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Dissertations / Theses on the topic 'Load factor design'

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Published: 4 June 2021
Last updated: 28 July 2024

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1

Saxena, Vishal. "Interval finite element analysis for load pattern and load combination." Thesis, Available online, Georgia Institute of Technology, 2004:, 2003. http://etd.gatech.edu/theses/available/etd-04072004-180207/unrestricted/saxena%5Fvishal%5F200312%5Fms.pdf.

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2

Penketgorn, Thiwa. "Load and resistance factor design for wood structures." Thesis, Virginia Polytechnic Institute and State University, 1985. http://hdl.handle.net/10919/104535.

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3

Townson, Peter Gerard Allan Luke. "Load-maintenance interaction : modelling and optimisation /." [St. Lucia, Qld.], 2002. http://adt.library.uq.edu.au/public/adt-QU20021108.134015/index.html.

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4

Reyburn, Elizabeth Maury. "The design of offshore structures using load and resistance factor design." Thesis, Georgia Institute of Technology, 1994. http://hdl.handle.net/1853/19978.

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5

Patterson, M. J. "Gender and physical training effects on soldier physical competencies and physiological strain." Fishermans Bend, Vic. : Defence Science and Technology Organisation, 2005. http://hdl.handle.net/1947/4680.

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6

Chen, Jou-Jun Robert. "Load and resistance factor design of shallow foundations for bridges." Thesis, Virginia Tech, 1989. http://hdl.handle.net/10919/44627.

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Load Factor Design (LFD), adopted by AASHTO in the mid-1970, is currently used for bridge superstructure design. However, the AASHTO specifications do not have any LFD provisions for foundations. In this study, a LFD format for the design of shallow foundations for bridges is developed.

Design equations for reliability analysis are formulated. Uncertainties in design parameters for ultimate and serviceability limit states are evaluated. A random field model is employed to investigate the combined inherent spatial variability and systematic error for serviceability limit state. Advanced first order second moment method is then used to compute reliability indices inherent in the current AASHTO specifications. Reliability indices for ultimate and serviceability limit states with different safety factors and dead to live load ratios are investigated. Reliability indices for ultimate limit state are found to be in the range of 2.3 to 3.4, for safety factors between 2 and 3. This is shown to be in good agreement with Meyerhof's conclusion (1970). Reliability indices for serviceability limit state are found to be in the range of 0.43 to 1.40, for ratios of allowable to actual settlement between 1.0 to 2.0. This appears to be in good agreement with what may be expected. Performance factors are then determined using target reliability indices selected on the basis of existing risk levels.


Master of Science
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7

Shin, Dong Ku. "Minimum-weight design of symmetrically laminated composite plates for postbuckling performance under in-plane compression loads." Diss., This resource online, 1990. http://scholar.lib.vt.edu/theses/available/etd-07282008-135134/.

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8

Simonpietri, Sean. "Influence of the LRFD moment magnification procedure on unbraced frames in short buildings." Thesis, This resource online, 1992. http://scholar.lib.vt.edu/theses/available/etd-09122009-040427/.

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9

Gandiaga, Lorehana. "Serviceability limits and economical bridge design." Laramie, Wyo. : University of Wyoming, 2009. http://proquest.umi.com/pqdweb?did=1939207291&sid=1&Fmt=2&clientId=18949&RQT=309&VName=PQD.

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10

Ross, Justin Henry. "Evaluating ultimate bridge capacity through destructive testing of decommissioned bridges." Access to citation, abstract and download form provided by ProQuest Information and Learning Company; downloadable PDF file, 154 p, 2007. http://proquest.umi.com/pqdweb?did=1338919151&sid=8&Fmt=2&clientId=8331&RQT=309&VName=PQD.

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Thesis (M.C.E.)--University of Delaware, 2007.
Principal faculty advisors: Michael J. Chajes and Jennifer Righman McConnell, Dept. of Civil & Environmental Engineering. Includes bibliographical references.
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11

Prasad, Badri Krishnamurthy 1959. "Experimental investigation of sleeved columns." Thesis, The University of Arizona, 1989. http://hdl.handle.net/10150/277134.

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Results of experimental tests are presented for twelve 'Sleeved Column' specimens. All the specimens had an outer sleeve and an inner core, both of rectangular cross section. Outer sleeve was 23 in. long and the inner core was 23.5 in., with axial load applied only to the core. There was a gap between the sleeve and the core for all specimens except for one which had zero gap. The parameters considered for the study were core thickness and gap. It was concluded from the study that the sleeved column system carries substantially more load than the conventional Euler's column. The stiffness of the core and the gap between the sleeve and the core affects the load carrying capacity of sleeved column system significantly. For the same core size, specimens with least gap carried more load when compared to other specimens with larger gaps.
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12

Roberts, Lance Alan Misra Anil. "Reliability-based design and analysis of deep foundations at the service limit state." Diss., UMK access, 2006.

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Thesis (Ph. D.)--School of Computing and Engineering and Dept. of Geosciences. University of Missouri--Kansas City, 2006.
"A dissertation in engineering and geosciences." Advisor: Anil Misra. Typescript. Vita. Title from "catalog record" of the print edition Description based on contents viewed Jan. 29, 2007. Includes bibliographical references (leaves 200-206). Online version of the print edition.
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13

Chaudhari, Subodh. "Load based energy savings in three phase squirrel cage induction motors." Morgantown, W. Va. : [West Virginia University Libraries], 2004. https://etd.wvu.edu/etd/controller.jsp?moduleName=documentdata&jsp%5FetdId=3749.

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Thesis (M.S.)--West Virginia University, 2004.
Title from document title page. Document formatted into pages; contains x, 147 p. : ill. (some col.). Includes abstract. Includes bibliographical references (p. 117-121).
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14

Marathe, Anup Ramesh. "Buckling of dome structure with opening, under wind load." To access this resource online via ProQuest Dissertations and Theses @ UTEP, 2009. http://0-proquest.umi.com.lib.utep.edu/login?COPT=REJTPTU0YmImSU5UPTAmVkVSPTI=&clientId=2515.

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15

Moynahan, Nathan A. "Development of a vehicle road load model for ECU broadcast power verification in on-road emissions testing." Morgantown, W. Va. : [West Virginia University Libraries], 2005. https://eidr.wvu.edu/etd/documentdata.eTD?documentid=4454.

