions of fibers (2%, 4%, and 6% addition by mass of cement) on the deformation resistance of CA. A repeated creep recovery test was implemented that measures the recovery rate of creep deformation and accumulated strain. Further, an improved piecewise curve-fitting method was used to determine the parameters of Burgers model, then the creep compliances were fitted and calculated. The results show the repeated creep recovery test to be a suitable method for obtaining useful information about creep and recovery deformation of fiber-reinforced CA. The influence of fiber types and dosages on the deformation recovery ability is determined based on the creep recovery ratio and accumulated strain. The improved piecewise curve-fitting method has high accuracy. Thereafter, the reinforcement effect was analyzed through the evolution of creep compliance under loading. Therefore, this paper can provide a reference for enhancing the properties of cement–emulsified asphalt mixture by maximizing the fiber reinforcement.

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Tempest, Brett, Janos Gergely, and David C. Weggel. "ENGINEERING CHARACTERIZATION OF STRENGTH AND ELASTIC PROPERTIES OF GEOPOLYMER CEMENT CONCRETE MATERIALS." Journal of Green Building 10, no. 4 (November 2015): 87–106. http://dx.doi.org/10.3992/jgb.10.4.87.

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Geopolymer cements provide an alternative to the Portland cement used to produce structural concrete. In this study, geopolymer cements were used to create concrete having compressive strength in the range of 34 to 83 MPa (5,000–12,000 psi). The mechanical properties of these concrete materials were evaluated to determine the compressive and tensile strengths and immediate and long term elastic behaviors. The geopolymer cement concrete (GCC) was found to perform in a similar manner to Portland cement concrete (PCC). Long term shrinkage and creep properties of GCC materials were found to be lower than the values typical for PCC.

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Loamrat, Kraisit, Manote Sappakittipakorn, and Piti Sukontasukkul. "Electrical Resistivity of Cement-Based Sensors under a Sustained Load." Advanced Materials Research 931-932 (May 2014): 436–40. http://dx.doi.org/10.4028/www.scientific.net/amr.931-932.436.

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This research was to study the influence of a sustained load on the electrical resistivity of a cement-based sensor. The cement-based sensor in this study was made of cement paste having water to cement ratio of 0.4 with the addition of graphite powder at 2% and 4% by weight of cement and carbon fibers at 2% and 4% by volume. The sustained load was applied on the cement-based-sensor using a sustain machine to control a compressive force continually at 30% of its ultimate compressive strength for a period of 30 days. The test results showed that the sustained load induced a creep strain on the cement-based-sensor. The graphite incorporated cement-based sensor showed higher creep strain than the plain cement-based sensor while the carbon fiber cement-based sensor showed lesser. In addition, it was shown that the creep strains affect the electrical resistivity of the cement-based sensors.

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Sun, Fu Ting, Cheng Xue She, and Kun Li. "Research on Creep Property of Cement Grouted Joint." Advanced Materials Research 243-249 (May 2011): 2819–24. http://dx.doi.org/10.4028/www.scientific.net/amr.243-249.2819.

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The creep property of cement grouted joint is studied based on creep test and theoretical analysis. Firstly, the multi-stage shear creep test under constant normal stress, joint roughness and cement filled thickness is carried out to obtain the creep deformation. Then the conventional linear Nishihara model is used to fit the test results. Due to the big deviation of the theoretical results from the test, the instantaneous elastic shear stiffnesses under different loading stages are calculated. It is found that they vary with the shear stress. The reasons for the nonlinearity are analyzed. Finally the parameters of the Nishihara model are modified to be nonlinear and fit with the test results showing good coincidence between them. These researches release the creep property of the cement grouted joint, and will provide a good basis for further research considering more influencing factors such as normal stress, joint roughness and cement filled thickness.

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Gailitis, Rihards, Beata Figiela, Kalvis Abelkalns, Andina Sprince, Genadijs Sahmenko, Marta Choinska, and Martin Duarte Guigou. "Creep and Shrinkage Behaviour of Disintegrated and Non-Disintegrated Cement Mortar." Materials 14, no. 24 (December 7, 2021): 7510. http://dx.doi.org/10.3390/ma14247510.

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One way to prevent cement from ending up in landfills after its shelf life is to regain its activity and reuse it as a binder. As has been discovered, milling by planetary ball mill is not effective. Grinding by collision is considered a more efficient way to refine brittle material and, in the case of cement, to regain its activity. There has been considerable research regarding the partial replacement of cement using disintegrated cement in mortar or concrete in the past few decades. This article determines and compares the creep and shrinkage properties of cement mortar specimens made from old disintegrated, old non-disintegrated, and new non-disintegrated Portland cement. The tests show that the creep strains for old disintegrated and old non-disintegrated cement mortars are close, within a 2% margin of each other. However, the creep strains for new non-disintegrated cement mortar are 30% lower. Shrinkage for old disintegrated and non-disintegrated cement mortar is 20% lower than for new non-disintegrated cement mortar. The research shows that disintegration is a viable procedure to make old cement suitable for structural application from a long-term property standpoint. Additionally, it increases cement mortar compressive strength by 49% if the cement is disintegrated together with sand.

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Zacharda, Vojtěch, Petr Štemberk, and Jiří Němeček. "Nanomechanical Performance of Interfacial Transition Zone in Fiber Reinforced Cement Matrix." Key Engineering Materials 760 (January 2018): 251–56. http://dx.doi.org/10.4028/www.scientific.net/kem.760.251.

