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2018

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Articles 61 - 90 of 224

Full-Text Articles in Structural Engineering

Parametric Studies And Design Recommendations Of Cold-Formed Steel Sections With Edge-Stiffened Circular Holes Subjected To Web Crippling, Asraf Uzzaman, James B. P. Lim, David Nash, Amir M. Yousefi, Benjamin Young Nov 2018

Parametric Studies And Design Recommendations Of Cold-Formed Steel Sections With Edge-Stiffened Circular Holes Subjected To Web Crippling, Asraf Uzzaman, James B. P. Lim, David Nash, Amir M. Yousefi, Benjamin Young

CCFSS Proceedings of International Specialty Conference on Cold-Formed Steel Structures (1971 - 2018)

A parametric study of cold-formed steel sections with edge-stiffened circular holes subjected to web crippling under one-flange loading condition was undertaken using finite element analysis. The effect of different hole sizes, edge-stiffener length and distances of the web holes to the near edge of the bearing plate on the web crippling strengths of channel sections were investigated. The web crippling strengths are influenced by various geometry parameters: the ratio of the hole depth to the flat portion of the web, a/h, the location of the hole as defined by the distance of the hole from the edge of the …


A Preliminary Study On Stainless Steel Hollow Flange Beams Featuring Lateral-Distortional Buckling, Shuang Niu, Zhidong Zhang, Feng Fan Nov 2018

A Preliminary Study On Stainless Steel Hollow Flange Beams Featuring Lateral-Distortional Buckling, Shuang Niu, Zhidong Zhang, Feng Fan

CCFSS Proceedings of International Specialty Conference on Cold-Formed Steel Structures (1971 - 2018)

To explore the potential of using stainless steel structurally, extensive research has been carried out to study the structural behavior of stainless steel member as associated with the nonlinear stress-strain relationship. Hollow flange sections feature improved structural efficiency and a unique issue of web distortion. Steel hollow flange sections have been studied and commercially distributed (e.g. the very first HFB section and lately LSB section). As a proactive study, this paper investigates stainless steel hollow flange beams of double-symmetric section with numerical modeling and parametric analysis. The validity of the idealized FE model was verified with existing study on steel …


Study On Distortional Buckling Of Cold-Formed Stainless Steel Beams, Shuang Niu, Zhidong Zhang, Feng Fan Nov 2018

Study On Distortional Buckling Of Cold-Formed Stainless Steel Beams, Shuang Niu, Zhidong Zhang, Feng Fan

CCFSS Proceedings of International Specialty Conference on Cold-Formed Steel Structures (1971 - 2018)

In the current research, distortional buckling of cold-formed stainless steel open-section beams was investigated. Four-point bending tests of eight C-section stainless steel beams, made of S30401 alloy, were carried out with global and local buckling precluded by careful design of specimen and test rigs. A detailed finite element model based on ABAQUS was developed and verified against test data. Parametric study was carried out with the verified model, covering four types of sections (C, Z, SupaCee, and SupaZed), three stainless steel alloys (S30401, S44330, S32101), and a series of section slenderness. A convenient method to identify distortional buckling point in …


Flexural Strength Of Continuous-Span Z-Purlins With Paired Torsion Braces Using The Direct Strength Method, Michael Seek Nov 2018

Flexural Strength Of Continuous-Span Z-Purlins With Paired Torsion Braces Using The Direct Strength Method, Michael Seek

CCFSS Proceedings of International Specialty Conference on Cold-Formed Steel Structures (1971 - 2018)

A procedure is presented to calculate the local and distortional flexural buckling strength of continuous span purlins with paired torsion braces using the Direct Strength Method. Displacement compatibility is utilized to determine the forces interacting between the purlin, the flexible diaphragm and the torsion braces. The biaxial bending and torsion effects caused by this interaction are superimposed, and the actual distribution of stresses within the cross section are calculated at critical locations along the span. With this distribution of stresses, a finite strip buckling analysis is performed to determine the local and distortional buckling strength. In current design practice, results …


Bracing Design For Torsional Bucking Of Cold-Formed Steel Wall Stud Columns, C. D. Moen Nov 2018

Bracing Design For Torsional Bucking Of Cold-Formed Steel Wall Stud Columns, C. D. Moen

CCFSS Proceedings of International Specialty Conference on Cold-Formed Steel Structures (1971 - 2018)

A method is presented for calculating the required brace stiffness and strength to limit torsional buckling deformation in cold-formed steel wall stud columns. The bracing (bridging) design method utilizes recent insight from classical stability solutions that define twist of singly and doubly-symmetric columns with an initial twist imperfection as a function of column compressive load. A wall stud design example is provided.