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Thesis (M.S.)--West Virginia University, 2005.
Title from document title page. Document formatted into pages; contains xi, 117 p. : ill. (some col.), col. map. Includes abstract. Includes bibliographical references (p. 75-77).
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16

Atadero, Rebecca Anne. "Development of load and resistance factor design for FRP strengthening of reinforced concrete structures." Connect to a 24 p. preview or request complete full text in PDF format. Access restricted to UC campuses, 2006. http://wwwlib.umi.com/cr/ucsd/fullcit?p3210643.

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Thesis (Ph. D.)--University of California, San Diego, 2006.
Title from first page of PDF file (viewed June 7, 2006). Available via ProQuest Digital Dissertations. Vita. Includes bibliographical references (p. 385-392).
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17

Juneja, Lokesh Kumar. "Multiaxial fatigue damage model for random amplitude loading histories." Thesis, Virginia Tech, 1992. http://hdl.handle.net/10919/41522.

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In spite of many multiaxial fatigue life prediction methods proposed over decades of research, no universally accepted approach yet exists. A multiaxial fatigue damage model developed for approximately proportional random amplitude loading is proposed in this study. A normal strain based analysis incorporating the multiaxial state of stress is conducted along a critical orientation assuming a constant strain ratio. The dominant deformation direction is chosen to be the critical orientation which is selected with the help of a principal strain histogram generated from the given multiaxial loading history. The uniaxial cyclic stress-strain curve is modified for the biaxial state of stress present along the critical orientation for the plane stress conditions. Modified versions of Morrow's and of Smith, Watson, and Topper's (SWT) mean-stress models are used to incorporate mean stresses. A maximum shear strain based analysis is, in addition, conducted to check for the shear dominant fatigue crack growth possibility along the critical direction. The most damaging maximum shear strain is chosen after analyzing the in-plane and the two out-of-plane shear strains.

The minimum of the two life values obtained from SWT model and the shear strain model is compared with the life estimated by the proposed model with the modified Morrow's mean stress model. The former is essentially the life predicted by Socie. The results of the proposed model, as reduced to the uniaxial case, are also compared with the experimental data obtained by conducting one-channel random amplitude loading history experiments.
Master of Science

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18

Dale, Kenneth William 1971. "Behaviour of tubular connections under variable repeated loads." Monash University, Dept. of Civil Engineering, 2001. http://arrow.monash.edu.au/hdl/1959.1/8848.

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19

Vimalaraj, Panchalingam. "A simple equation for bearing capacity of a shallow foundation." abstract and full text PDF (free order & download UNR users only), 2006. http://0-gateway.proquest.com.innopac.library.unr.edu/openurl?url_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&res_dat=xri:pqdiss&rft_dat=xri:pqdiss:1438933.

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20

Clingenpeel, Beth F. "The economical use of high performance steel in slab-on-steel stringer bridge design." Morgantown, W. Va. : [West Virginia University Libraries], 2001. http://etd.wvu.edu/templates/showETD.cfm?recnum=2235.

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Thesis (M.S.)--West Virginia University, 2001.
Title from document title page. Document formatted into pages; contains xiii, 148 p. : ill. (some col.). Includes abstract. Includes bibliographical references (p. 136-137).
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21

Na, Gwang-Seok. "Load-displacement behavior of frame structures composed of fiber reinforced polymeric composite materials." Diss., Atlanta, Ga. : Georgia Institute of Technology, 2008. http://hdl.handle.net/1853/26699.

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Thesis (Ph.D)--Civil and Environmental Engineering, Georgia Institute of Technology, 2009.
Committee Chair: Dr. Leroy Z. Emkin; Committee Co-Chair: Dr. Abdul-Hamid Zureick; Committee Member: Dr. Dewey H. Hodges; Committee Member: Dr. Kenneth M. Will; Committee Member: Dr. Rami M. Haj-ali. Part of the SMARTech Electronic Thesis and Dissertation Collection.
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22

Parker, Walter P. "Proposed New Military Live Load for Highway Bridges in the United States." ScholarWorks@UNO, 2019. https://scholarworks.uno.edu/td/2631.

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This thesis presents the results of a mathematical analysis of various live load combinations on highway bridge spans up to 304.8 meters (1,000 feet) total lengths. The analysis included continuous beams, but only the results for simple beams is presented. The analysis was performed using an independently developed Microsoft EXCEL spreadsheet computation, based on superposition and classical mechanics. In this thesis, several actual bridge live loadings and several hypothetical live loadings were analyzed and compared to the American Association of State Highway and Transportation Officials Load and Resistance Factor Design method. Also considered was the new bridge design method adopted by the Louisiana Department of Transportation in March 2015. The evolution of bridge design loads is discussed, and the concept of the Military Load Classification is introduced and adapted to the bridge design analysis. The results of the analysis are presented, compared and interpreted for use in future bridge design.
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23

Dinegdae, Yared Hailegiorgis. "Reliability-based Design Procedure for Flexible Pavements." Licentiate thesis, KTH, Byggvetenskap, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-165280.

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Load induced top-down fatigue cracking has been recognized recently as a major distress phenomenon in asphalt pavements. This failure mode has been observed in many parts of the world, and in some regions, it was found to be more prevalent and a primary cause of pavements failure. The main factors which are identified as potential causes of top down fatigue cracking are primarily linked to age hardening, mixtures fracture resistance and unbound layers stiffness. Mechanistic Empirical analytical models, which are based on hot mix asphalt fracture mechanics (HMA-FM) and that could predict crack initiation time and propagation rate, have been developed and shown their capacity in delivering acceptable predictions. However, in these methods, the effect of age hardening and healing is not properly accounted and moreover, these models do not consider the effect of mixture morphology influence on long term pavement performance. Another drawback of these models is, as analysis tools they are not suitable to be used for pavement design purpose. The main objective of this study is to develop a reliability calibrated design framework in load resistance factor design (LRFD) format which could be implemented to design pavement sections against top down fatigue cracking. For this purpose, asphalt mixture morphology based sub-models were developed and incorporated to HMA-FM to characterize the effect of aging and degradation on fracture resistance and healing potential. These sub-models were developed empirically exploiting the observed relation that exist between mixture morphology and fracture resistance. The developed crack initiation prediction model was calibrated and validated using pavement sections that have high quality laboratory data and observed field performance history. As traffic volume was identified in having a dominant influence on predicted performance, two separate model calibration and validation studies were undertaken based on expected traffic volume. The predictions result for both model calibration and validation was found to be in an excellent agreement with the observed performance in the field. A LRFD based design framework was suggested that could be implemented to optimize pavement sections against top-down fatigue cracking. To achieve this objective, pavement sections with various design target reliabilities and functional requirements were analyzed and studied.  A simplified but efficient limit state equation was generated using a central composite design (CCD) based response surface methodology, and FORM based reliability analysis was implemented to compute reliabilities and formulate associated partial safety factors. A design example using the new partial safety factors have clearly illustrated the potential of the new method, which could be used to supplement existing design procedures.