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This paper shows a micromechanical study of interfacial transition zone (ITZ) around steel fiber in cement paste. It investigates microstructure and mechanical performance of the ITZ by a combination of nanoindentation and scanning electron microscopy (SEM). The investigated specimens were made from cement CEM I 42.5R paste with dispersed reinforcement in the form of steel fiber TriTreg 50 mm. The SEM demonstrated larger porosity and smaller portion of clinkers in the ITZ. Nanoindentation delivered values of elastic modulus, hardness and creep parameters around the fiber. An average value of elastic modulus in ITZ was at the level of 67% in comparison with cement bulk and the width of ITZ was about 40 µm. The value of hardness was found to be 60% of the average hardness of the bulk cement paste. The measured load-displacement curves were used for calculation of creep indentation parameter (CIT) and the creep compliance function. An average value of the creep compliance in the ITZ was found to be two times higher than in the cement bulk.

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Padevět, Pavel, and Petr Bittnar. "The Creep of the Cement Mortar with Relation of Cement and Sand in Same Relation." Applied Mechanics and Materials 769 (June 2015): 285–88. http://dx.doi.org/10.4028/www.scientific.net/amm.769.285.

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The paper is focused on the measurement of creep and shrinkage and on the describing of measuring data reconstruction. The cement mortar was prepared from Portland cement and sand in relation 1:1. The cement mortar was tested in water saturated and dried conditions [1]. The tested specimens were four months old. The raw data were damaged by power outages. Evaluation of creep measurements of the reconstructed data was carried out and is presented.

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Padevět, Pavel, and Petr Bittnar. "Creep of Eight Years Old Cement Paste." Applied Mechanics and Materials 825 (February 2016): 41–44. http://dx.doi.org/10.4028/www.scientific.net/amm.825.41.

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The paper presents research of shrinkage of the cement paste. The tested specimens wereprepared eight years ago from Portland cement CEM II and water. The observation was focused onthe evolution of creep in long time and for very old material. The material properties like a compressionstrength and Modulus of elasticity were observed according with the creep.

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Hojati, Maryam, Farshad Rajabipour, and Aleksandra Radlińska. "Creep of alkali-activated cement mixtures." Case Studies in Construction Materials 16 (June 2022): e00954. http://dx.doi.org/10.1016/j.cscm.2022.e00954.

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Padevět, Pavel, and Petr Bittnar. "Creep of Cementitous Materials with Addition of Fly Ash in Time." Advanced Materials Research 742 (August 2013): 182–86. http://dx.doi.org/10.4028/www.scientific.net/amr.742.182.

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The cement paste forms the basis of a concrete composite. This article is focused on the analysis of the creep of cement paste with fly ash based on experimental measurements. Measurement results of creep-dried and water saturated pastes are presented. The ratio of cement to fly ash of 1:1 was used for the production of the mixture. Experimental measurements were carried out on material age of 4 months.

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Padevět, Pavel, and Petr Bittnar. "Comparison of Cement Pastes Creep with Admixtures of Fly Ash." Applied Mechanics and Materials 837 (June 2016): 34–37. http://dx.doi.org/10.4028/www.scientific.net/amm.837.34.

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The article is devoted to compare the size of the creep for a time period of cement pastes with admixture of different amounts of fly ash. Attention is given to the size of the deformations that occur in materials saturated with water and also in the dried matrices. The presented results comparing creep size for cement pastes containing fly ash 30 and 50 %. Influence of the amount of ash and the amount of water to the creep size is evaluated in the conclusion.

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Sprince, Andina, Tomass Kozlovskis, Rihards Gailitis, Juozas Valivonis, Kinga Korniejenko, and Arnaud Castel. "Tensile Creep of Cement and Concrete Composites: Monitoring by Means of 2D-Digital Image Correlation." Applied Sciences 11, no. 18 (September 8, 2021): 8334. http://dx.doi.org/10.3390/app11188334.

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Creep and shrinkage of Cement and Concrete Composites (CCC) are significant properties that need to be considered to use these materials in practice. Many previous scientific studies revealed CCC creep characteristics under sustained compression and shrinkage, using traditional test methods from design standards. Because of the complexity of experimental procedures, CCC creep in tension has not been studied as close. Furthermore, there is no unified standard that proposes applicable testing methods or specific testing apparatus. This study examines the suitability of 2D—Digital Image Correlation (DIC) to observe the creep deformations of specimens under tension. Ordinary Portland cement (OPC) mortar with 1% polyvinyl alcohol (PVA) fibres has been investigated in the research. Compact tension (CT) specimens 150 × 150 × 12 mm (with a notch) were used. Creep deformations under sustained uniaxial tension (applied loading corresponding to 60% of the ultimate strength) were measured. DIC images were captured using an entry/mid-level DSLR camera. Results show that DIC is suitable for studying uniaxial tensile creep of cement and concrete composites. Deformation of specimens in tension was similar to that measured using the conventional method (using surface-attached gauges).

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Yuan, Fang. "Mortar Thickness Calculation of Bonding Layer in Large-Scale Bridge Construction." Applied Mechanics and Materials 651-653 (September 2014): 1188–91. http://dx.doi.org/10.4028/www.scientific.net/amm.651-653.1188.

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The traditional calculation methods of mortar thickness without considering creep of the bridge caused by the mortar thickness, affects the safety and quality of the bridge. This paper proposes a mortar thickness calculation method of bonding layer in large-scale bridge construction based on Kalman filtering. The method uses the mortar creep impact indicators system, selects the creep test data as sample, and analyzes its sensitivity to the thickness to get the intensity of factors affecting mortar creep. It also filters the interface of amount of cement, aggregate content, water-cement ratio and components, and effectively computes the thickness which reduces the cost while improving the quality of bridge construction.

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Choi, Hyeonggil, and Bongsuk Cho. "Calculation of Constrained Stress in Expansive Mortar with a Composite Creep Model." Advances in Materials Science and Engineering 2016 (2016): 1–10. http://dx.doi.org/10.1155/2016/2372835.