Behavior Of Beam To Column Cold-Formed Section Connections Subjected To Bending Moments, Maged T. Hanna, Mohamed M. El-Saadawy, Ghada M. El-Mahdy, Ehab H. A. H. Aly Nov 2018

Behavior Of Beam To Column Cold-Formed Section Connections Subjected To Bending Moments, Maged T. Hanna, Mohamed M. El-Saadawy, Ghada M. El-Mahdy, Ehab H. A. H. Aly

CCFSS Proceedings of International Specialty Conference on Cold-Formed Steel Structures (1971 - 2018)

Cold formed sections are often used in the construction of mid-rise buildings due to their high strength weight ratios, and fast erection. In these buildings, the connections between joists and studs are mainly simple connections. However, application of these sections can be extended to moderate span frames where connections between members are subjected to bending moments. Strength and stability of such frames depends to large extent on the behaviour of the connections between their members. Over the last twenty years, several researchers undertake tests on cold formed section connections subjected to bending moments. Major of them classify the connections as …


Bearing Strength Of Untightened Double-Shear Bolted Connections In Cold-Formed Steel Construction, Refat Bhuiyan, Lip H. Teh Nov 2018

Bearing Strength Of Untightened Double-Shear Bolted Connections In Cold-Formed Steel Construction, Refat Bhuiyan, Lip H. Teh

CCFSS Proceedings of International Specialty Conference on Cold-Formed Steel Structures (1971 - 2018)

This paper presents the experimental investigation of cold-formed steel double-shear bolted connections where both the bolt head and the nut are not in contact with the outer sheets. The inner sheet of each specimen is not constrained from out-of-plane distortion or bulging downstream of the bolt, and fails in bearing. Based on a series of tests involving specimens having bolt diameters ranging from 12 to 16 mm and sheet thicknesses ranging from 1.5 to 3.0 mm, it has been found that the absence of out-of-plane constraint in untightened bolted connections leads to much lower bearing capacities than predicted by the …


Cold-Formed Steel Bolted Moment-Resisting Connections With Friction-Slip Mechanism For Seismic Areas, Marzie Shahini, Alireza Bagheri Sabbagh Nov 2018

Cold-Formed Steel Bolted Moment-Resisting Connections With Friction-Slip Mechanism For Seismic Areas, Marzie Shahini, Alireza Bagheri Sabbagh

CCFSS Proceedings of International Specialty Conference on Cold-Formed Steel Structures (1971 - 2018)

This paper presents investigation on cold-formed steel (CFS) beam-to-column moment-resisting (MR) bolted connections with high energy dissipation capacity suitable for seismic areas. Bolting friction-slip mechanism of the introduced CFS MR connection is developed as its main seismic energy dissipation fuse aiming to postpone or eliminate local buckling and yielding in the CFS MR connections. Finite Element (FE) modelling techniques are employed to effectively simulate the connections with an activated friction-slip mechanism. Hysteretic energy dissipation response of the connections with circular bolting (CB) arrangement designed to slip at 0.5Mp are presented. Based on the obtained FE results, full-scale physical tests on …


Planning The Future Of North American Cold-Formed Steel Design Standards, Benjamin W. Schafer, Jay Larson, Helen Chen Nov 2018

Planning The Future Of North American Cold-Formed Steel Design Standards, Benjamin W. Schafer, Jay Larson, Helen Chen

CCFSS Proceedings of International Specialty Conference on Cold-Formed Steel Structures (1971 - 2018)

Growth in cold-formed steel structures has long been tied to developing and advancing the engineering standards that govern their use in construction. The American Iron and Steel Institute (AISI) has taken a leadership role in this activity in North America since 1946. Conventional standards providing closed-formed solutions to member capacity, such as the recently completed suite of AISI Standards in 2015 and 2016. These standards have reached an impressive level of maturity given the complexity of designing entire (building) structural systems out of steel that is rarely greater than 2mm thick. However, the demands on the structural engineer designing cold-formed …