QC 20150427

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24

Cross, Benjamin Thomas. "Analysis of the AASHTO fatigue design provisions for welded steel bridge details using reliability theory." Access to citation, abstract and download form provided by ProQuest Information and Learning Company; downloadable PDF file, 101 p, 2007. http://proquest.umi.com/pqdweb?did=1338919111&sid=6&Fmt=2&clientId=8331&RQT=309&VName=PQD.

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25

Tahmasebinia, Faham. "Numerical modelling of reinforced concrete slabs subject to impact loading." Access electronically, 2008. http://www.library.uow.edu.au/adt-NWU/public/adt-NWU20080716.152001/index.html.

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26

Roling, Matthew John. "Establishment of a suitable dynamic formula for the construction control of driven piles and its calibration for Load and Resistance Factor Design." [Ames, Iowa : Iowa State University], 2010. http://gateway.proquest.com/openurl?url_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&res_dat=xri:pqdiss&rft_dat=xri:pqdiss:1476343.

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27

Perez, Perez Ariel. "Load resistance factor design (LRFD) for driven piles based on dynamic methods with assessment of skin and tip resistance from PDA signals." [Florida] : State University System of Florida, 1998. http://etd.fcla.edu/etd/uf/1998/amd0042/thesis.pdf.

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Thesis (M.E.)--University of Florida, 1998.
Title from first page of PDF file. Document formatted into pages; contains x, 188 p.; also contains graphics. Vita. Includes bibliographical references (p. 185-186).
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28

Kurc, Ozgur. "A Substructure Based Parallel Solution Framework for Solving Linear Structural Systems with Multiple Loading Conditions." Diss., Georgia Institute of Technology, 2005. http://hdl.handle.net/1853/6923.

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This study presented a substructure based parallel linear solution framework for the static analysis of linear structural engineering problems having multiple loading conditions. The framework was composed of two separate programs designed to work on PC Clusters having the Windows operating system. The first program was responsible for creating the optimum substructures for the parallel solution and first partitioned the structure in such a way that the number of substructures was equal to the number of processors. Then, the estimated condensation time imbalance of the initial substructures was adjusted by iteratively transferring nodes from the substructures with slower estimated condensation times to the substructures with faster estimated condensation times. Once the final substructures were created, the second program started the solution. Each processor assembled its substructures stiffness matrix and condensed it to the interface with other substructures. The interface problem was solved by a parallel variable band solver. After computing the interface unknowns, each processor calculated the internal displacements and element stresses or forces. Examples which illustrate the applicability and efficiency of this approach were also presented. In these examples, the number of processors was varied from one to twelve to demonstrate the performance of the overall solution framework.
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29

Robison, Aaron. "Modeling and Validation of Tension-Element Based Mechanisms for Golf Ball-Club Impact." Diss., CLICK HERE for online access, 2006. http://contentdm.lib.byu.edu/ETD/image/etd1523.pdf.

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30

BOY, SERPIL. "RETROFIT OF EXISTING REINFORCED CONCRETE BRIDGES WITH FIBER REINFORCED POLYMER COMPOSITES." University of Cincinnati / OhioLINK, 2004. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1078508332.

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31

Whitezell, Marc A. "Development of a Strain Energy Storage Mechanism Using Tension Elements to Enhance Golf Club Performance." Diss., CLICK HERE for online access, 2006. http://contentdm.lib.byu.edu/ETD/image/etd1258.pdf.

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32

Nation, Cory A. "The "45 Degree Rule" and its Impact on Strength and Stiffness of a Shaft Subjected to a Torsional Load." University of Dayton / OhioLINK, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=dayton1417442309.

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33

Raziq, Noor. "GPS structural deformation monitoring : the mid-height problem /." Connect to thesis, 2008. http://repository.unimelb.edu.au/10187/3340.

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GPS has been used to monitor engineering structures for a number of reasons. One important reason for monitoring high rise buildings (and other engineering structures) is their safety assessment in events of extreme loading, such as earthquakes and storms. Decisions must be made as soon as possible, whether to allow re-occupation of such buildings, or to assess them for further damage. The time required to reach such decisions is cost-critical, both for the building owner or manager and for the agency doing the assessment. Peak inter-storey drift ratio and detection of permanent damage are some of the damage assessment parameters recommended by assessment agencies. Traditionally, accelerometers have been used to monitor these parameters. Accelerometers measure accelerations which are double-integrated to get displacements. These double integrated displacements are then used for computing the inter-storey drift ratios and locating permanent damage. Displacements obtained by double-integration and inter-storey drift ratios by subtraction of these displacements, are often erroneous and unreliable and direct measurement of displacement is preferred. Direct measurement of displacement is required at a number of points along the height of the building. For example, for computing inter-storey drift ratios, measurements of displacement at both the floor level and roof level are required. Such points on buildings and other engineering structures of vertical profile are termed as mid-height points in this thesis. While GPS has been used for deformation monitoring of engineering structures and to assist in damage assessment during and after extreme loading events, its use has been limited to roof top installations.
This research is an attempt to measure displacements at mid-height locations of engineering structures of vertical profile using GPS. (For complete abstract open document).
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34

Wang, Naiyu. "Reliability-based condition assessment of existing highway bridges." Diss., Georgia Institute of Technology, 2010. http://hdl.handle.net/1853/34835.