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The creep phenomenon of hardening cement paste mixed with an expansive additive was modeled by considering the creep performance of hydration products of cement and expansive additive. A new composite model that is appropriate for particle conditions is proposed by considering the balance of the hydration products of cement and expansive additive and the stress redistribution phenomenon of hydration products newly generated by the progress of hydration. The creep of mortar and concrete mixed with the expansive additive was evaluated using a composite model of the paste and aggregate. Under the assumption that the modeled creep deformation is proportional to the stress and the gel volume of the hydration products, which allows the law of superposition to be applied, the distribution stress was predicted by applying the step-by-step method at each time increment. By predicting the maximum tensile stress applied to an inner steel ring through a creep analysis based on the measured deformation of the inner steel ring, it is possible to predict the stress progression with age to some degree.

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Balevičius, Robertas, and Eugenijus Dulinskas. "DETERMINATION OF UNIT CHARACTERISTICS OF CONCRETE LINEAR CREEP/BETONO TIESINIO VALKŠNUMO VIENETINIŲ RODIKLIŲ NUSTATYMAS." JOURNAL OF CIVIL ENGINEERING AND MANAGEMENT 6, no. 2 (April 30, 2000): 87–96. http://dx.doi.org/10.3846/13921525.2000.10531571.

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t is very important to take into account time-dependent non-elastic deformations and variation of concrete mechanical characteristics in analysis of concrete structures. In codes of many countries, such as ENV 1992-1-1 (Eurocode) [1], ACI 209–92 (USA), AS 3600–1988 (Australia), DIN 4227 (Germany) and others, variation of creep deformations and physical mechanical characteristics with time is specified. The Code acting in Lithuania SNiT (Russ. СНиП 2.03.01-84*) [2] does not describe these characteristics directly. Calculation of time-dependent processes in the code acting in Lithuania SNiT [2] is associated with specific creep characteristics (specific creep, coefficient of creep) and with regulation of creep deformations. Such integral characteristics as steel prestress losses due to concrete creep associated with these specific characteristics are determined by empirical formulas which are obtained by tests with verification of stress and strain state of individual members. There are many investigations for determination of concrete creep characteristics. In the investigation [3], different relationships for determining specific characteristics of „young” and „old” concrete are proposed to apply, in recommendations [4] characteristics are presented according to their authors only for design, relationships presented in monograph [5] describe very well the creep of „young” concrete, code [6] regulates only limit values of creep characteristics. Characteristics determined by Eurocode [1] depend on the main factors influencing creep deformations but their relationship with regulations of the code [2] used in Lithuania is not clear. Therefore in this investigation relationships of specific creep characteristics for various compression grades of normal weight concrete describing great area of long-term deformations and taking into account the main factors influencing concrete creep were proposed. The proposed relationships also comply with regulation area of the code [2]. Analysis of specific concrete creep deformations based on steel prestress loss due to concrete creep calculation method [2] is presented in Chapter 2. Relationships for pure concrete specific creep (20–21) and for creep coefficient (23) were obtained. Comparison of these expressions with specific creep calculated according to code EC-2 [1] and recommended in [4] methods is shown in Figs 1–2. In Chapter 3, mathematical description of pure specific concrete creep (21) and of pure creep coefficient (23) based on theory of elastic plastic body is presented. Comparison of specific concrete creep characteristics determined by (35) and (37) relationships with analogous characteristics applied in codes [1, 4] is shown in Figs 3–4. In Chapter 4–5, coefficients (40), (41) evaluating the influence of water-cement ratio and quantity of cement paste on concrete creep deformations are presented. Analysis of experimental results of investigations of specific creep characteristics shows that time-dependent deformation properties depend not only on factors by which concrete creep is specified in codes and discussed in Chapters 3–4, but also on quantity of cement paste and water-cement ratio. Conformity of specific creep values determined by relationships (35) proposed by us taking into account coefficients (40–41) with standard concrete [3] and experimental creep investigation results [18] are shown in Figs 4–5. Statistical analysis of experimental and theoretical concrete creep deformation values determined according to the method proposed by us and by the code [1] is presented in Table 2. Mean ratios κ = C eksp (t, t 0)/C(t, t 0), mean square deviations σκ and coefficient of variation δκ were calculated. It was determined that theoretical values of specific creep calculated by the proposed method comply better (coefficient of variation δκ=27.7%) with presented test results than code EC-2 [1] (coefficient of variation δκ=31.9%) (Table 2). Analysis of method of calculation of steel prestress loss due to concrete creep according to the acting code SNiT [2] was made and relationships for linear specific creep of concrete B15—B60 grade were proposed to satisfy the accuracy of practical calculations in the area of regulations of the code [2]. Specific creep relationships presented take into account the most important factors effecting creep deformations: concrete grade, times of loading and observation, scale and ambient humidity, quantity of cement and cement paste. These relationships of specific creep characteristics and the method of evaluation of variation of concrete characteristics can be applied for analysis of concrete structures under the action of long-term loads.

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Han, Bing, Qian Wang, and Yuan Feng Wang. "Creep Modeling for Concrete Filled Steel Tubular Members Compressed with a Large Eccentricity." Advanced Materials Research 150-151 (October 2010): 1343–51. http://dx.doi.org/10.4028/www.scientific.net/amr.150-151.1343.