Biaxial Bending Of Cold-Formed Steel Storage Rack Uprights – Part I: Parametric Studies And Response, Nima Talebian, Benoit P. Gilbert, Cao Hung Pham, Romain Chariere, Hassan Karampour Nov 2018

Biaxial Bending Of Cold-Formed Steel Storage Rack Uprights – Part I: Parametric Studies And Response, Nima Talebian, Benoit P. Gilbert, Cao Hung Pham, Romain Chariere, Hassan Karampour

CCFSS Proceedings of International Specialty Conference on Cold-Formed Steel Structures (1971 - 2018)

This paper first introduces an advanced finite element model to determine the biaxial bending capacity of cold-formed steel storage rack upright sections. The model is found to accurately predict published experimental results with an average predicted to experimental capacity ratio of 1.02. Second, the validated model is used to run parametric studies and analyse the biaxial response of slender, semi-compact and compact unperforated storage rack upright cross-sections. Analyses are run for local and distortional buckling failure modes only. Ten and four different cross-sectional shapes are analysed for local and distortional buckling, respectively, and nine biaxial bending configurations are considered per …


Biaxial Bending Of Cold-Formed Steel Storage Rack Uprights – Part Ii: Design Methods, Nima Talebian, Benoit P. Gilbert, Cao Hung Pham, Hassan Karampour Nov 2018

Biaxial Bending Of Cold-Formed Steel Storage Rack Uprights – Part Ii: Design Methods, Nima Talebian, Benoit P. Gilbert, Cao Hung Pham, Hassan Karampour

CCFSS Proceedings of International Specialty Conference on Cold-Formed Steel Structures (1971 - 2018)

This paper uses the results from the parametric studies reported in the companion paper to verify the accuracy of different forms of published direct strength method (DSM) equations. They consist of the classical DSM equations and considering the inelastic reserve capacity into these equations, with and without an extended range of the cross-sectional slenderness. The verifications are made for local and distortional buckling modes. Results show that for all investigated buckling modes, the DSM results in better predictions when the inelastic reserve capacity is considered. The appropriate form of the DSM to predict the biaxial capacity of unperforated cold-formed steel …


Behavior Of Cold-Formed Steel Metal Industrial Buildings, Adrianna M. Early, M. Ebrahim Mohammadi, Richard L. Wood, Kara D. Peterman Nov 2018

Behavior Of Cold-Formed Steel Metal Industrial Buildings, Adrianna M. Early, M. Ebrahim Mohammadi, Richard L. Wood, Kara D. Peterman

CCFSS Proceedings of International Specialty Conference on Cold-Formed Steel Structures (1971 - 2018)

This paper presents research focused on understanding the observed behavior of cold-formed steel (CFS) metal buildings during Hurricane Harvey, which made landfall Friday, August 25, 2017 between Port Aransas and Port O’Connor, Texas. Through the Geotechnical Extreme Event Reconnaissance (GEER) association (funded by the National Science Foundation) a team of structural engineers and researchers performed rapid and detailed assessments of structural damage caused by the hurricane. The National Science Foundation gathered photographs, damage assessments sheets, and three-dimensional laser point cloud data of severely damaged cold-formed steel industrial buildings. The Port Aransas County Airport experienced severe damage to several cold-formed steel …


Sustainability Of Modular Lightweight Steel Building From Design To Construction, Ornella Iuorio, Loredana Napolano, Luigi Fiorino, Raffaele Landolfo Nov 2018

Sustainability Of Modular Lightweight Steel Building From Design To Construction, Ornella Iuorio, Loredana Napolano, Luigi Fiorino, Raffaele Landolfo

CCFSS Proceedings of International Specialty Conference on Cold-Formed Steel Structures (1971 - 2018)

The increasing concerns over population growth, depletion of natural resources and global warming as well as catastrophic natural events is leading the international scientific community to envisage sustainability as a crucial goal. The built environment plays a key role on the triple bottom line of the sustainable development -- Planet, People, Profit -- because of several environmental, social and economic impacts produced by the construction sector. The acknowledged need to promote a sustainable building market is an international high-priority issue as underlined by the 2030 Agenda for Sustainable Development. Indeed one of its strategic objectives highlights to make cities and …