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Condition assessment and safety verification of existing bridges and decisions as to whether bridge posting is required are addressed through analysis, load testing, or a combination of methods. Bridge rating through structural analysis is by far the most common procedure for rating existing bridges. The American Association of State Highway and Transportation Officials (AASHTO) Manual for Bridge Evaluation (MBE), First Edition permits bridge capacity ratings to be determined through allowable stress rating (ASR), load factor rating (LFR) or load and resistance factor rating (LRFR); the latter method is keyed to the AASHTO LRFD Bridge Design Specifications, which is reliability-based and has been required for the design of new bridges built with federal findings since October, 2007. A survey of current bridge rating practices in the United States has revealed that these three methods may lead to different ratings and posting limits for the same bridge, a situation that carries serious implications with regard to the safety of the public and the economic well-being of communities that may be affected by bridge postings or closures. To address this issue, a research program has been conducted with the overall objective of providing recommendations for improving the process by which the condition of existing bridge structures is assessed. This research required a coordinated program of load testing and finite element analysis of selected bridges in the State of Georgia to gain perspectives on the behavior of older bridges under various load conditions. Structural system reliability assessments of these bridges were conducted and bridge fragilities were developed for purposes of comparison with component reliability benchmarks for new bridges. A reliability-based bridge rating framework was developed, along with a series of recommended improvements to the current bridge rating methods, which facilitate the incorporation of various in situ conditions of existing bridges into the bridge rating process at both component and system levels. This framework permits bridge ratings to be conducted at three levels of increasing complexity to achieve the performance objectives, expressed in the terms of reliability, that are embedded in the LRFR option of the AASHTO Manual of Bridge Evaluation. This research was sponsored by the Georgia Department of Transportation, and has led to a set of Recommended Guidelines for Condition Assessment and Evaluation of Existing Bridges in Georgia.
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Woolley, Brandon H. "An Approach to Concept Development for Compliant Mechanisms Possessing High Coefficients of Restitution." Diss., CLICK HERE for online access, 2003. http://contentdm.lib.byu.edu/ETD/image/etd183.pdf.

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36

Bian, Jian. "Ultimate flexural limit states analysis of prestressed concrete sleeper." Thesis, Queensland University of Technology, 2012. https://eprints.qut.edu.au/63660/1/Jian_Bian_Thesis.pdf.

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Railway is one of the most important, reliable and widely used means of transportation, carrying freight, passengers, minerals, grains, etc. Thus, research on railway tracks is extremely important for the development of railway engineering and technologies. The safe operation of a railway track is based on the railway track structure that includes rails, fasteners, pads, sleepers, ballast, subballast and formation. Sleepers are very important components of the entire structure and may be made of timber, concrete, steel or synthetic materials. Concrete sleepers were first installed around the middle of last century and currently are installed in great numbers around the world. Consequently, the design of concrete sleepers has a direct impact on the safe operation of railways. The "permissible stress" method is currently most commonly used to design sleepers. However, the permissible stress principle does not consider the ultimate strength of materials, probabilities of actual loads, and the risks associated with failure, all of which could lead to the conclusion of cost-ineffectiveness and over design of current prestressed concrete sleepers. Recently the limit states design method, which appeared in the last century and has been already applied in the design of buildings, bridges, etc, is proposed as a better method for the design of prestressed concrete sleepers. The limit states design has significant advantages compared to the permissible stress design, such as the utilisation of the full strength of the member, and a rational analysis of the probabilities related to sleeper strength and applied loads. This research aims to apply the ultimate limit states design to the prestressed concrete sleeper, namely to obtain the load factors of both static and dynamic loads for the ultimate limit states design equations. However, the sleepers in rail tracks require different safety levels for different types of tracks, which mean the different types of tracks have different load factors of limit states design equations. Therefore, the core tasks of this research are to find the load factors of the static component and dynamic component of loads on track and the strength reduction factor of the sleeper bending strength for the ultimate limit states design equations for four main types of tracks, i.e., heavy haul, freight, medium speed passenger and high speed passenger tracks. To find those factors, the multiple samples of static loads, dynamic loads and their distributions are needed. In the four types of tracks, the heavy haul track has the measured data from Braeside Line (A heavy haul line in Central Queensland), and the distributions of both static and dynamic loads can be found from these data. The other three types of tracks have no measured data from sites and the experimental data are hardly available. In order to generate the data samples and obtain their distributions, the computer based simulations were employed and assumed the wheel-track impacts as induced by different sizes of wheel flats. A valid simulation package named DTrack was firstly employed to generate the dynamic loads for the freight and medium speed passenger tracks. However, DTrack is only valid for the tracks which carry low or medium speed vehicles. Therefore, a 3-D finite element (FE) model was then established for the wheel-track impact analysis of the high speed track. This FE model has been validated by comparing its simulation results with the DTrack simulation results, and with the results from traditional theoretical calculations based on the case of heavy haul track. Furthermore, the dynamic load data of the high speed track were obtained from the FE model and the distributions of both static and dynamic loads were extracted accordingly. All derived distributions of loads were fitted by appropriate functions. Through extrapolating those distributions, the important parameters of distributions for the static load induced sleeper bending moment and the extreme wheel-rail impact force induced sleeper dynamic bending moments and finally, the load factors, were obtained. Eventually, the load factors were obtained by the limit states design calibration based on reliability analyses with the derived distributions. After that, a sensitivity analysis was performed and the reliability of the achieved limit states design equations was confirmed. It has been found that the limit states design can be effectively applied to railway concrete sleepers. This research significantly contributes to railway engineering and the track safety area. It helps to decrease the failure and risks of track structure and accidents; better determines the load range for existing sleepers in track; better rates the strength of concrete sleepers to support bigger impact and loads on railway track; increases the reliability of the concrete sleepers and hugely saves investments on railway industries. Based on this research, many other bodies of research can be promoted in the future. Firstly, it has been found that the 3-D FE model is suitable for the study of track loadings and track structure vibrations. Secondly, the equations for serviceability and damageability limit states can be developed based on the concepts of limit states design equations of concrete sleepers obtained in this research, which are for the ultimate limit states.
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Cline, Jason S. "Manipulation of Load Factors for Design Demand by Yielding the Buckling-Restrained Columns." University of Akron / OhioLINK, 2021. http://rave.ohiolink.edu/etdc/view?acc_num=akron162005278371206.

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38

O'Brien, Patrick Emmet. "Characterizing the Load-Deformation Behavior of Steel Deck Diaphragms using Past Test Data." Thesis, Virginia Tech, 2017. http://hdl.handle.net/10919/78679.