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Based on concrete creep calculation model B3 and mechanical characteristics of concrete-filled steel tube (CFT) beam-column members of large eccentricity, a creep calculation model of CFT beam-column members of large eccentricity is constructed, which accords with mechanisms of concrete creep, and creep characteristics of concrete core of CFT beam-column members of large eccentricity have been taken into account. The model is verified against previous creep experiments for CFT beam-column specimens, by changing model B3 for ACI209, CEB90, GL2000 model, elastic continuation and plastic flow theory. The results show that introduction of model B3 to predicting creep of CFT beam-column members with a large eccentricity is necessary. Using the model, a study is then carried out on the effects of practical design parameters, such as concrete mix (e.g. water to cement ratio ( ), aggregate to cement ratio ( )), steel ratio and eccentricity ratio, on creep of CFT beam-column members with a large eccentricity.

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Simon, J. P., J. Vander Sloten, R. Van Audekercke, G. Van Der Perre, R. S. M. Ling, G. A. Gie, and G. Fabry. "Finite Element Analysis Applied to Bone Remodelling in Revision Arthroplasty of the Femur using Morselized Allograft and Cement." HIP International 8, no. 2 (January 1998): 51–61. http://dx.doi.org/10.1177/112070009800800211.

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Finite element models have extensively been developed and reported for primary cemented and uncemented total hip replacement, but not for revision arthroplasty of the hip. A two-dimensional equivalent thickness model was developed of the proximal femur with bone grafts, a thin but uniform cement layer and a standard femoral component. This model represents the reconstructed femoral revision setting described by Gie et al (1). The effects of surface texture, cement-stem friction, cement creep and stem malplacement were evaluated. Within the range of coefficients of friction which was investigated in this study (0.03, 0.136 and 0.3) it was observed that the influence of the value of the coefficient upon the stresses in the bone-implant structure are less than 5%. Also static cement creep and certain stem malalignments which were simulated showed a relatively small influence upon the stress distribution within this structure. An agreement between trabecular orientations in the remodeled bone allograft and the principal stress orientations in this structure was observed in the calcar region. It was concluded that the remodelling which occurs in the bone allografts follows Wolff's law of optimal material use in the trabecular structure.

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Niewiadomski, Paweł, and Damian Stefaniuk. "Creep Assessment of the Cement Matrix of Self-Compacting Concrete Modified with the Addition of Nanoparticles Using the Indentation Method." Applied Sciences 10, no. 7 (April 3, 2020): 2442. http://dx.doi.org/10.3390/app10072442.

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In recent years, there has been an increased interest in the modification of cement composites with finer materials, including nanoparticles. Multi-scale studies are needed to fully assess the effect of nanoparticles and provide a complete overview of their impact on both the structure of an obtained material and its important mechanical parameters, such as creep. Therefore, the purpose of this paper is to fill the knowledge gap in the literature concerning the assessment of the creep of a cement matrix of self-compacting concrete modified with the addition of SiO2, TiO2, and Al2O3 nanoparticles using the indentation method. Depending on the type of used nanoparticles, we found an increase or decrease of the creep coefficient CIT in comparison to the reference series. The obtained results were scrupulously analyzed in terms of statistics, which enabled the conclusion that the addition of nanoparticles does not significantly affect the creep of the cement matrix of self-compacting concrete. The methodology used in this paper allowed us to shorten the time needed to assess the creep phenomenon compared to traditional methods and fill the corresponding knowledge gap in the literature.

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Xie, You-jun, Qiang Fu, Guang-cheng Long, Ke-ren Zheng, and Hao Song. "Creep properties of cement and asphalt mortar." Construction and Building Materials 70 (November 2014): 9–16. http://dx.doi.org/10.1016/j.conbuildmat.2014.07.103.

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Verdonschot, Nico, and Rik Huiskes. "Dynamic creep behavior of acrylic bone cement." Journal of Biomedical Materials Research 29, no. 5 (May 1995): 575–81. http://dx.doi.org/10.1002/jbm.820290504.

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Harper, E. J. "Bioactive bone cements." Proceedings of the Institution of Mechanical Engineers, Part H: Journal of Engineering in Medicine 212, no. 2 (February 1, 1998): 113–20. http://dx.doi.org/10.1243/0954411981533881.

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Poly (methylmethacrylate) (PMMA) bone cement, used to fix implants into the bone, produces good surgical results if used correctly. However, prostheses do eventually become loose and the breakdown of the cement mantle is a factor in this failure. Limitations of PMMA cement, which lead to problems with the fixation of the implant, include its mechanical characteristics and its influence upon surrounding bone, associated with the polymerization reaction. A bioactive bone cement is particularly designed to produce a better interface between the cement and bone. However, an improvement in mechanical properties, especially fatigue, creep and fracture toughness, are an added necessary requirement to increase the lifetime of a cemented implant. The development of a bioactive cement has been conducted mainly in two ways; firstly, to improve existing PMMA cement by the addition of various bioactive agents and secondly, to design an alternative matrix for the bioactive material to be combined with. The most promising investigations which have been conducted, along with their relative benefits and drawbacks, are discussed.

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Xu, Hao, Ping Wang, Hong-song Lin, and Hua Yan. "Short-Term Creep Experiment of Cement Asphalt Mortar and Its Numerical Simulation." Advances in Materials Science and Engineering 2016 (2016): 1–6. http://dx.doi.org/10.1155/2016/7684641.

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In order to investigate the creep performance of cement asphalt mortar (CA mortar), the field sampling of CA mortar cylinder samples was produced, and all samples were tested on WDW series electric universal testing machine by using uniaxial static creep test at 25°C, and the load stress levels were 0.05 MPa, 0.1 MPa, 0.3 MPa, and 0.5 MPa. The greater the load is, the bigger the creep deformation is. The creep performance was simulated by using Burgers model, and the correlation coefficients between fitting results of Burgers model and experimental results are all greater than 0.9. Based on the requirements of finite element software, the Prony series of Burgers model was obtained, and the short-term creep process of CA mortar was simulated by the finite element software ANSYS. The relative error between simulation results and experimental data is not more than 2.5%, which indicates that the short-creep process of CA mortar can be simulated by ANSYS software. The study results can improve the structural design theory of slab track.

