Design Of Perforated Industrial Storage Rack Columns For Distortional Buckling,
2012
Missouri University of Science and Technology
Design Of Perforated Industrial Storage Rack Columns For Distortional Buckling, Teoman Peköz, Güven Kıymaz, Miquel Casafont, Maria Magdalena Pastor, Jordi Bonada
CCFSS Proceedings of International Specialty Conference on Cold-Formed Steel Structures (1971 - 2018)
The results of an on-going research program to develop a design procedure for perforated industrial storage rack columns are presented. The design procedure includes the effects of distortional buckling. The types of columns studied include those commonly used in Europe and some that are used in the US. The design procedure is being developed based on finite element studies verified by physical testing. The design procedure involves the use of the current US rack column design approach with an extension to distortional buckling with Finite Strip Method (FSM) solutions and Direct Strength Method (DSM) approaches. The approach originally developed for …
Advanced Design Optimization Of Cold-Formed Steel Portal Frame Buildings,
2012
Missouri University of Science and Technology
Advanced Design Optimization Of Cold-Formed Steel Portal Frame Buildings, Duoc T. Phan, James B. P. Lim, Tiku T. Tanyimboh, Wei Sha
CCFSS Proceedings of International Specialty Conference on Cold-Formed Steel Structures (1971 - 2018)
The design optimization of cold-formed steel portal frame buildings is considered in this paper. The objective function is based on the cost of the members for the main frame and secondary members (i.e., purlins, girts, and cladding for walls and roofs) per unit area on the plan of the building. A realcoded niching genetic algorithm is used to minimize the cost of the frame and secondary members that are designed on the basis of ultimate limit state. It is shown that the proposed algorithm shows effective and robust capacity in generating the optimal solution, owing to the population’s diversity being …
An Efficient Genetic Algorithm For The Design Optimization Of Cold-Formed Steel Portal Frame Buildings,
2012
Missouri University of Science and Technology
An Efficient Genetic Algorithm For The Design Optimization Of Cold-Formed Steel Portal Frame Buildings, Duoc T. Phan, James B. P. Lim, Tiku T. Tanyimboh, Wei Sha
CCFSS Proceedings of International Specialty Conference on Cold-Formed Steel Structures (1971 - 2018)
The design optimization of cold-formed steel portal frame buildings is considered in this paper. The real-coded genetic algorithm (GA) optimizer proposed considers both building’s topology (i.e. frame spacing and pitch) and cross-sectional sizes of the main structural members as the decision variables that are optimized. Previous GAs in the literature were characterized by poor convergence including slow progress that usually results in excessive computation times and/or frequent failure to achieve an optimal or near-optimal solution. This is the main issue addressed in this paper. In an effort to improve the performance of the conventional GA, a niching strategy is presented …
Prediction Of Joint Temperatures In Shot-Nailed Cold-Formed Steel Sheeting With Finite Element Modelling,
2012
Missouri University of Science and Technology
Prediction Of Joint Temperatures In Shot-Nailed Cold-Formed Steel Sheeting With Finite Element Modelling, Z. Ma, W. Lu, P. Mäkeläinen, J. Outinen
CCFSS Proceedings of International Specialty Conference on Cold-Formed Steel Structures (1971 - 2018)
This paper investigates the 3D temperature fields of the shot-nailed steel roof sheeting joints in fire using commercial Finite Element (FE) software ABAQUS when the connected members and connections are protected by either intumescent paint or rockwool panels. Numerical models and parameters used in the models are briefly introduced. When expanded in fire, both thickness and thermal conductivity are varied with increased temperatures. The simplified representation of intumescent paint is described. Parametric analyses are performed in order to investigate the sensitivity of the parameters of thermal contacts. When the joints are protected with rockwool panels, the approximate cavity radiation method …
Studies On Bracing Member End Connections For Cold Formed Steel Sections,
2012
Missouri University of Science and Technology
Studies On Bracing Member End Connections For Cold Formed Steel Sections, R. P. Rokade, N. Prasad Rao, R. Balagopal, S. J. Mohan
CCFSS Proceedings of International Specialty Conference on Cold-Formed Steel Structures (1971 - 2018)
This paper is concentrated mainly on the behaviour of bracing end connections for cold formed steel lipped angle and lipped channel sections. For bracing members, only one flange is possible to connect with tower leg member or supporting member, which causes uneven distribution of stresses in the end section popularly known as shear lag effect. Tension tests have been carried out to simulate the bracing end connections. Special test rig has been assembled and end fittings fabricated such that the load will be applied as concentric load at the pulling end and on the other end load is transferred through …