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Recent research has identified that current code level seismic demands used for diaphragm design are considerably lower than demands in real structures during a seismic event. However, historical data has shown that steel deck diaphragms, common to steel framed buildings, perform exceptionally well during earthquake events. A new alternative diaphragm design procedure in ASCE 7-16 increases diaphragm seismic demand to better represent expected demands. The resulting elastic design forces from this method are reduced by a diaphragm design force reduction factor, Rs, to account for the ductility of the diaphragm system. Currently, there exist no provisions for Rs factors for steel deck diaphragms. This research was therefore initiated to understand inelastic steel deck diaphragm behavior and calculate Rs factors. A review of the literature showed that a large number of experimental programs have been performed to obtain the in-plane load-deformation behavior of steel deck diaphragms. To unify review of these diaphragm tests and their relevant results, a database of over 750 tested specimens was created. A subset of 108 specimens with post-peak, inelastic behavior was identified for the characterization of diaphragm behavior and ductility. A new recommended method for predicting shear strength and stiffness for steel deck diaphragms with structural concrete fill is proposed along with an appropriate resistance factor. Diaphragm system level ductility and overstrength are estimated based on subassemblage test results and Rs factors are then calculated based on these parameters. The effects of certain variables such as deck thickness and fastener spacing on diaphragm ductility are explored.
Master of Science
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39

Hillinger, Hubertus J. "Loud silence : aging and environment." Virtual Press, 1997. http://liblink.bsu.edu/uhtbin/catkey/1041807.

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The purpose of this paper is to present, illustrate and systematize documentation on projected and existing international examples and housing conditions for an aging population and to question the architect's role in terms of person-environment relations.As architects we often base our design on assumptions. A thorough training in the techniques of systematic observation can provide information, and data for improvements and necessities.The paper consists of two main parts. The first part focuses on research of theoretical and practical design aspects through a retrospective look at the history and the physiology of aging.Major goals are:• To increase the knowledge of person-environment interactions through a better understanding of behavioral systems of older people (environment as a stimulant).• To examine environmental attributes constituting an appropriate environment for an independent life (therapeutic aspects of design).• To identify necessities and ways of filling gaps in the relationship between theoretical design aspects and their practical application.•To refelect on historical aspects of aging by showing the ambivalence and changeability in man's systems of values.The second part of the paper considers several international innovative housing and living arrangements in an illustrative way.
Department of Architecture
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40

Kretzschmar, Gunnar. "The experimental determination of structural design parameters for roof covering systems." Thesis, Stellenbosch : Stellenbosch University, 2011. http://hdl.handle.net/10019.1/18053.

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Thesis (MScEng)--Stellenbosch University, 2011.
ENGLISH ABSTRACT: All structures are designed for a particular set of load combinations. For roof structures the critical loading combinations are predominantly wind actions. The accumulative effect of wind actions, by wind entering through dominant openings to exert pressure on the inside of roof structures together with the suction of wind vortices on the outside of the roof, can contribute to extreme load combinations. Frequently recorded failures on roof structures suggest that either the loads are underestimated or the resisting capacity of the roof coverings is overestimated. The focus of this study is directed on the latter, determining the effective resistance of roof coverings in the form of sheeting against a Uniformly Distributed Load (UDL) such as wind actions. To determine the carrying capacity of a roofing structure, the standard approach used involves experimental tests on certain configurations with two or more spans. The structural test set-up is loaded with sandbags until failure is reached. For the design of roofing systems, design tables are used that list the maximum allowable purlin spacing. The purlin spacing is presented in the form of a fixed value in units of length and is shown independent of a UDL that the roof needs to be designed for. The need to a new approach to determining the resistance of roof covering systems was identified. The resistance of roof coverings for the Ultimate Limit State (ULS) and the Serviceability Limit State (SLS) depends on a number of parameters such as the bending resistance, the stiffness of the sheeting in bending and the carrying capacity of the fastening system. To evaluate these structural parameters, experimental tests were performed. A full-scale experimental test setup, capable of simulating a UDL on roof sheeting, was developed. The experimental test set-up consists of four different configurations, each specifically schematized to evaluate a certain structural design parameter. The magnitude of the structural design parameters depends on the applied UDL and the span length, which is the distance between consecutive supports of the sheeting system. Therefore, by using the structural design parameters determined experimentally, a set of design tables could be generated. The design tables produce the maximum allowable span length of a roofing system that uses a desired UDL as a variable. By using the design tables, the purlin spacing for any roof structure can be calculated given its design loading combination. The calculated purlin spacings are now a function of the basic parameters that determine the resistance of the roof sheeting.
AFRIKAANSE OPSOMMING: Geen opsomming
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41

Arginhan, Oktay. "Reliability Based Safety Level Evaluation Of Turkish Type Precast Prestressed Concrete Bridge Girders Designed In Accordance With The Load And Resistance Factor Desing Method." Master's thesis, METU, 2010. http://etd.lib.metu.edu.tr/upload/12612723/index.pdf.

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The main aim of the present study is to evaluate the safety level of Turkish type precast prestressed concrete bridge girders designed according to American Association of State Highway and Transportation Officials Load and Resistance Factor Design (AASHTO LRFD) based on reliability theory. Span lengths varying from 25 m to 40 m are considered. Two types of design truck loading models are taken into account: H30S24-current design live load of Turkey and HL93-design live load model of AASHTO LRFD. The statistical parameters of both load and resistance components are estimated from local data and published data in the literature. The bias factors and coefficient of variation of live load are estimated by extrapolation of cumulative distribution functions of maximum span moments of truck survey data (Axle Weight Studies) that is gathered from the Division of Transportation and Cost Studies of the General Directorate of Highways of Turkey. The uncertainties associated with C40 class concrete and prestressing strands are evaluated by the test data of local manufacturers. The girders are designed according to the requirements of both Service III and Strength I limit states. The required number of strands is calculated and compared. Increasing research in the field of bridge evaluation based on structural reliability justifies the consideration of reliability index as the primary measure of safety of bridges. The reliability indexes are calculated by different methods for both Strength I and Service III limit states. The reliability level of typical girders of Turkey is compared with those of others countries. Different load and resistance factors are intended to achieve the selected target reliability levels. For the studied cases, a set of load factors corresponding to different levels of reliability index is suggested for the two models of truck design loads. Analysis with Turkish type truck models results in higher reliability index compared to the USA type truck model for the investigated span lengths
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42

Quezada, Eder, Yaneth Serrano, and Guillermo Huaco. "Dynamic Amplification Factor Proposal for Seismic Resistant Design of Tall Buildings with Rigid Core Structural System." Smart Innovation, Systems and Technologies, 2021. http://hdl.handle.net/10757/653773.