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Nesvetaev, G. V., Y. I. Koryanova, and A. V. Kolleganov. "E-Modulus and Creep Coefficient of Self-Compacting Concretes and Concretes with some Mineral Additives." Solid State Phenomena 284 (October 2018): 963–69. http://dx.doi.org/10.4028/www.scientific.net/ssp.284.963.

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The applicability of a proposed model similar to a well-known Hirsch's model for predicting the E-modulus of concrete and the creep coefficient of concrete depending on the composition of the concrete, the properties of the components of concrete mix and the possible effect of the superplasticizer on the deformation properties of cement stone both under short-term and long-term loading is proved. Value of the E-modulus of self-compacting concrete can be reduced to 20% with respect to the ordinary concrete of equal compressive strength, which is confirmed by the model calculation data and some experimental data. For concretes with mineral additives, the influence of mineral additives on the E-modulus was not established. Both an increase and decrease in the E-modulus is possible. The effect depends on the type of additive. The creep coefficient of self-compacting concrete, obtained by calculation according to the model, due to the increased content of cement stone and the possible influence of superplasticizer on the creep of cement stone, can be from 1.3 to 1.8 of the coefficient of creep of ordinary concrete. This result agrees well with some experimental data. The creep coefficient of concrete with mineral additives (silica fume, white ash and metakaolin), obtained by calculation according to the model, can be from 0.5 to 0.6 of the coefficient of creep of ordinary concrete. This result agrees well with some experimental data.

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Setti, Vijaya Kumar, B. Dean Kumar, and B. L. P. Swami. "Creep Strain Behaviour of Triple-Blended Steel Fiber Self-Compacting Concrete." IOP Conference Series: Earth and Environmental Science 982, no. 1 (March 1, 2022): 012010. http://dx.doi.org/10.1088/1755-1315/982/1/012010.

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Abstract The objective of the research article is to present the experimental results on the creep strain behaviour of steel fiber Self-Compacting Concrete (SFSCC). In respect of binder content, aggregate size, fine-to-coarse aggregate ratio, water-to-cement ratio, and chemical admixtures, Self-Compacting Concrete (SCC) differentiates from conventional cement concrete. Steel fibers are also inserted into SCC at a predetermined percentage to reinforce it. Steel fibers have been shown to contribute to improved strength characteristics, a dense mass of concrete with little or no voids, reduced pores in concrete, a higher Young’s modulus, and fewer deflections and strains in concrete. Hence, an investigation was conducted on the creep variation of SFSCC over a longer duration. The test approach follows ASTM C512’s standard test method for concrete creep in compression. The test specimens (SFSCC) are standard cylinders that have been cast and cured for 28 days before being tested. Three SFSCC cylinders with 0.80% steel fiber were tested at the same time. The load is applied to just the cylinders in the loading frame and kept constant, producing constant stress. The strains that occur only due to creep, excluding the initial elastic strain, are digitally recorded. As a logarithmic function, the creep strain-time connection was established. The conclusions are observed based on the findings of the experiments and compared with normal cement concrete (NCC).

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Do, Huy Quang, Shashank Bishnoi, and Karen Louise Scrivener. "Microstructural modelling of autogenous shrinkage in Portland cement paste at early age." Engineering Computations 37, no. 9 (May 4, 2020): 3171–86. http://dx.doi.org/10.1108/ec-08-2019-0353.

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Purpose This paper aims to develop a numerical, micromechanical model to predict the evolution of autogenous shrinkage of hydrating cement paste at early age (up to 7 days). Autogeneous shrinkage can be important in high-performance concrete characterized by low water to cement (w/c) ratios. The occurrence of this phenomenon during the first few days of hardening may result in early-age cracking in concrete structures. A good prediction of autogeneous shrinkage is necessary to achieve better understanding of the mechanisms and the deployment of effective measures to prevent early-age cracking. Design/methodology/approach Three-dimensional digital microstructures from the hydration modelling platform μic of cement paste were used to simulate macroscopic autogenous shrinkage based on the mechanism of capillary tension. Elastic and creep properties of the digital microstructures were calculated by means of finite element (FE) method homogenization. Autogenous shrinkage was then estimated as the average hydrostatic strain resulting from the capillary stress that was globally applied on the simulated digital microstructures. For this estimation, two approaches of homogenization technique, i.e. analytical poro-elasticity and numerical creep-superposition were used. Findings The comparisons of between the simulated and experimentally measured deformations indicate that the creep-superposition approach is more reasonable to estimate shrinkage at different water to cement ratios. It was found that better estimations could be obtained at low degrees of hydration, by assuming a loosely packed calcium silicate hydrates (C-S-H) growing in the microstructures. The simulation results show how numerical models can be used to upscale from microscopic characteristics of phases to macroscopic composite properties such as elasticity, creep and shrinkage. Research limitations/implications While the good predictions of some cement paste properties from the microstructure at early age were obtained, the current models have several limitations that are needed to overcome in the future. Firstly, the limitation of pore-structure representation is not only from lack understanding of C-S-H structure but also from the computational complexity. Secondly, the models do not consider early-age expansion that usually happens in practice and appears to be superimposed on an underlying shrinkage as observed in experiments. Thirdly, the simplified assumptions for mechanical simulation do not accurately reflect the solid–liquid interactions in the real partially saturated system, for example, the globally applying capillary stress on the boundary of the microstructure to find the effective deformation, neglecting water flow and the pore pressure. Last but not least, the models, due to the computational complexities, use many simplifications such as FE approximation, mechanical phase properties and creep statistical data. Originality/value This study holistically tackles the phenomenon of autogeneous shrinkage through microstructural modelling. In a first such attempt, the authors have used the same microstructural model to simulate the microstructural development, elastic properties, creep and autogeneous shrinkage. The task of putting these models together was not simple. The authors have successfully handled several problems at each step in an elegant manner. For example, although several earlier studies have pointed out that discrete models are unable to capture the late setting times of cements due to mesh effects, this study offers the most effective solution yet on the problem. It is also the first time that creep and shrinkage have been modelled on a young evolving microstructure that is subjected to a time variable load.

