Structural Engineering Commons^™

Top Arc Seam Weld Shear Strength And Stiffness For Sheet-To-Sheet Connections, R. Nunna, J. Martin, J. Mattingly, P. Bodwell, D. Boltz, K. Cullum, Roger A. Laboube

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

The North American Specification for the Design of Cold-Formed Steel Structural Members does not provide specific design guidance for sheet-to-sheet top arc seam welds in shear. A collaborative industry study has developed design guidance for both strength and stiffness of the connection to facilitate analytical evaluation of floor and roof diaphragm assemblies and wall assemblies. The test program was performed per AISI S905 and addressed material ductility, weld length, sheet thickness and the distribution of the force being transferred by the weld connection.

The Influence Of The Aspect Ratio On The Lateral Response Of The Sheathed Cold Formed Steel Walls, O. Iuorio, L. Fiorino, V. Macillo, M. T. Terracciano, R. Landolfo

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

The influence of the aspect ratio on the lateral response of cold formed steel walls is analyzed by three design methodologies. In particular the prediction provided by the AISI Lateral Design, that is at the moment the main document for the design of CFS buildings under horizontal loads, is compared with the results obtained by applying the principles of mechanics and with those provided by non-linear finite element models. This paper presents and discusses in terms of strength and stiffness the validity of the different design methodologies in case of non-conventional wall aspect ratios comparing the numerical results with available …

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 …

An Explicit, Dynamic Finite Element Model For The Local Failure Of Cold-Formed Trapezoidal Sheeting, Hèrm Hofmeyer

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

Trapezoidal sheeting, made of cold-formed, thin-walled steel, is widely used for the construction of cladding and roofs. At an interior support, the sheeting is subject to bending moments and a concentrated load, which leads to possible failure followed by two post-failure modes: the yield-arc and yield-eye modes. Until recently, it was not fully understood why a specific post-failure mode occurs and it was suggested that mode-jumping of the compressed sheeting flange may influence the mode occurring. This paper presents new research, in which both the compressed flange in isolation and the sheeting are modeled by using an explicit, dynamic finite …

Effects Of Cold-Formed Steel Framed Gypsum Partition Walls On The Seismic Response Of A Medical Facility, Ryan Davies, Rodrigo Retamales, Gilberto Mosqueda, Andre Filiatrault, Don Allen

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

The first experimental phase of the NEES Nonstructural Grand Challenge Project: “Simulation of the Seismic Performance of Nonstructural Systems” investigated the in-plane hysteretic behaviors of thirty-six full-scale cold-formed steel framed gypsum partition walls. Results of quasi-static reverse cyclic and dynamic testing on sixteen wall configurations including walls with commercial and institutional construction details and innovative connection techniques are first briefly reviewed. Thereafter, six tri-linear hysteretic models of partition walls with pinching behavior and strength and stiffness degradation are developed based on the experimental data for use in a finite element analysis platform. The partition wall models, represented by shear spring …

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 …

Design Capacity Determination Assisted By Testing Based On Lrfd Method, Y. Q. Li, L. P. Wang, Z. Y. Shen

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

In some special circumstances of structural design, adequate calculation models are not available in current specifications or they cannot be used directly for new materials or structural configurations. In these cases, tests of the prototype units may be accepted as an alternative to calculation. If this alternative procedure is adopted, corresponding requirements and evaluation of test results should apply. In this paper, a complete procedure of determining the design capacity of the test specimens based on statistical analysis and Load and resistance factor design (LRFD) method was presented: characteristic value of experimental resistance was obtained from the minimum value of …

Critical Elastic Shear Buckling Stress Hand Solution For C- And Z-Sections Including Cross-Section Connectivity, Kevin Aswegan, Cristopher D. Moen

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

This paper presents an approximate solution for the critical elastic buckling stress of cold-formed steel C- and Z-section members including cross-section connectivity. The elastic buckling solution is developed to support the extension of the Direct Strength Method to the shear ultimate limit state, where the cross sectional critical elastic shear buckling stress (load) is employed to predict shear capacity. The shear buckling stress and buckled half-wavelength are calculated with a classical energy solution for a thin plate with edges rotationally restrained. Rotational stiffness expressions in the AISI S100-07 specification, originally derived for distortional buckling of C- and Z-sections, are used …