Influence Of Fire On The Shear Capacity Of Cold-Formed Steel Framed Shear Walls, M. S. Hoehler, B. Andres Nov 2018

Influence Of Fire On The Shear Capacity Of Cold-Formed Steel Framed Shear Walls, M. S. Hoehler, B. Andres

CCFSS Proceedings of International Specialty Conference on Cold-Formed Steel Structures (1971 - 2018)

This paper presents experimental investigations of the performance of common lateral force-resisting systems used in cold-formed steel construction under sequential thermal (fire) and mechanical (earthquake) loading. Wall specimens with gypsum-sheet steel composite sheathing, Oriented Strand Board (OSB) sheathing, or steel strap bracing were tested. The results demonstrate that the lateral capacity of wall systems can be reduced by exposure to fire. Additionally, fire performance of wall systems can be affected by pre-damage to the fire-resistive components that provide fire protection to these walls. The results are useful for fire compartmentation design when significant lateral deformation of a building is anticipated …


Cold-Formed Steel Framed Shear Wall Database, Deniz Ayhan, Samuel Baer, Zhidong Zhang, Colin A. Rogers, Benjamin W. Schafer Nov 2018

Cold-Formed Steel Framed Shear Wall Database, Deniz Ayhan, Samuel Baer, Zhidong Zhang, Colin A. Rogers, Benjamin W. Schafer

CCFSS Proceedings of International Specialty Conference on Cold-Formed Steel Structures (1971 - 2018)

The objective of this paper is to provide an introduction to a recently compiled database of cold-formed steel framed shear wall tests and demonstrate the application of this database for improving the understanding and modeling of cold-formed steel framed shear walls. Over the last 20 years a substantial number of cold-formed steel framed shear walls have been tested under monotonic and cyclic conditions. These tests provide the support for the cold-formed steel framed shear wall provisions provided in the North American Standard for Cold-Formed Steel Structural Framing (AISI S240-15), the North American Standard for Seismic Design of Cold-Formed Steel Structural …


Seismic Behavior Of Cold-Formed Steel Shear Walls During Full-Scale Building Shake Table Tests, X. Wang, Tara C. Hutchinson, G. Hegemier, Colin A. Rogers Nov 2018

Seismic Behavior Of Cold-Formed Steel Shear Walls During Full-Scale Building Shake Table Tests, X. Wang, Tara C. Hutchinson, G. Hegemier, Colin A. Rogers

CCFSS Proceedings of International Specialty Conference on Cold-Formed Steel Structures (1971 - 2018)

Cold-formed steel sheathed shear walls are now emerging as a strategic vertical lateral load resisting component in seismic design. However, although a number of component cyclic test programs have been conducted in recent years to characterize their hysteretic behavior and guide design, system-level test programs to investigate their performance are so far lacking in the literature. To this end, a unique full-scale CFS-framed mid-rise building shake table test program was conducted to contribute to understanding the behavior of mid-rise cold-formed steel (CFS) wall-braced buildings under a multi-hazard scenario. The centerpiece of this project involved earthquake and live fire testing of …


Performance Of Cold-Formed Steel Shear Walls With Frame Blocking And Double-Sheathing, Robert Rizk, Vincent Briere, Veronica Santos, Colin A. Rogers Nov 2018

Performance Of Cold-Formed Steel Shear Walls With Frame Blocking And Double-Sheathing, Robert Rizk, Vincent Briere, Veronica Santos, Colin A. Rogers

CCFSS Proceedings of International Specialty Conference on Cold-Formed Steel Structures (1971 - 2018)

This paper summarizes a laboratory based research program on blocked and double-sheathed cold-formed steel framed shear walls. The intent was to develop walls whose in-plane shear resistance exceeds that of configurations currently listed in the AISI S400 Standard. The results showed that the frame blocking can be used in the construction of walls whose resistance is at the limit of that found in AISI S400; however, the blocking will not adequately restrain the framing members if thicker sheathing is used. An approach was needed to minimize the effect of the eccentric loading caused by the sheathing and to account for …


Proposal To Improve The Dsm Design Of Cold-Formed Steel Angle Columns: Need, Background, Quality Assessment And Illustration, Pedro Borges Dinis, Dinar Camotim Nov 2018