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Nesvetaev, G. V., Y. I. Koryanova, T. N. Zhilnikova, and A. V. Kolleganov. "To the Problem of Assessing the Level of Self- Stresses during the Formation of the Structure of Self-Compacting Concrete." Materials Science Forum 974 (December 2019): 293–98. http://dx.doi.org/10.4028/www.scientific.net/msf.974.293.

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Conditional quantitative criteria characterizing the shrinkage crack resistance of various concretes and a model describing the change in the proposed criteria depending on the magnitude of shrinkage deformation, creep coefficient, tensile strength kinetics and shrinkage strain kinetics for ordinary concrete and self-compacting concrete are proposed. The proposed criteria for the class C40/50 concrete have been calculated and it was shown that self-compacting concrete can potentially have higher crack resistance during shrinkage. To ensure high cracking resistance during shrinkage when choosing superplasticizers and mineral additives, attention should be paid to their effect on shrinkage, creep and E-modulus of the cement stone. It should exclude additives that increase the shrinkage and E-modulus and reduce creep of cement stone.

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Seibi, Abdennour C., Fatick Nath, Adedapo B. Adeoye, and Kaustubh G. Sawant. "Optimization of Cement–Rubber Composites for Eco-Sustainable Well Completion: Rheological, Mechanical, Petrophysical, and Creep Properties." Energies 15, no. 8 (April 8, 2022): 2753. http://dx.doi.org/10.3390/en15082753.

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To ensure well integrity, wellbore must be strongly cased using durable cement slurries with essential additives during downhole completion. The rubber materials that come from industrial waste are becoming extremely encouraged in the use as an additive in preparing cement slurries due to their growing environmental footprint. However, the proper design of cement slurry strongly depends on its rheological, mechanical, petrophysical, and creep properties, which can be altered by changing additives. This study aimed to examine the cement properties under alteration in different chemical admixtures to create efficient binding properties, and to estimate the optimum cement–rubber slurry composition for eco-sustainable completion. Three cement samples with different mesh sizes of the crumb rubber particles were prepared. This study examined the variation in rheological behaviors, elastic and failure characteristics, permeability, and creep behavior of the cement–rubber composites for petroleum well construction. The experimental study showed that the addition of 15% or more crumb rubber to the cement resulted in very thick slurries. Moreover, it was shown that the addition of crumb rubber with various particle sizes to the cement reduced the strength by more than 50%, especially for a higher amount of rubber added. It was also revealed that the addition of a superplasticizer resulted in an 11% increase in compressive strength. The results showed that cement–crumb-rubber composites with 12% by weight of cement (BWOC) represented the optimum composite, and considerably improved the properties of the cement slurry. Water-permeability tests indicated the addition of 12% BWOC with 200-mesh crumb rubber decreased the permeability by nearly 64% compared to the base cement. Creep tests at five different stress levels illustrated that the neat cement was brittle and did not experience strain recovery at all stress levels. Cement slurries with the largest rubber-particle size were elastic and demonstrated the highest amount of strain recovery. Finally, a relationship was established between the permeability, average strain, and mesh size of the rubber particles, which offered the strain recovery, satisfied the zonal isolation, and consequently reduced the microannulus problem to ensure the cement’s integrity.

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MITANI, Yuji, Takuya OHNO, Yusuke ISHII, and Ippei MARUYAMA. "SHRINKAGE REDUCTION EFFECTS AND CREEP PROPERTY OF CONCRETE USING SHRINKAGE REDUCING AGENT." Cement Science and Concrete Technology 70, no. 1 (2016): 336–41. http://dx.doi.org/10.14250/cement.70.336.

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36

Gu, Shui-Tao, Benoît Bary, Qi-Chang He, and Minh-Quan Thai. "Multiscale poro-creep model for cement-based materials." International Journal for Numerical and Analytical Methods in Geomechanics 36, no. 18 (October 3, 2011): 1932–53. http://dx.doi.org/10.1002/nag.1080.

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37

Jones, Christopher A., and Zachary C. Grasley. "Short-term creep of cement paste during nanoindentation." Cement and Concrete Composites 33, no. 1 (January 2011): 12–18. http://dx.doi.org/10.1016/j.cemconcomp.2010.09.016.

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Ghosh, Sujit, and K. W. Nasser. "Creep, shrinkage, frost, and sulphate resistance of high strength concrete." Canadian Journal of Civil Engineering 22, no. 3 (June 1, 1995): 621–36. http://dx.doi.org/10.1139/l95-071.