Load Distribution In Floor To Wall Connections, D. M. Fox, D. R. Knill, R. M. Schuster

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

Presented in this paper is a cold formed steel load distribution system developed by iSPAN Systems LP that enables the installation of floor joists without the need to align them with the supporting wall studs. The floor joists are supported by a shear connection attached to a cold formed steel perimeter distribution member. In addition to the load distribution aspect, the system results in a simplified lateral design approach. An experimental verification study was carried out to establish the load distribution capability of the system, resulting in a simplified procedure to determine the connection requirements and load transfer characteristics to …

Initial Study And Verification Of A Distributed Fiber Optic Corrosion Monitoring System For Transportation Structures, Hai Xiao, Genda Chen, Zhan Gao, Ying Huang, Fujian Tang

Electrical and Computer Engineering Faculty Research & Creative Works

For this study, a novel optical fiber sensing system was developed and tested for the monitoring of corrosion in transportation systems. The optical fiber sensing system consists of a reference long period fiber gratings (LPFG) sensor for corrosive environmental monitoring and a LPFG sensor coated with a thin film of nano iron and silica particles for steel corrosion monitoring. The environmental effects (such as pH and temperature) are compensated by the use of the reference LPFG sensor. The sensor design, simulation, and experimental validation were performed in this study to investigate the feasibility of the proposed sensing system for corrosion …

Concrete Surface With Nano-Particle Additives For Improved Wearing Resistance To Increase Truck Traffic, Genda Chen, Dongming Yan, Chenglin Wu, Zhibin Lin, Nicholas Leventis, Shruti Mahadik-Khanolkar

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

This study focused on the use of nanotechnology in concrete to improve the wearing resistance of concrete. The nano materials used were polymer cross-linked aerogels, carbon nanotubes, and nano-SiO₂, nano-CaCO₃, and nano-Al₂O₃ particles. As an indirect measurement of the concrete wearing resistance, the tensile and compressive properties and the permeability of concrete were evaluated for various mix designs. The optimal amount of nano material additives were determined following the American Society of Testing Methods (ASTM) standard test methodologies. The test results from the materials were compared for their mechanical behaviors. This type of …

Sensors For Integrated Monitoring And Mitigation Of Scour, Genda Chen, David Pommerenke, Zhi Zhou, Ying Huang

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Systems and methods for detecting scour. Some embodiments provide systems which include a sensor and a signal generator with a combined density equal to or greater than that of water. Optionally, the sensor can be a magnet, magnetic resonator, or accelerometer. In some embodiments, the sensor is adapted to be placed in regions potentially subject to scour and to sense a scour-related condition. The signal generator generates a wireless signal conveying data regarding the as-sensed scour-related. In some embodiments the sensor is the signal generator while a receiver of the wireless signal can include an antenna, a magnetometer, or an …

Use Of Mill Certficates To Establish Material Properties In Testing Of Colf-Formed Steel Compoenents, Tim Stauffer, Paul Mcentee

CCFSS Library (1939 - present)

Testing is often used to establish the available strength of cold-formed steel components. The evaluation of this test data requires adjustment based on the material properties of the tested components to account for values that exceed the minimum specified values. Currently, it is required that this adjustment be based on samples taken from the tested specimen or the flat sheet used to form the test specimen. However, in many cases it is not practical to obtain these samples. Instead, it is desired to permit an alternate that allows the use of mechanical properties reported by the steel supplier. The purpose …

Steel Building Assessment In Post-Earthquake Fire Environments With Fiber Optical Sensors, Genda Chen, Ying Huang, Hai Xiao

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

No abstract provided.

North American Standard For Cold-Formed Steel Framing -- Nonstructural Members, 2011 Edition, American Iron And Steel Institute

American Iron and Steel Institute (AISI) Specifications, Standards, Manuals and Research Reports (1946 - present)

No abstract provided.

Code Of Standard Practice For Cold-Formed Steel Structural Framing, 2011 Edition, American Iron And Steel Institute

American Iron and Steel Institute (AISI) Specifications, Standards, Manuals and Research Reports (1946 - present)

No abstract provided.