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El texto completo de este trabajo no está disponible en el Repositorio Académico UPC por restricciones de la casa editorial donde ha sido publicado.
Currently, there is an increase in the demand for tall buildings in the city of Lima. This research proposes to reduce the dynamic amplification factor through the seismic design of tall buildings based on the requirements of Peruvian code considering that they are regular in plan and height. Minimum base shear values according to the comparison of static seismic shear and dynamic shear from the spectral modal analysis were reviewed for cases of buildings larger than 120 m. The study of 28 reinforced concrete buildings was proposed, with different heights - varying from 24 to 36 floors, with different floor configurations, as well as the arrangement of the walls considering as a rigid core structural system. Additionally, the characteristics of the materials, the loads and combinations were defined. The responses of these buildings were determined by the response spectrum analysis (RSA) and then compared with those obtained by the lineal response history analysis (LRHA), for the last analysis, five Peruvian seismic records were used and scaled to 0.45 g. The seismic responses of the LRHA procedure were taken as a benchmark. The result of this study is the analysis and proposal of the C/R factor for high-rise buildings, as well as obtaining the base shear and drift verification. Minimum base shear values can be reduced for high or long-term buildings, being regular in plan and height.
Revisión por pares
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43

Dallakoti, Pramish Shakti. "Structural Reliability Study of Highway Bridge Girders Based on AASTHO LRFD Bridge Design Specifications." University of Toledo / OhioLINK, 2020. http://rave.ohiolink.edu/etdc/view?acc_num=toledo1588538610400668.

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44

Hegger, Josef, Norbert Will, and Maike Schneider. "Textilbeton." Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2011. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-77969.

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Für die Anwendung des Verbundwerkstoffes „Textilbewehrter Beton“ sind die numerischen und experimentellen Grundlagenerkenntnisse zum Tragverhalten von Bauteilen in für die Baupraxis geeignete Nachweismodelle und Konstruktionsregeln zu überführen. Die aus dem Stahlbetonbau bekannten Ansätze müssen wegen der abweichenden Material- und Verbundeigenschaften für textilbewehrte Betonbauteile angepasst werden. Im Beitrag werden die grundlegenden Tragmechanismen textilbewehrter Elemente unter Zug-, Biege- und Querkraftbeanspruchung sowie punktförmiger Zugbeanspruchung beschrieben und die aus den Untersuchungsergebnissen abgeleiteten Nachweismodelle vorgestellt. Darauf aufbauend werden Sicherheitsbeiwerte für die textile Bewehrung ermittelt und die Berechnungsmodelle in ein Sicherheitskonzept eingebunden. Als einheitlicher Teilsicherheitsbeiwert für Textilbeton wird γtex = 1,5 vorgeschlagen
For the application of the composite material Textile Reinforced Concrete (TRC) the numerical and experimental knowledge of the load bearing behaviour of construction elements has to be transferred into design models and construction rules applicable for the practice. Due to differences in the material and bond properties the design approach known for steel reinforced concrete has to be adjusted for textile reinforced concrete construction parts. In this paper the basic load-bearing mechanisms of textile reinforced concrete under tension, bending and shear loading as well as under concentrated tensile loading are described and empirically derived design models are presented. Based on the experimental results safety factors for the textile reinforcements are determined and the design models are integrated into an overall safety concept. A partial safety factor for textile reinforced concrete of γtex = 1,5 is recommended
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45

Paris, Manuel. "Identification du comportement en torsion à fort facteur d’avancement des pales d’hélicoptère conventionne : application à la réduction des efforts de commandes sur une formule hybride haute vitesse de type X3." Thesis, Paris, ENSAM, 2014. http://www.theses.fr/2014ENAM0045.

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L'augmentation de la vitesse de croisière des hélicoptères à architecture conventionnelle (rotor principal et rotor anticouple) atteint aujourd'hui une asymptote. Le concept X3, associant 2 hélices et une aile pour alléger la charge du rotor principal, propose une solution viable économiquement, qui s'appuie sur l'utilisation de technologies éprouvées telles que le rotor Spheriflex® du Dauphin. Les essais en vol menés sur le démonstrateur X3 ont montré un bon comportement en performances et en qualités de vol de ce type de rotor, mais un niveau de charges très importants dans les commandes de vol. Pour limiter la masse à vide, la solution de surdimensionner toutes les pièces mécaniques n'est pas envisageable. Ce travail de thèse propose d'étudier les opportunités de réduction des efforts de commandes.Afin de pouvoir réduire ces efforts, il a été nécessaire de comprendre leur origine et de proposer une modélisation qui permette de les prédire. Des mesures expérimentales réalisées sur le démonstrateur X3 ont permis d'identifier les excitations aérodynamiques et le comportement dynamique des pales en torsion. Les phénomènes responsables de l'augmentation des efforts de commande ont été identifiés, ce qui a permis de corriger le modèle de calcul des efforts de commande HOST actuellement utilisé par Airbus Helicopters.A partir du logiciel HOST corrigé et de la compréhension des phénomènes physiques, des solutions technologiques pour réduire les efforts de commandes ont été étudiées. Deux familles de solutions sont alors considérées : l'optimisation du système de commandes de vol et la réduction des efforts dans les bielles de pas. L'optimisation du système de commandes de vol permet d'obtenir une réduction significative des efforts de commandes grâce à un algorithme d'optimisation de l'architecture de placement des servocommandes. L'étude de la réduction des efforts dans les bielles de pas montre que le choix de l'équilibre appareil conduit à des opportunités de réduction des efforts de commandes, alors que la modification du design de pale n'apporte pas de réduction notable et engendre une diminution des performances en stationnaire
Nowadays, the increase of cruise speed for conventional helicopters (main rotor and anti-torque rear rotor) reaches an asymptote. The X3 concept proposed by Airbus Helicopters is a hybrid helicopter combining 2 propellers at the tip of small wings in order to unload the main rotor. This solution is economically viable because it reuses well-proven technologies such as the Spheriflex rotor, already used on the Dolphin family for many years. X3 flight tests have shown a good behavior of the rotor concerning performances as well as handling qualities, but control loads in the rotor system were significantly higher in cruise conditions than for conventional helicopters. In order to save the payload, over-sizing of the mechanical parts in order to withstand these loads can't be an appropriate solution. The work presented in this thesis deals with the problematic of control loads reduction.In order to reduce the control loads, the first step is to highlight the roots of these loads and to get a predictive tool over the whole flight domain. Experimental measurements from X3 flight tests give the aerodynamic loads on the blade sections, leading to understand the blades torsional dynamic behavior in several flight test cases (cruise, turns and high speed flight). Phenomena responsible for the increase of control loads are then identified, and the rotor computation tool HOST used at Airbus Helicopters is corrected to predict accurately control loads over the conventional as well as the high speed helicopter flight domain.The corrected rotor computation tool HOST, associated with the physical comprehension of the blade torsional dynamics, is used to quantify the possible solutions proposed for control loads reduction. Two main ways are studied: the optimization of the control system architecture and the reduction of pitch link loads. The optimization of control system architecture shows a dramatic reduction of control loads in the servo actuators and in the non-rotating scissors, thanks to an optimization algorithm developed during this thesis. The reduction of pitch link loads study shows that the optimization of the helicopter equilibrium leads to drastic reduction, whereas the modification of blade design does not show any significant reduction even at high speed
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46