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A comprehensive study was undertaken to determine the shrinkage, creep, and durability of high strength concrete (50–70 MPa) containing silica fume and lignite fly ash. The concrete mixtures contained normal CSA type 10 (ASTM type 1) portland cement, 10% condensed silica fume, and different amounts of fly ash that varied between 0 and 80% of the weight of binder in the mixture. The aggregates-to-binder ratio by weight was maintained at 5 and the weight of the superplasticizer was varied between 1.5% and 2.2% of the binder while the water-to-binder ratio was maintained at 0.27. The test program consisted of compressive strength tests at various ages on concrete cylinders; drying shrinkage tests at room temperature; creep tests of sealed and unsealed concrete at room temperature (21 °C (70°F)) and at high temperatures (up to 232 °C (450°F)) under three different stress regimes; frost resistance tests on concrete prisms up to 300 freezing and thawing cycles; and sulphate resistance tests on concrete prisms immersed in 5% Na2SO4 solution for up to 10 months. The results indicated that up to 60% fly ash replacement with 10% silica fume showed either superior or similar 28- and 56-day compressive strengths when compared with the 100% cement control mixture. Fly ash + silica fume concrete indicated lower shrinkage and long-term creep. Creep increased with increase in temperature due to physico-chemical processes, which were confirmed by microstructure analysis using the scanning electron microscope. The creep and shrinkage data of high fly ash + silica fume concrete fitted well to the current ACI creep and shrinkage model. Replacement of cement by up to 35% fly ash and 10% silica fume indicated enhanced frost resistance, without any air-entrainment. The addition of 8% air-entrainment to the 20% fly ash + 10% silica fume mixture increased the durability factor by about 10%. For the 50% fly ash + 10% silica fume mixture, the frost durability factor was found comparable to that of the 100% cement control mixture, and air entrainment did not improve its value appreciably. Sulphate resistance of concrete made with 100% CSA type 10 cement was found satisfactory; however, with increasing fly ash contents (up to 50%), the expansion due to sulphate action was suppressed. A study of matrix morphology and microstructure bonding, using the scanning electron microscope, helped to explain the observed results in a comprehensive manner. Key words: creep, shrinkage, compressive strength, frost resistance, durability factor, sulphate resistance, fly ash, silica fume, high-strength concrete, SEM micrograph, matrix morphology.

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Wyrzykowski, Mateusz, Karen Scrivener, and Pietro Lura. "Basic creep of cement paste at early age - the role of cement hydration." Cement and Concrete Research 116 (February 2019): 191–201. http://dx.doi.org/10.1016/j.cemconres.2018.11.013.

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Colorado, Henry A., Elkin I. Gutiérrez-Velásquez, and Clem Hiel. "Cantilever creep method for testing ceramic composites and a case study for chemically bonded phosphate ceramic composites reinforced with glass, carbon and basalt fibers, including both experiments and simulations." Journal of Composite Materials 54, no. 20 (January 23, 2020): 2663–76. http://dx.doi.org/10.1177/0021998320902221.

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This paper presented the cantilever beam experiments and the method for creep in chemically bonded ceramics reinforced with glass, carbon, and basalt unidirectional fibers. The ceramic composite samples were fabricated by mixing wollastonite powder and phosphoric acid, through the resonant acoustic mixing technique. The reinforced fibers were added via pultrusion process. The manufactured materials were exposed to high temperature creep tests at 600, 800 and 1000℃, with an annealing time of 1 h, all in air environment. Some examples of real large-scale structures made manually by a company were also included. In order to understand the microstructure, X-ray diffraction and scanning electron microscopy analysis were included. The presented method is simple and can be used in any inorganic ceramic slurry types, such as geopolymers, phosphate cements, clay-based materials, or Portland cement composites. The sample response in high temperature creep experiments was analyzed with a new but very simple technique, and modeled using finite element analysis over all compositions. Results revealed that fibers have a significant effect on the composite creep when compared to the ceramic without reinforcement, and particularly carbon fibers showed a quite interested effect in reducing the creep effects. Results show the limit of the materials under conditions typically found in fires and other extreme environments.

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Xiong, Xue Yu, Li Jun Wang, Rong Jun Xue, and Sen Zhang. "Creep Behavior of High-Performance Concrete." Advanced Materials Research 919-921 (April 2014): 1885–89. http://dx.doi.org/10.4028/www.scientific.net/amr.919-921.1885.

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Realistic prediction of concrete creep is of crucial importance for the safety, durability and long term serviceability of concrete structures. High performance concrete (HPC) contains combinations of various components, such as aggregate, cement, water-reducing agent and other ingredients which affect the properties of the HPC including creep. This paper reviews the accuracy of the conventional concrete (CC) creep prediction models, including B3,GL2000 and CEB-FIP(2010). Further, a new creep prediction model based on the comprehensive analysis is proposed. The improved model was calibrated through a joint optimization of laboratory creep tests. Comparisons of the results of the proposed methold with 76 data points of creep coefficient showes good agreement.

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Sprince, Andina, Aleksandrs Korjakins, and Leonids Pakrastinsh. "Creep Behaviour of Concrete With Glass Waste Microfiller." Environment. Technology. Resources. Proceedings of the International Scientific and Practical Conference 2 (August 5, 2015): 125. http://dx.doi.org/10.17770/etr2011vol2.1003.

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Every year there are several hundred tons of waste glass produced in Latvia. Glass can be re-used as a fine raw material and it presents a possibility to save natural, non-renewable materials. The use of glass powder in concrete production can make the construction industry more environmentally friendly. This paper examines the possibility of using glass powder as cement replacement in a new type of concrete. In the experiment, cement was partially (20% and 40%) replaced with glass powder. The long-term deformation (creep) of this new concrete was monitored. Three different concrete mixtures were batched. Specimens of 20% and 40% cement replacement were compared with the specimens made of standard concrete. The samples were tested in two extreme conditions: in one case they were kept in 100% humidity ensured by preventing the desiccation of the concrete, and in the other case samples were air-dried by preventing them from becoming wet. Compression strength and modulus of elasticity of 7 and 28 days old cubic samples was determined.