China Earthquake Reconnaissance Report: Performance Of Transportation Structures During The May 12, 2008, M7.9 Wenchuan Earthquake, Wen-Huei Phillip Yen, Genda Chen, Mark Yashinski, Youssef M.A. Hashash, Curtis J. Holub, Kehai Wang, Xiaodong Guo

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

This report documents the lessons learned from damage caused in the May 12, 2008, M7.9 earthquake in Wenchuan County, China. The damage to the 14 observed bridges reminded the researchers of damage suffered during the 1971 San Fernando Earthquake in California. The bridges had few seismic details such as long seats, large shear keys, or tightly spaced transverse reinforcement. Most arch and girder bridges collapsed due to surface rupturing of the seismic faults in the Longmen-Shan thrust zone. A significant portion of roadways and bridges were pushed away or buried by landslides in the steep slopes of mountainous terrain. Damage …

Post-Earthquake Reconnaissance Report On Transportation Infrastructure Impact Of The February 27, 2010, Offshore Maule Earthquake In Chile, Wen-Huei Phillip Yen, Genda Chen, Ian G. Buckle, Tony M. Allen, Daniel E. Alzamora, Jeffrey Ger, Juan G. Arias

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

This report documents the findings and lessons learned from the February 27, 2010, M8.8 offshore Maule earthquake in Chile. Fewer than 0.15 percent of the bridges in Chile's inventory, most built after 1995, collapsed or suffered damage that rendered them useless. Many spans of precast prestressed discontinuous girder bridges with continuous decks fell off their supports, probably due to significant in-plane rotation of the superstructure as a result of severe shaking. Lateral steel stoppers used to provide both vertical and lateral restraints on girders were largely unsuccessful due to their inadequate connection detail to cap beams and abutments. Reinforced concrete …

Accelerated Construction For Pedestrian Bridges: A Comparison Between High Strength Concrete (Hsc) And High-Strength Self Consolidating Concrete (Hs-Scc), John J. Myers, Kurt Bloch

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

High-strength concrete (HSC) and glass fiber reinforced polymer (GFRP) bars are materials utilized in bridge construction to lower cost, reduce construction time, and increase service life of bridge structures. Recently, high-strength self-consolidating concrete (HS-SCC), a highly flowable concrete that does not require vibration, has been developed as a viable alternative to HSC for use in situations with congested steel or a need for rapid construction. Coupling HS-SCC with GFRP bars could create durable structures built rapidly. Several performance related issues remain to be investigated such as the behavior of prestress loss, shear, creep, shrinkage, thermal gradients, mechanical property development, time …

Modern Protection Systems To Prevent Corrosion Of Structural Steel Elements Due To Deicing And Roadway Salts, John J. Myers, Wei Zheng

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

The effectiveness of innovative polymeric coatings, polyurea and Poly aspartic polyurea, to protect structural steel from corrosion was investigated through standard laboratory tests. the coating evaluation tests included salt fog test, QUV weathering test, adhesion test, and freeze-thaw stability test. These tests were used to assess the long-term performance of coating technologies compared to the conventional polyurethane type coatings, i.e. coating systems with inorganic zinc primer, epoxy intermediate coat and polyurethane topcoat. This paper presents part of results in the aforementioned evaluation tests. the results illustrate that Poly aspartic coating systems are very promising for corrosion mitigation and can provide …

Buckling Of Profiled Steel Diaphragms, Rao V. Nunna

CCFSS Library (1939 - present)

No abstract provided.

Corrosion-Resistant Glasses For Steel Enamels, Richard K. Brow, Signo Tadeu Dos Reis, Michael L. Koenigstein, Genda Chen

Materials Science and Engineering Faculty Research & Creative Works

A cementitious composite material wherein glass-coated steel rods are positioned in a cementitious matrix. The glass composition for coating the steel reinforcing rods includes between about 33-45 weight percent SiO₂, 13.5-19.5 weight percent B₂O₃, 3.5-4.6 weight percent Al₂O₃, 4.0-13.5 weight percent K₂O, 5.5-15.5 weight percent ZrO₂, 8.6-15.9 weight percent Na₂O, 4.6-5.1 weight percent CaO, 0.6-0.7 weight percent MnO₂, 1.0-1.0 weight percent NiO, and 1.0-1.1 weight percent CoO. The glass composition is typically in compression on the rods at ambient temperatures, has a …

Design Guide For Cold-Formed Steel Purlin Roof Framing Systems, American Iron And Steel Institute (Aisi)

American Iron and Steel Institute (AISI) Specifications, Standards, Manuals and Research Reports (1946 - present)

"The Design Guide for Cold-Formed Steel Purlin Roof Framing Systems provides information for the designer of single span and continuous multiple span steel purlin-supported roof systems with an emphasis on the design anchorage systems. The Design Guide is based on the American Iron and Steel Institute (AISI) North American Specification for the Design of Cold-Formed Steel Structural Members, 2007 Edition. Where the Specification is silent on design issues, the procedures are based on published references and on the opinions of the authors.