Using Generalized Beam Theory (Gbt) To Assess The Buckling Behavior Of Cold-Formed Steel Structural Systems,
2012
Missouri University of Science and Technology
Using Generalized Beam Theory (Gbt) To Assess The Buckling Behavior Of Cold-Formed Steel Structural Systems, Cilmar Basaglia, Dinar Camotim
CCFSS Proceedings of International Specialty Conference on Cold-Formed Steel Structures (1971 - 2018)
This paper deals with the application of beam finite element models based on Generalized Beam Theory (GBT) to analyze the buckling behavior of three cold-formed steel structural systems, namely (i) beams belonging to storage rack systems, (ii) portal frames built from rectangular hollow section (RHS) profiles and (iii) roof-supporting trusses, exhibiting different support conditions and subjected to various loadings. In particular, taking advantage of the GBT unique and structurally clarifying modal features, it is possible to assess how different geometries and/or bracing arrangements affect (improve) the local, distortional and/or global buckling behavior of the above structural systems. The accuracy of …
Permanent Stability Bracing Of Cfs Trusses,
2012
Missouri University of Science and Technology
Permanent Stability Bracing Of Cfs Trusses, Sowri Rajan, William L. Babich
CCFSS Proceedings of International Specialty Conference on Cold-Formed Steel Structures (1971 - 2018)
Permanent stability bracing of Cold-Formed Steel (CFS) roof/floor trusses is needed for the three major planes in a truss: Top chord, Bottom Chord and Web. Primary function of bracing is to prevent lateral instability of members as well as stiffen the overall roof/floor system. Brace force is dependent on the magnitude of applied loads and the level of out-of-planeness permitted. Traditionally, 2% of the axial compression force in a member is used as the brace (restraint) force, which is based on an out-of-plane deflection of L/200 where L is the member length. Continuous Lateral Restraint (CLR) forces are accumulated from …
Investigation Of Behavior Of Cold-Formed Steel Sheeting Systems In Fire Using Finite Element Modeling,
2012
Missouri University of Science and Technology
Investigation Of Behavior Of Cold-Formed Steel Sheeting Systems In Fire Using Finite Element Modeling, W. Lu, P. Mäkeläinen, J. Outinen, Z. Ma
CCFSS Proceedings of International Specialty Conference on Cold-Formed Steel Structures (1971 - 2018)
A 3D Finite Element (FE) model of steel sheeting, which includes the screw connector and support plate, is created to investigate the behavior of both steel sheeting and connections at elevated temperatures. The created model considers the material nonlinearity, large deformation and contact behavior. The material damage model for sheeting steel is defined so that the FE model is analyzed through the elastic and plastic ranges up to failure. The FE model is used to predict the ultimate resistance and deformation. The current FE model captures the main behavior of steel roof systems well up to around 20 minutes according …
Steel Cold-Formed Trussed Girders With Joint Eccentricities - Improvements On Design And Performance By Numerical And Experimental Analysis,
2012
Missouri University of Science and Technology
Steel Cold-Formed Trussed Girders With Joint Eccentricities - Improvements On Design And Performance By Numerical And Experimental Analysis, Eduardo De M. Batista, Alexandre Landesmann, Juarez M. Franco
CCFSS Proceedings of International Specialty Conference on Cold-Formed Steel Structures (1971 - 2018)
Long span light roof systems of industrial buildings are frequently designed with cold-formed steel members, leading to competitive solution which allows liberating useful internal space inside the building. This type of structural solution is usually cost saving if it is combined with standardization of the manufacturing process thus enabling specialized solution. This is the case of a family of trussed girders ranging from 0.6 to 1.8 m depth, developed by the steel structures manufacturer and addressed to a standard system for general application enabling to bridge up to 40 m span of light roof construction. Typical buckling behavior of the …
Novel Cold-Formed Steel Elements For Seismic Applications,
2012
Missouri University of Science and Technology
Novel Cold-Formed Steel Elements For Seismic Applications, Alireza Bagheri Sabbagh, Mihail Petkovski, Kypros Pilakoutas, Rasoul Mirghaderi
CCFSS Proceedings of International Specialty Conference on Cold-Formed Steel Structures (1971 - 2018)