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Guo, Fei, Hong Gen Qin, Peng Fei Cao, Guan Guo Liu, and Yun Sheng Zhang. "Analysis on Creep Property and Model of Bridge Girder Concrete with Various Mix Proportions." Applied Mechanics and Materials 368-370 (August 2013): 1487–94. http://dx.doi.org/10.4028/www.scientific.net/amm.368-370.1487.

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Combined with the construction of Jinghang Canal Bridge of Jiangliu highway, shrinkage and creep property of the cast-in-situ high performance concrete of bridge girder was researched. The results showed early shrinkage and creep development of the high performance concrete was relatively rapid, and creep tended to be stable 120 days later. With the admixture increasing, shrinkage and creep of the concrete were reduced. Meanwhile, early creep rate deceased. Similar results applied to the reduction of sand rate and water-cement ratio. Based on creep prediction models both at home and abroad, hyperbolic power function and exponential function model were put forward, taking the influence of material parameter and environmental factors on shrinkage and creep into consideration. In accordance with the model, concrete creep formula was given out and would provide a relatively scientific basis for practical prediction of concrete creep.

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Boháč, Martin, Tomáš Opravil, Eva Bartoníčková, Františka Frajkorová, and Martin Palou. "The Role of Metakaolin Fineness on Rheological Properties of Cement Pastes." Advanced Materials Research 1000 (August 2014): 39–42. http://dx.doi.org/10.4028/www.scientific.net/amr.1000.39.

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Viscoelastic properties of Portland cement-metakaolin fresh pastes were measured using rotational rheometer. In mixtures 10 % of Portland cement was replaced by various fractions of metakaolin with different particle size distribution. The role of the fineness of metakaolin was revealed characterizing flow, adhesion and creep of the fresh pastes.

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Hu, Chang Bin, Mu Lu Du, and Li Juan Wang. "Research of Built-In Temperature and Zero Stress Temperature of Cement Concrete Pavement at Early Ages." Advanced Materials Research 857 (December 2013): 248–55. http://dx.doi.org/10.4028/www.scientific.net/amr.857.248.

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Based on field tests and numerical simulation methods, distribution characteristics of early-age built-in temperature of cement concrete pavement constructed in different seasons and pouring time were analyzed firstly. Then considering effect of creep, characteristics of early-age zero stress temperature in cement concrete that built-in temperature of cement concrete pavement constructed in different seasons and pouring time has a great difference. The distributions of built-in temperature along the thickness present nonlinear obviously, and they have four typical types: concave and positive gradient type, concave negative gradient type, convex positive gradient type and convex negative gradient type. Zero stress temperature gradient shows prominently developing process compared with built-in temperature of slab at different ages by the effect of creep. Zero stress temperature of slab poured on am7:00 in summer firstly increase and then decline. Besides, the positive gradient change to negative gradient gradually, and the gradient of zero stress temperature trend to decrease. At last, it is recommended to calculate zero stress temperature of slab consideration of base temperature and the nonlinear distributions characteristics, and the combined effect of creep and age.

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Waanders, Daan, Dennis Janssen, Kenneth A. Mann, and Nico Verdonschot. "The effect of cement creep and cement fatigue damage on the micromechanics of the cement–bone interface." Journal of Biomechanics 43, no. 15 (November 2010): 3028–34. http://dx.doi.org/10.1016/j.jbiomech.2010.06.031.

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ASHIZAWA, Ryoichi, Toshiaki MIZOBUCHI, and Hiroki IZUMI. "EVALUATION FOR APPERENT INSTANTANEOUS STIFFNESS DECREASE CONSIDERING EFFECT OF CREEP OF EARLY AGE CONCRETE." Cement Science and Concrete Technology 73, no. 1 (March 31, 2020): 200–207. http://dx.doi.org/10.14250/cement.73.200.

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Liang, Siming, and Ya Wei. "Effects of water-to-cement ratio and curing age on microscopic creep and creep recovery of hardened cement pastes by microindentation." Cement and Concrete Composites 113 (October 2020): 103619. http://dx.doi.org/10.1016/j.cemconcomp.2020.103619.

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Chen, Xiao Bo, Jian Yin, and Wei Min Song. "Autogenous Volume Deformation and Creep Properties Analysis of C60 High Performance Concrete and C60 High Strength Concrete." Advanced Materials Research 639-640 (January 2013): 364–67. http://dx.doi.org/10.4028/www.scientific.net/amr.639-640.364.

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Based on engineering practice, autogenous volume deformation and creep properties of C60 high performance concrete(C60 HPC) and C60 high strength concrete(C60 HSC) were evaluated in the study. The results showed that the cement partly-replaced with fly ash could significantly decrease the creep deformation, creep coefficient and creep degree. In comparison with C60 HSC, the creep coefficient and creep degree of C60 HPC were decreased 17.9％and15.8％ in 28 days, 22.9% and 21.0% in 270 days. For C60 HPC and C60 HSC at the same age, autogenous volume deformation of C60 HPC is greater than that of C60 HSC, but they were both less than 80×10-6 , and the autogenous volume deformation was basically completed in 7 days.

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Wang, Dang Zai, Jian Da Xin, and Zhen Hong Wang. "Creep Behavior of Early-Age Concrete Made with Different Cement Compositions under the Controlled Temperature History." Key Engineering Materials 923 (June 28, 2022): 163–68. http://dx.doi.org/10.4028/p-03013y.

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A temperature stress testing machine (TSTM) was used to investigate effect of cement composition on cracking sensitivity and creep behavior of concrete. Results show that the cracking sensitivity of concrete varied with the ratio of C3S/C2S and it is observed that the temperature difference of concrete linearly increased with smaller ratio of C3S/C2S. Furthermore, it is also found that concrete with higher ratio of C3S/C2S had weaker creep behavior based on the specific creep deduced from results of TSTM.

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Journal articles on the topic 'Cement creep'

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