Current procedures for estimating effective length factors for web-tapered members rely heavily on the use of charts and graphs. This makes them difficult to implement using a computer. In addition, they are often based on unrealistic assumptions. In cases where these assumptions are not satisfied, design errors may result. This investigation proposes a modification to an effective length factor expression developed by Lui (1992). This modification allows the expression to be applied to web-tapered members with good accuracy. A derivation of the proposed expression is presented, and the results obtained by applying the expression to a range of frames are compared to the results obtained from second-order finite element analyses. Calculations involved in using the expression are presented. / Master of Science

The design of metal building roof and wall systems under uplift and suction wind loading is complicated because the laterally unbraced purlin and girt's free flange is compressed, and the cross-section rotates due to the shear flow. The objective of this thesis is to introduce a Direct Strength Method (DSM) prediction approach for simple span purlins and girts with one flange through-fastened under uplift or suction loading. This prediction method is also applicable for the case when rigid board insulation is placed between the metal panel and through-fastened flange. The prediction method is validated with a database of 62 simple span tests. To evaluate the prediction for the case when rigid board is used, 50 full-scale tests with rigid board insulation are conducted by the author of this thesis. In the experimental study panel failure, connection failure and member (purlin and girt) failure are observed, and they all limit the system's capacity. Another important contribution of this thesis is that it builds the foundation for future study of a general, mechanics-based limit state design approach for metal building roof and wall systems that can accommodate uplift and gravity loads, simple and continuous spans, and through-fastened and standing seam roofs. / Ph. D.

An experimental investigation was conducted to study the extended end-plate moment connections subjected to cyclic loading. Seven specimens representing three end-plate moment connection configurations commonly used in the pre-engineered building industry were used. The connections were designed using yield-line theory to predict end-plate yielding and the modified Kennedy method to predict maximum bolt force calculations including prying action. A displacement controlled loading history was used to load the specimens. The maximum moments obtained experimentally and the experimental bolt forces throughout loading were compared with analytical predictions and finite element model results. The inelastic rotation of connections was calculated and conclusions were drawn on the compliance of these connections with current AISC specifications. / Master of Science

This study examined the effects of the presence of fungal growth on the phthalate ester content of plasticized polyvinyl chloride (pPVC) used as the vapor barrier component of metal building insulation and the impact the fungal growth may have on the resulting exposure potential to the workers in the building. Individual pieces of the pPVC material exhibiting fungal growth and individual pieces of the pPVC material exhibiting no fungal growth were collected from the building being investigated. Twenty-five pieces each of the pPVC material exhibiting fungal growth and of the pPVC material exhibiting no fungal growth were weighed, reduced to small pieces, and extracted with dichloromethane. The extracts were analyzed using a gas chromatograph coupled with a mass spectrometer. The phthalate content of four phthalate esters identified in the pPVC: diethyl phthalate (DEP), dibutyl phthalate (DBP), butyl benzyl phthalate (BBP), and di-(2-ethylhexyl) phthalate (DEHP), was quantified and the results extrapolated to concentration based on weight ([um]g/Kg) and area ([um]g/m2). A paired samples t test and independent samples t test was used to identify where significant differences occurred (α = 0.05) in the phthalate content between pieces. Using the mean concentration for each phthalate ester, a worst-case-scenario exposure was modeled. There was a statistically significant difference in the phthalate ester content between the pPVC exhibiting fungal growth and pPVC exhibiting no fungal growth for all four phthalate esters investigated. The mean phthalate ester concentration ranged from 13.74 [um]g/m2-34.94 [um]g/m2 in the pPVC exhibiting no fungal growth and 12.00 [um]g/m2-30.63 [um]g/m2 in the pPVC exhibiting fungal growth. The modeled exposure concentration in the building ranged from 0.39 [um]g/m3-0.98 [um]g/m3 and was generally lower than published exposure concentrations in similar settings.

Prediction of the clip reactions of a standing seam roof in a metal building under dynamic loading is of great interest because currently static uplift tests are the standard for determining the design load capacity. The use of a static test to replicate a dynamic loading leads to a great amount of debate because clearly a standing seam roof visually behaves very different under the two different types of loads. This leads to the question of whether a static test accurately replicates the magnitude of loads that the roof clips would feel under a dynamic wind load. This study uses a magnetic suspension uplift loading for the simulation of wind tunnel data in comparison with the ASTM E-1592 ?Standard Test Method for Structural Performance of Sheet Metal Roof and Siding Systems by Uniform Static Air Pressure Difference? test to determine clip reactions. An approximate finite element model is also utilized to verify the validity of the experimentally acquired clip reactions to form another comparison.

Z-sections are widely used as secondary members in metal building roof systems. Lateral restraints are required to maintain the stability of a Z-section roof system and provide resistance to the lateral forces generated by the slope of the roof and the effects due to the rotation of the principal axes of the Z-section relative to the plane of the roof sheathing. The behavior of Z-sections in roof systems is complex as they act in conjunction with the roof sheathing as a system and as a light gage cold formed member, is subject to local cross section deformations. The goal of this research program was to provide a means of predicting lateral restraint forces in Z-section supported roof systems. The research program began with laboratory tests to measure lateral restraint forces in single and multiple span sloped roof systems. A description of the test apparatus and procedure as well as the results of the 40 tests performed is provided in Appendix II. To better understand the need for lateral restraints and to provide a means of testing different variables of the roof system, two types of finite element models were developed and are discussed in detail in appended Paper I. The first finite element model is simplified model that uses frame stiffness elements to represent the purlin and sheathing. This model has been used extensively by previous researchers and modifications were made to improve correlation with test results. The second model is more rigorous and uses shell finite elements to represent the Z-section and sheathing. The shell finite element model was used to develop a calculation procedure referred to as the Component Stiffness Method for predicting the lateral restraint forces in Z-section roof systems. The method uses flexural and torsional mechanics to describe the behavior of the Z-section subject to uniform gravity loads. The forces generated by the system of Z-sections are resisted by the "components" of the system: the lateral restraints, the sheathing and Z-section-to-rafter connection. The mechanics of purlin behavior providing the basis for this method are discussed in appended Paper II. The development of the method and the application of the method to supports restraints and interior restraints are provided in appended papers III, IV and V. / Ph. D.