Novel cold-formed steel (CFS) elements are investigated in this paper for seismic resistant multi-storey moment frames. Premature local buckling and low out-of-plane stiffness are known as the main structural deficiencies of CFS sections with thin-walled elements. These lead to low energy dissipation capacity of the structures made up of CFS sections as the main load bearing members in seismic events. In order to improve the energy dissipation capacity of CFS members, an innovative CFS beam section with curved flanges is developed by numerical FE analysis and experimental work. A web bolted through plate CFS beam-column connection is used to limit …
Slip Modulus Of Cold-Formed Steel Members Sheathed With Wood Structural Panels,
2012
Missouri University of Science and Technology
Slip Modulus Of Cold-Formed Steel Members Sheathed With Wood Structural Panels, A. L. Northcutt, K. W. Kramer, S. F. Stephens
CCFSS Proceedings of International Specialty Conference on Cold-Formed Steel Structures (1971 - 2018)
Cold-formed steel framing sheathed with wood structural panels is a common method of construction for wall, roof and floor systems in cold-formed steel structures. Since wood structural panels are attached with screws at relatively close spacing, a certain amount of composite behavior will be present. The benefit of composite behavior is not currently being taken advantage of in the design of these structural systems. While composite effects are present, they are not yet being accounted for in design due to a lack of statistical data. To determine the amount of composite action taking place in these systems, the slip modulus …
Seismic Computational Analysis Of Cfs-Nees Building,
2012
Missouri University of Science and Technology
Seismic Computational Analysis Of Cfs-Nees Building, J. Leng, B. W. Schafer, S. G. Buonopane
CCFSS Proceedings of International Specialty Conference on Cold-Formed Steel Structures (1971 - 2018)
The objective of this paper is to explore computational modeling of a coldformed steel framed building subjected to earthquake excitation. The selected two-story building will be subjected to full-scale motion on a shaking table in 2013 as part of the National Science Foundation funded Cold-Formed Steel – Network for Earthquake Engineering Simulation (CFS-NEES) project. The ledger-framed building employs load bearing cold-formed steel members throughout (wall, floors, and roofs) and employs OSB sheathed shear walls and an OSB sheathed diaphragm for the lateral force resisting system. Two- and three-dimensional analysis models capable of providing vibration, pushover, linear and nonlinear time history …
Characterizaiton Of Cold-Formed Steel Shear Wall Behavior Under Cyclic Loading For The Cfs-Nees Building,
2012
Missouri University of Science and Technology
Characterizaiton Of Cold-Formed Steel Shear Wall Behavior Under Cyclic Loading For The Cfs-Nees Building, P. Liu, K. D. Peterman, C. Yu, B. W. Schafer
CCFSS Proceedings of International Specialty Conference on Cold-Formed Steel Structures (1971 - 2018)
The objective of this paper is to provide a full hysteretic characterization of OSB sheathed cold-formed steel (CFS) shear walls designed for use in the National Science Foundation funded Network for Earthquake Engineering Simulation (NEES) project: CFS-NEES (www.ce.jhu.edu/cfsnees). The shear walls were designed for a two-story ledger-framed building (i.e., the CFS-NEES building) that will undergo full-scale shake table testing at the University of Buffalo NEES site. Shear walls in real construction, such as the CFS-NEES building, have details that differ from the shear walls tested and provided for strength prediction in standards such as AISI-S213-07. Differences include: (a) ledger (rim …
Network- Level Pavement Performance And Management Study In Connecticut,
2012
University of Connecticut
Network- Level Pavement Performance And Management Study In Connecticut, Ramandeep S. Josen
Master's Theses
This thesis presents the analysis of asphalt pavement cracking data on the network level in Connecticut. Pavement performance indicators including longitudinal and transverse cracking as well as roughness are investigated with respect to numerous distinct factors that can be grouped into three categories, i.e. climatic-, pavement structure-, and traffic-related. High-quality climatic data was obtained from the national weather stations in Connecticut. Maintenance and construction data was used to determine the pavement age and structure amongst several other factors. Traffic data was acquired from the state records and accumulated traffic loading was estimated for all segments based on their age. High …
Using Nwp Analysis In Satellite Rainfall Estimation Of Heavy Precipitation Events Over Complex Terrain,
2012
University of Connecticut
Using Nwp Analysis In Satellite Rainfall Estimation Of Heavy Precipitation Events Over Complex Terrain, Xinxuan Zhang
Master's Theses