Wirzberger, Maria [Verfasser], Günter Daniel [Akademischer Betreuer] Rey, Günter Daniel [Gutachter] Rey, and Josef F. [Gutachter] Krems. "Load-inducing factors in instructional design: Process-related advances in theory and assessment / Maria Wirzberger ; Gutachter: Günter Daniel Rey, Josef F. Krems ; Betreuer: Günter Daniel Rey." Chemnitz : Technische Universität Chemnitz, 2019. http://d-nb.info/1215909179/34.

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47

Zhang, Qinghe. "Development of skew correction factors for live load shear and reaction distribution in highway bridge design a dissertation presented to the faculty of the Graduate School, Tennessee Technological University /." Click to access online, 2009. http://proquest.umi.com/pqdweb?index=0&did=1707210441&SrchMode=1&sid=2&Fmt=6&VInst=PROD&VType=PQD&RQT=309&VName=PQD&TS=1268938179&clientId=28564.

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48

Sivapathasundaram, Mayooran. "Localised pull-through failures of thin steel roof battens subject to wind uplift loads." Thesis, Queensland University of Technology, 2016. https://eprints.qut.edu.au/204638/1/Mayooran_Sivapathasundaram_Thesis.pdf.

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High wind events such as tropical cyclones, severe storms and tornadoes are more likely to impact the Australian coastal regions due to possible climate changes. Such events can be extremely destructive to building structures, in particular, low-rise buildings with lightweight roofing systems that are commonly made of thin steel roof sheeting and battens. Large wind suction loads that act on the roofs during high wind events cause premature failures of roof connections (fixings), leading to complete roof failures. Past wind damage investigations showed that the roof sheeting to batten connection failed frequently during high wind events. These local connection failures have been extensively investigated by many researchers and suitable recommendations to eliminate such failures have been proposed. However, this meant the weakest point has now shifted to the batten to truss/rafter connection. These connections are predominantly subjected to localised pull-through failures in which the screw fastener head pulls through the bottom flanges of thin steel roof battens. However, these failures have not been investigated adequately despite the many roof batten pull-through failures and eventual losses of both roof sheeting and battens observed after recent high wind events. Currently available design rules for the pull-through capacity of cold-formed steel screw fastener connections do not address the specific pull-through failures in thin steel roof battens under wind uplift loading. Current design practice of roof battens is based on using the design wind uplift capacity tables published by their manufacturers. However, it is unclear whether these design capacity tables developed for specific roof battens adequately included the effects of pull-through failures. As for the roof sheeting to batten connections, batten to rafter/truss connections are also subjected to both static and fatigue failures due to static and cyclic wind uplift loads, respectively. Although some experimental studies were conducted in the past using simulated static and cyclic wind loading, they were incomplete and no design rules were developed. Since the climate predictions indicate the likelihood of severe storm events with increased intensity in the future, they are more likely to cause static pull-through failures of roof battens. In addition, a thorough understanding of the static behaviour is first needed to evaluate the fatigue behaviour in depth. Hence this research was aimed at investigating the localised pull-through failures of thin steel roof battens under simulated static wind uplift loads, using laboratory experiments and finite element modelling. A preliminary and detailed experimental study was first conducted using industrial roof battens and full scale air-box tests and three small scale tests such as two-span batten tests, cantilever batten tests and short batten tests. Suitable small scale test methods were identified to accurately simulate the localised pull-through failures of roof battens. The applicability of the proposed small scale test methods for other roof battens was verified using two-span and short batten tests undertaken using roof battens made at the university workshop. Based on the test results, a suitable modification factor was recommended for use with the pull-through capacity equation presented in the current Australian (AS/NZS 4600: 2005) and American (AISI S100: 2012) cold-formed steel standards to accurately determine the pullthrough failure loads of roof battens. The main and extensive experimental study was then undertaken using two-span and short batten tests to examine the pull-through failures of roof battens. The tests were conducted to investigate the effects of many critical parameters such as screw fastener tightening, batten height, web angle, steel grade, batten thickness, screw fastener head size, screw fastener location, batten bottom flange width, underside and edge details of the screw fastener head, and screw fastener types on the roof batten pull-through failure behaviour and capacity. Since the test results showed that the pull-through failure behaviour of high strength and low strength steel roof battens significantly differed from each other due to the differences in ductility, two new design rules and relevant capacity reduction factors were developed to accurately determine the design pull-through capacities of roof battens. The finite element models of both two-span batten and short batten test specimens were modelled and analysed using ABAQUS software. A suitable failure criterion was developed based on constitutive model inputs and employed in the finite element analyses to accurately predict the initiation of pull-through failures of thin steel roof battens associated with the tearing fracture of bottom flange around the screw fastener head edge. The finite element models were validated using the test results, and additional parametric studies were conducted to investigate the parameters which were not considered in the experimental study due to their lower importance on pullthrough failure behaviour and capacity of roof battens. A large pull-through capacity data base was developed using the pull-through failure loads obtained from the tests and finite element analyses. Suitable design rules were then developed using them and finally recommended with suitable capacity reduction factors for the accurate determination of the design pull-through capacities of thin-walled steel roof battens. This study also investigated the strengthening methods recommended by the roof batten manufacturers and builders and showed that they are inadequate to provide a significant improvement based on the governing pull-through failures of roof battens. A reliable strengthening method using overlapping short battens as brackets at the supports was recommended and a series of roof batten tests was conducted using two-span batten tests and two types of industrial roof battens. The test results confirmed the adequacy of the proposed strengthening method. Suitable fragility curves were developed using detailed probabilistic analyses and Monte Carlo simulations based on the governing pull-through failures of thin steel roof battens to predict the likely level of roof damages to a large community for a given wind speed. The pull-through failure behaviour of roof battens was examined by defining eight different cases that are likely to occur during high wind events (for example, with and without dominant openings) and developing relevant fragility curves. The effects of using different batten span and spacing were also investigated using fragility curves. Fragility curves were also used to evaluate the enhancement level that could be achieved with the proposed strengthening method. In summary, this research study has developed suitable test, design and strengthening methods and fragility curves for thin steel roof battens subject to localised pullthrough failures under high wind uplift loads.
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49