Proposal To Improve The Dsm Design Of Cold-Formed Steel Angle Columns: Need, Background, Quality Assessment And Illustration, Pedro Borges Dinis, Dinar Camotim

CCFSS Proceedings of International Specialty Conference on Cold-Formed Steel Structures (1971 - 2018)

This paper presents a proposal for the codification of an efficient design approach, based on the Direct Strength Method (DSM), for cold-formed steel equal-leg angle columns with short-to-intermediate lengths, i.e., those buckling in flexural-torsional modes. Initially, the available experimental failure load data, comprising fixed-ended and pin-ended (“cylindrical hinges”) columns with several geometries (cross-section dimensions and lengths) and tested by various researchers, are collected and used to show that the currently codified DSM design provisions are not able to handle adequately short-to- intermediate angle columns and that a specific DSM-based design approach is needed to estimate the failure loads of such …


Distortional Buckling Of Cold-Formed Steel Flanges Under Stress Gradient, Robert S. Glauz Nov 2018

Distortional Buckling Of Cold-Formed Steel Flanges Under Stress Gradient, Robert S. Glauz

CCFSS Proceedings of International Specialty Conference on Cold-Formed Steel Structures (1971 - 2018)

The strength of cold-formed steel beams with stiffened flanges may be controlled by distortional buckling. Buckling stress prediction methods have been developed for flanges under uniform compression. However, channel sections are commonly used where bending occurs about the minor axis with flanges under stress gradient, such that the edges are in compression and the flanges may experience distortional buckling. Current design specifications do not explicitly address this failure mode, which could lead to unsafe designs. This paper presents and verifies an analytical approach for distortional buckling stress prediction for flanges under stress gradient. The approach is consistent with the design …


The Design And Development Of Lightweight Composite Panels For Rigid Wall Structures, Jeremy J. Artman, Cheng Yu Nov 2018

The Design And Development Of Lightweight Composite Panels For Rigid Wall Structures, Jeremy J. Artman, Cheng Yu

CCFSS Proceedings of International Specialty Conference on Cold-Formed Steel Structures (1971 - 2018)

The paper presents a research effort aimed at developing a stronger, lighter, and more economic shelter for both military and civilian use. Reported herein are the research results on developing solid wall panels using cold-formed steel corrugated sheathing and members, as well as polyurethane spray foam for insulation. This research includes calculating uniform load density, determining the overall strength of the panel, and investigating the flexural strength of the roof panels. Research incorporated different connection methods, with varied stud spacing, to determine the safest design for the new mobile facilities. Previous research has shown that cold-formed steel corrugated sheathing performs …


Web Crippling Behavior Of Cold-Formed Ferritic Stainless Steel Unlipped Channels Under Interior-One-Flange And End-One-Flange Loadings, Amir M. Yousefi, James B. P. Lim, G. Charles Clifton Nov 2018

Web Crippling Behavior Of Cold-Formed Ferritic Stainless Steel Unlipped Channels Under Interior-One-Flange And End-One-Flange Loadings, Amir M. Yousefi, James B. P. Lim, G. Charles Clifton

CCFSS Proceedings of International Specialty Conference on Cold-Formed Steel Structures (1971 - 2018)

The web crippling strength of cold-formed ferritic stainless steel unlipped channels subject to interior-one-flange and end-one-flange loading is considered in this paper. A total of 144 results are presented, comprising 36 laboratory and 108 numerical results. These results cover the cases of both flanges restrained and unrestrained to the load and reaction plates. Unlike other work in the literature, the numerical analysis in this paper uses nonlinear quasi-static finite element analysis with an implicit integration scheme, which has advantages over static and quasi-static with an explicit integration scheme analyses, particularly for post buckling predictions of unlipped channels subject to web …


Experimental And Analytical Studies Of Cold-Formed Steel Sections With Edge-Stiffened Circular Holes Subjected To Web Crippling, Asraf Uzzaman, James B. P. Lim, David Nash, Amir M. Yousefi, Benjamin Young Nov 2018

Experimental And Analytical Studies Of Cold-Formed Steel Sections With Edge-Stiffened Circular Holes Subjected To Web Crippling, Asraf Uzzaman, James B. P. Lim, David Nash, Amir M. Yousefi, Benjamin Young

CCFSS Proceedings of International Specialty Conference on Cold-Formed Steel Structures (1971 - 2018)