The Design Guide was co-sponsored by the American Iron and Steel Institute (AISI) and the Metal Building …

Calibration Of Load And Resistance Factors In Lrfd Foundation Design Specifications, Zuocai Wang, Genda Chen, Oh-Sung Kwon, Sarah Orton

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

This report summarizes the findings and recommendations on the impact of foundation settlements on the reliability of bridge superstructures. As a collaborative effort of an overall initiative for the development of LRFD foundation design specifications, this study is focused on the investigatio of pros and cons for including foundation settlements in bridge designs under gravity loads. Settlement was modeled both probabilistically and deterministically. In the case of a random settlement variable, a lognormal distribution was used in reliability analysis with a fixed coefficient of variation of 0.25. Dead and live loads were modeled as random variables with normal and Gumbel …

High-Strength Selfconsolidating Concrete Girders Subjected To Elevated Compressive Fiber Stresses, Part 2: Structural Behavior, Jared E. Brewe, John J. Myers

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

The design of prestressed concrete members is restricted by the requirement that the extreme compressive fiber stress at midspan be less than 60% of the concrete compressive strength at release of prestressing. the purported purpose of this limit is to provide serviceability performance, but it places unnecessary limits on the capability of the materials. for this research program, six prestressed concrete girders were produced with high-strength, self-consolidating concrete and subjected to elevated compressive fiber stress levels ranging from 65% to 84% of initial concrete compressive strength at release of prestressing. Part 1 of this series analyzed time-dependent prestress losses and …

Product Technical Information, Steel Stud Manufacturers Association

CCFSS Library (1939 - present)

No abstract provided.

Cold-Formed Steel Framing Seismic Design Optimization Phase 1a: Seismic Equivalency Parameter Evaluation, American Iron And Steel Institute

American Iron and Steel Institute (AISI) Specifications, Standards, Manuals and Research Reports (1946 - present)

No abstract provided.

A Life-Cycle Assessment Of Cold-Formed Steel Enclosures Verses Alternative Enclosures In Commerical Buildings, K. J. Van, L. Xu

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

In North America, the operation of buildings accounts for approximately one third of the total energy use and greenhouse gas emissions each year. Over the life of a building, the total energy use is a combination of the embodied energy in the building materials and the operating energy of the building. Building enclosures (walls and roofs) have a huge impact on both the embodied energy and the operating energy of buildings. Historically, steel has been blacklisted as a material with a high embodied energy. This has led to a misconception that steel enclosures use significantly more energy than other enclosure …

Behavior And Design Of Axially Compressed Sheathed Wall Studs, L. C. M. Vieira Jr., B. W. Schafer

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

The objective of this paper is to summarize efforts in a multi year project dedicated to developing a reliable design method for cold - formed steel wall studs that rely on sheathing for bracing. Testing on single columns with sheathing, and full - scale walls with sheathin g, are summarized. Particular emphasis is placed on the observed limit states given the different sheathing conditions. The sheathing supplies beneficial restraint to the wall studs and the stiffness of this sheathing - based restraint is characterized exper imentally and analytically. A unique application of the Direct Strength Method of design is explored …

Lateral Torsional Instability Of Single Channels Restrained By Angle Cleats, G. M. Bukasa, M. Dundu Masce

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

A series of experiments on the lateral tors ional instability of single channels is presented. The channels are restrained by a purlin – angle cleat connection and subjected to a two point loading system in order to simulate a distributed load. Failure of the channels occurred by local buckling of the compression zone of the flange and web and lateral torsional buckling of the channels between points of lateral support. Tests have shown the purlin–angle cleat connection to be capable of restraining the frames from failing due to lateral-torsional buckling. This eliminates the idea of having fly-bracings, which is normally …