This study investigates the use of Weather Research and Forecasting (WRF) high-resolution storm analysis in satellite rainfall estimation over complex terrains. Rainfall estimation here is based on the NOAA-Climate Prediction Center morphing (CMORPH) product. Specifically, CMORPH rainfall is adjusted by applying a power-law function whose parameter values are obtained from the comparison between WRF and CMORPH hourly rain rates. Results are presented based on the analyses of five storm cases that induced catastrophic floods in southern Europe. The WRF-based adjusted CMORPH rain rates exhibited improved error statistics against independent radar-rainfall estimates. We show that the adjustment reduces the underestimation of …
The Effects Of Bolt Pretension, In-Plane Eccentricity, And Friction On The Ductility Of Block Shear Connections,
2012
University of Connecticut
The Effects Of Bolt Pretension, In-Plane Eccentricity, And Friction On The Ductility Of Block Shear Connections, Kevin M. Zmetra
Master's Theses
Block shear is a complex failure mechanism in bolted and welded steel components such as gusset plates, webs of coped beams, angles and tees. It presumes a combination of tension rupture and shear yield. Multiple variables affect the block shear capacity and ductility of a connection. This study investigates the effects of bolt pretension, connection eccentricity and friction force transfer through a series of destructive experiments followed by refined finite element simulation. Clamping forces create a complex triaxial stress field compounded by the stress concentration at the bolt holes. In-plane load eccentricity with respect to the centerline of the connection …
Modal Identification Of Cold-Formed Steel Members In Shell Finite Element Models,
2012
Missouri University of Science and Technology
Modal Identification Of Cold-Formed Steel Members In Shell Finite Element Models, Z. Li, S. Ádány, B. W. Schafer
CCFSS Proceedings of International Specialty Conference on Cold-Formed Steel Structures (1971 - 2018)
This paper illustrates new capabilities for modal identification of shell Finite Element Method (FEM) models of thin-walled cold-formed steel members. The separation of general deformations into fundamental buckling deformation classes: local, distortional, global, shear, and transverse extension, originated with the constrained Finite Strip Method (cFSM) and is extended here to shell element based FEM analysis. The cFSM base vectors for general end boundary conditions, previously developed by the authors, provide a series of general base functions capable of separating displacements into classes. FEM displacements are identified by minimizing error between the actual FEM displacements and those predicted by the cFSM …
Experimental Study On Interaction Between Local And Distortional Buckling Of High Strength Cold-Formed Lipped Channel Columns,
2012
Missouri University of Science and Technology
Experimental Study On Interaction Between Local And Distortional Buckling Of High Strength Cold-Formed Lipped Channel Columns, L. Jiang, B. K. He, Y. Q. Li
CCFSS Proceedings of International Specialty Conference on Cold-Formed Steel Structures (1971 - 2018)
The distortional buckling behavior of 550MPa high strength cold-formed lipped channel columns under axial compression loads have been studied. The test results of 16 specimens show that local buckling may appear before distortional buckling and it makes the distortional buckling occur in advance. This interaction of local and distortional buckling has an adverse effect on bearing capacity of columns. But the design methods for distortional buckling in Specification AS/NZS 4600 and Direct Strength Method (DSM) haven’t considered such interaction. Based on the test results, a method revised from DSM which could account for the adverse interaction has been suggested. The …
Cold-Forming Effect Investigation On Cold-Formed Thick-Walled Steel Hollow Sections,
2012
Missouri University of Science and Technology
Cold-Forming Effect Investigation On Cold-Formed Thick-Walled Steel Hollow Sections, Y. Q. Li, D. H. Wen, L. P. Wang, Z. Y. Shen
CCFSS Proceedings of International Specialty Conference on Cold-Formed Steel Structures (1971 - 2018)
No abstract provided.
Analytical Model For Cold-Formed Steel Framed Shear Wall With Steel Sheet Sheathing,
2012
Missouri University of Science and Technology
Analytical Model For Cold-Formed Steel Framed Shear Wall With Steel Sheet Sheathing, Noritsugu Yanagi, Cheng Yu
CCFSS Proceedings of International Specialty Conference on Cold-Formed Steel Structures (1971 - 2018)
The cold-formed steel framed shear wall sheathed with steel sheet sheathing (CFS-SSSW) is a code approved lateral force resisting system for light framed construction. The AISI Steel Framing Standards – Lateral Design (AISI S213-07) provides design provisions for CFS-SSSW. The development of the nominal strength of CFS-SSSW in AISI S213 was based on full-scale experiments which were subjected to limitations in both wall configurations and material properties. This paper presents an analytical model – the Effective Strip Model developed for predicting the nominal strength of CFS-SSSWs. The proposed analytical model and supporting design equations are further verified by experimental results. …