Cold-formed steel sections are often used as wall studs or floor joists and such sections often include web holes for ease of installation of services. The holes are normally punched or bored and are unstiffened; when the holes are near to points of concentrated load, web crippling can be the critical design consideration. Recently, a new generation of cold-formed steel channel sections with edge-stiffened circular holes has been developed. The web holes are stiffened through a continuous edge stiffener/lip around the perimeter of the hole. In this paper, a combination of experimental investigations and non-linear finite element analyses are used …


On The Effect Of Web Stiffening Of Cold-Formed Steel Thin-Walled Lipped Sigma Sections In Compression Members, Rashideddin Cheraghi, Hamidreza Mohammadzadeh Nov 2018

On The Effect Of Web Stiffening Of Cold-Formed Steel Thin-Walled Lipped Sigma Sections In Compression Members, Rashideddin Cheraghi, Hamidreza Mohammadzadeh

CCFSS Proceedings of International Specialty Conference on Cold-Formed Steel Structures (1971 - 2018)

Cold-formed steel cross sections are high strength thin-walled profiles which are highly prone to local and distortional instabilities. Stiffening techniques are utilized in the industry as a solution to enhance local and distortional buckling strengths. The sigma section is that channel section which its web pushed inward for the stiffening reason. In this research, the effect of side sway of the web (dx) on the buckling behavior of lipped sigma sections is investigated. The results demonstrate that stiffening inclined components of the web in lipped sigma sections for dx up to 0.5512”(14 mm) act as a stiffener and change the …


The Impact Of Bearing Conditions On The Behavior Of Cold-Formed Steel Stud Assemblies, Abbas Joorabchian, Zhanjie Li, Kara D. Peterman Nov 2018

The Impact Of Bearing Conditions On The Behavior Of Cold-Formed Steel Stud Assemblies, Abbas Joorabchian, Zhanjie Li, Kara D. Peterman

CCFSS Proceedings of International Specialty Conference on Cold-Formed Steel Structures (1971 - 2018)

The objective of this study is to explore the structural response of cold-formed steel stud assemblies (i.e., stud and track) with partial bearing conditions. It is hypothesized that studs bearing under partial bearing conditions (i.e., not fully bearing on a concrete slab) may result in reduced axial capacities. Currently, the behavior of these systems on concrete slabs due to member instabilities is not well-understood, and cold-formed steel design specifications provide no guidance. This study provides an integral experimental and numerical investigation of the stability response of the studs under partial bearing conditions in order to quantify the reduction of their …


Finite-Element Analysis Of The Eaves Joint Of Cold-Formed Steel Portal Frames Having Single Channel-Sections, Pouya Pouladi, John Ronaldson, George Charles Clifton, Jason Maxwell Ingham, Andrzej M. Wrzesien, Paul Milewski, James B. P. Lim Nov 2018

Finite-Element Analysis Of The Eaves Joint Of Cold-Formed Steel Portal Frames Having Single Channel-Sections, Pouya Pouladi, John Ronaldson, George Charles Clifton, Jason Maxwell Ingham, Andrzej M. Wrzesien, Paul Milewski, James B. P. Lim

CCFSS Proceedings of International Specialty Conference on Cold-Formed Steel Structures (1971 - 2018)

A finite element model is described for the eaves joint of a cold-formed steel portal frame that comprises a single channel section for the column and rafters eaves connections. The members are connected to the brackets through both screws and bolts. Such a joint detail is commonly used in practice in New Zealand and Australia, where the function of the screws is to prevent slip of the joint during frame erection since the bolt holes are detailed for nominal clearance. The results of the finite element model are compared against two experimental test results. In both, the critical mode of …


Experimental Study Of Apex Connection Stiffness And Strength Of Cold-Formed Steel Double Channel Portal Frames, J. Peng, J. Bendit, H. B. Blum Nov 2018

Experimental Study Of Apex Connection Stiffness And Strength Of Cold-Formed Steel Double Channel Portal Frames, J. Peng, J. Bendit, H. B. Blum

CCFSS Proceedings of International Specialty Conference on Cold-Formed Steel Structures (1971 - 2018)