Jatheeshan, Varathananthan. "Numerical and experimental studies of cold-formed steel floor systems made of hollow flange section joists in fire." Thesis, Queensland University of Technology, 2015. https://eprints.qut.edu.au/120145/1/Varathananthan_Jatheeshan_Thesis.pdf.

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The cold-formed steel utilization in buildings has increased globally due to its higher strength to weight ratio, ease of transportation and rapid erection and dismantlement. However, cold-formed steel buildings must be designed with adequate Fire Resistance Ratings (FRR). Hence cold-formed Light gauge Steel Frames (LSF) are assembled using channel sections and lined with fire resistive plasterboards to provide load-bearing wall and floor systems. There is an industry need to develop LSF floor systems with improved FRR. Adding multiple layers of plasterboard to increase the FRR of LSF floor systems is not an efficient method. Past research has focused on investigating the behaviour of LSF floor systems made of Lipped Channel Section (LCS) joists. No attempt has been made to use an improved joist section in LSF floor systems. The Hollow Flange Sections (HFS) with torsionally rigid hollow flanges and no free edges have higher local and lateral distortional buckling capacities than the conventional LCSs. This research focuses on investigating the structural and fire performance of LSF floor systems made of HFS joists with a goal to improve their FRRs. Four full scale standard fire tests were undertaken on non-insulated dual and single plasterboard lined LSF floor panels and cavity insulated dual plasterboard lined floor panel made of welded HFS joists known as LiteSteel beams (LSB). Fire tests of these panels undertaken for varying load ratios provided valuable results, which included failure times, joist temperatures and modes, and deflection versus time curves. The floor panels failed due to the section failures of joists. Both non-insulated and cavity insulated LSF floors made of LSB joists showed a significant improvement in the FRRs in comparison to Baleshan's (2012) results for LSF floors made of LCS joists. Another experimental study was undertaken to determine the elevated temperature mechanical properties of the steel used in LSB web and flange elements. The mechanical property reduction variation of LSB steel elements was found to be quite different to that of normal cold-formed steels and was even dissimilar amongst them. The yield strength reduction factors of Eurocode 3 Part 1.2 (ECS, 2005) were proposed for the web elements since they closely followed them whereas a new yield strength reduction factor model was proposed for the flange elements. An identical variation was proposed for the elastic modulus reduction factors of both web and flange elements. Suitable modifications were made to Dolamune Kankanamge and Mahendran's (2011) stress-strain model for improved predictions of LSB web and flange elements' stress-strain curves. A Finite Element (FE) model of an individual simply supported LSB joist was developed and validated using the cold-formed steel design standards and Anapayan et al.'s (2011b) section moment capacity test results. By using the accurate mechanical property reduction factors of LSB steel elements, the FE model was then extended to simulate the full scale fire tests. Finite element analyses (FEA) showed reasonably good agreements in terms of failure times, temperatures and modes, and the mid-span deflection versus time curves. Such good agreements verified the accuracy of the developed FE model to simulate the LSF floor panels made of HFS joists under fire conditions. Thermal FE models of LSF floor systems made of HFS joists were then developed and the time-temperature profiles were compared with the fire test results. They showed better agreements for Tests 1 and 4 whereas there were some discrepancies for Tests 2 and 3. Thermal FEA results obtained using appropriate thermal properties of plywood showed a reasonably good agreement with Baleshan's (2012) fire test results. Parametric studies using the validated model showed that joist section depth and profile had no significant impact on the thermal performance of LSF floor systems whereas steel joist thickness had a significant influence. An extensive FEA based parametric study was then undertaken to investigate the effects of joist thickness, depth, section profile, steel grade and mechanical property reduction factors, and web openings on the structural and fire performances (FRR) of LSF floor systems. Steel joist thickness significantly influenced the FRR of LSF floor systems due to different temperature developments in the steels for varying thicknesses. Joist section depth, section profile and web openings had no significant impact on the FRRs of LSF floor systems. Steel type affected the FRRs of LSF floor systems significantly due to different mechanical property reduction factors, especially different yield strength reduction factors. It was shown that Baleshan's (2012) critical average joist temperature method can be used to determine the FRR of non-insulated dual and single plasterboard lined floor panels made of HFS joists. However, it can be used for cavity insulated floor panels when the load ratio is less than 0.3. Fire test and FEA results showed that LSF floor panels made of LSB joists gave higher FRRs due to improved elevated temperature mechanical properties of LSB plate elements and lower temperature development due to thicker joists. Fire design rules were developed to predict the FRRs of LSF floor systems made of HFS joists based on Eurocode 3 Part 1.3 (ECS, 2006), AS/NZS 4600 (SA, 2005) and Direct Strength Method (DSM). For this purpose, Baleshan's (2012) three fire design rules of LCS joists were used and suitable modifications were made in order to use them for HFS joists. A good agreement was observed between the FRR predictions using two design methods and FEA, and thus they were recommended. In addition, the FRR predictions of HFS joists using the fire design method developed based on DSM were modestly conservative and therefore they were also recommended. Finally, the spread sheet based design tool was developed to undertake the complex calculations in predicting the FRR of LSF floors made of HFS joists with varying sizes and steel types, and subjected to varying load ratios. In summary, this research has significantly improved the knowledge and understanding of the fire performance of LSF floor systems made of hollow flange section joists and developed accurate fire design rules. Structural and fire design engineers can use the developed spread sheet based design tool to predict the fire performance of LSF floor systems made of HFS joists with varying sizes and steel types for a range of applications in commercial and residential buildings.
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50

Pan, Li. "Limit load estimation for structures under mechanical loads /." 2003.

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