Cold-formed steel portal frames are an increasingly popular structure in the housing and industrial sectors, and are commonly used for garages, sheds, and shelters. Longer span cold-formed steel portal frames are relatively new to the market, and as a result limited design guidance and recommendations exist, including the strength and stiffness of the connections. The apex connection stiffness affects the distribution of internal actions and deflections of a portal frame, and therefore, it is necessary to quantify the apex stiffness for use in design models to accurately determine the frame behavior. An experimental program was carried out on a series …


Shear Resistance Mechanisms On Steel Sheet Shear Walls With Burring Holes And Cross-Rails, Yoshimichi Kawai, Kazunori Fujihashi, Shigeaki Tohnai, Atsushi Sato, Tetsuro Ono Nov 2018

Shear Resistance Mechanisms On Steel Sheet Shear Walls With Burring Holes And Cross-Rails, Yoshimichi Kawai, Kazunori Fujihashi, Shigeaki Tohnai, Atsushi Sato, Tetsuro Ono

CCFSS Proceedings of International Specialty Conference on Cold-Formed Steel Structures (1971 - 2018)

Steel sheet shear walls with burring holes are employed in low and mid-rise buildings in seismically active regions. A configuration with burrs on the inside enables the thinner wall and omitting the machining of equipment holes. The effects of cross-rails which are generally designed to strengthen the bearing capacities of the studs, on 2.73~4.53m height shear walls were clarified by finite element analysis and experiments. Post-buckling behavior depends on tension fields restrained by the cross-rails. The formulas of the allowable strengths and the indexes of ultimate strengths were developed using the mechanisms.


Development, Training, Education, And Implementation Of Low-Cost Sensing Technologies For Bridge Structural Health Monitoring (Shm), Fernando Moreu, Chris Lippitt, Dilendra Maharjan, Marlon Aguero, Roya Nasimi Nov 2018

Development, Training, Education, And Implementation Of Low-Cost Sensing Technologies For Bridge Structural Health Monitoring (Shm), Fernando Moreu, Chris Lippitt, Dilendra Maharjan, Marlon Aguero, Roya Nasimi

Publications

Transportation infrastructure needs continuous monitoring. However, traditional inspections cost money and are conducted visually. New technologies for bridge monitoring are expensive and complex. This project involved developing cost-effective sensor technologies that can be applied towards the maintenance of railroad bridges by recording reference-free transverse displacement. More specifically, this project developed new applications of new technologies (Arduino, wireless smart sensors, drones, Hololens) and promoted workforce development with an emphasis on outreach of high-school students. This project was carried out in three main phases: (1) development and validation of technologies, (2) education and outreach to students, and (3) outreach to industry consisting …


Sustainability-Based Long-Term Management Of Bridges Under Multi-Hazard Exposure, Mohamed Soliman Nov 2018

Sustainability-Based Long-Term Management Of Bridges Under Multi-Hazard Exposure, Mohamed Soliman

Publications

Bridges are under deterioration due to various mechanical and environmental stressors. Hydraulic-related hazards (e.g., flood and scour), aggressive environmental conditions, and seismic events (e.g., earthquake) are recognized as the most significant threats to the safety of bridges. In traditional risk assessment methods for structures susceptible to damage due to floods and other natural hazards (e.g., corrosion and seismic events), future hazard predictions are conducted using historic return periods and climate records. However, recent increase in flood intensity in central-southern states indicate that future hazard occurrence rate may not necessarily follow past trends. Accordingly, current design, assessment, and management methodologies should …


Feasibility Of Distributed Fiber Optic Sensor For Corrosion Monitoring Of Steel Bars In Reinforced Concrete, Liang Fan, Yi Bao, Genda Chen Nov 2018

Feasibility Of Distributed Fiber Optic Sensor For Corrosion Monitoring Of Steel Bars In Reinforced Concrete, Liang Fan, Yi Bao, Genda Chen

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

This study investigates the feasibility of distributed fiber optic sensor for corrosion monitoring of steel bars embedded in concrete. Two sensor installation methods are compared: (1) attaching the sensor along the bar and (2) winding the sensor on the bar. For the second method, optical fibers were winded spirally on steel bars with different spacings: 0 mm, 2 mm, 5 mm, and 10 mm. Steel bar pull-out testing was conducted to evaluate the effect of presence of distributed sensor on the bond strength of steel—concrete interface. Electrochemical testing was carried out to assess the influence of the installation methods on …