Civil and Environmental Engineering Commons^™

Water Distribution Modeling, Thomas M. Walski, Donald V. Chase, Dragan A. Savic

Civil and Environmental Engineering and Engineering Mechanics Faculty Publications

To effectively use water distribution models, the engineer must be able to link knowledge of basic hydraulic theory and the mechanics of the program with that of the operation of real-world systems. Water Distribution Modeling does just that.

Written by industry experts, it provides a practical resource for engineers and modelers that goes well beyond being a how-to guide for typing data into a computer program. It contains straightforward answers to common questions related both to modeling and to distribution systems in general.

This textbook walks the practicing engineer or student through the modeling process from start to finish — …

Corrosion Of Galvanized Fasteners: Appendix, Steel Framing Alliance

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

No abstract provided.

Performance Comparison Of A Roundabout Versus Two-Way Stop Controlled (Twsc) Intersections, Deogratias Eustace

Civil and Environmental Engineering and Engineering Mechanics Faculty Publications

The superior safety record of modern roundabouts is well known in Western Europe, Australia and in most British-influenced countries around the world. The experience from a single modern roundabout installed in the City of Manhattan, Kansas, some three years ago, also shares the same experience. A major study of the performance of Manhattan, Kansas, modern roundabout was conducted at Kansas State University (KSU) and was co-sponsored by Mac-Blackwell National Rural Transportation Study Center, Kansas State University, and the City of Manhattan. The study examined three intersections, one modern roundabout and two Two-Way Stop Controlled (TWSC) intersections with similar traffic conditions. …

Another Look At The L'Ambiance Plaza Collapse, Rachel Martin, Norbert J. Delatte

Civil and Environmental Engineering Faculty Publications

The collapse of the L'Ambiance Plaza building, under construction in Bridgeport, Conn., in 1987, killed 28 construction workers. A number of concurrent investigations were undertaken to attempt to determine the cause. At least six separate theories were developed. However, a prompt legal settlement kept these investigations from being completed. This paper reviews the collapse and discusses the competing theories. The failure focused controversy on the safety of the lift-slab construction method. Because there is a need in civil engineering education for case studies to illustrate ethical and professional issues as well as technical principles, this paper also addresses these aspects. …

Experimental Investigation Of Cold-Formed Steel Beam-Column Sub-Frames: Pilot Study, M. F. Wong, K. F. Chung

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

This paper presents the findings of an experimental investigation on the structural performance of bolted moment connections in cold-formed steel beam-column sub-frames. A total of eight tests with three different connection configurations in both internal and external columns were carried out. Double lipped C-sections back-to-back with hot rolled steel gusset plates of 10 mm and of 16 mm in two different shapes were tested; four bolts per member were used in the connections. Among the tests, three different modes of failure were identified and the measured moment resistances at the connections were found to vary from 36% to 97% of …

Fire Resistance Of Loadbearing Lsf Assemblies, Farid Alfawakhiri, Mohamed A. Sultan

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

This paper presents an analytical thermal-structural model for loadbearing lightweight steel framed (LSF) walls exposed to fire on one side. The model reflects temperature and deformation data from six standard fire resistance tests conducted recently by the National Research Council of Canada in partnership with the North American steel industry. Some characteristic patterns in thermal transmission and structural behaviour are discussed. Temperature histories across LSF assemblies are simulated numerically by explicit integration of transient heat transfer equations. The apparent thermal properties are calibrated for gypsum board and three types of insulation. Analytical procedures are presented to simulate lateral deformation histories …

A General Design Rule For Bearing Failure Of Bolted Connections Between Cold-Formed Steel Strips, K. F. Chung, K. H. Ip

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

This paper presents the results of a finite element investigation on the structural performance of cold-formed steel bolted connections. A parametric study on various connection configurations was performed to relate the bearing resistances of cold-formed steel bolted connections with steel strengths and thicknesses, and bolt diameters. A semi-empirical design rule for bearing resistances of bolted connections based on finite element results is proposed in which the bearing resistances are directly related with the design yield strength, and the design tensile strength of steel strips, steel thickness, and also with bolt diameters. Design expressions for resistance contributions due to both bearing …

Evaluation Of Cold-Formed Steel Connections Attached With Pneumatically Driven Pins, Wimal Suaris, Stuart Werner Baur

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

A comprehensive experimental study was conducted to examine the shear and tensile strength of pneumatically driven pin connections used in cold-formed steel construction. This study included the key parameters that influence the connection strength: steel thickness (16-, 18- and 20-gauge steel), sheathing thickness (1/2" Unipan and 1/2" Dens-Glass Gold). The shear design values given in the AlSI design specifications for screw connections are compared with those obtained from a series of lap shear tests and a good agreement is obtained. Initial analysis of the AlSI design equation for tensile failure due to pull-over yielded poor results when compared to the …

Lessons From Recent Collapses Of Metal Buildings, David B. Peraza

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

This paper presents case studies of three roof collapses of metal buildings, discusses the most signigicant features of each case, and summarizes lessons learned that can be used to reduce future failures.

Estimation Of Restraint Forces For Z-Purlin Roofs Under Gravity Loads, M. C. Neubert, Thomas M. Murray

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

The current specification provisions for the prediction of lateral restraint forces in Z-purlin supported roof systems under gravity loads are in Section D3.1 of the 1996 AlSI Specification for the Design of Cold-Formed Steel Structural Members (1996). The provisions need refinement, because they are empirical, have an incorrect treatment of roof slope and system effects, and ignore the effect of panel stiffness on restraint forces. Therefore, a new restraint force design procedure, having a stronger reliance on engineering principles, is proposed. Elastic stiffness models, with varying roof slope, panel stiffness, and cross-sectional properties, were used to develop the procedure. A …

Compression Tests On Cold-Formed Angles Loaded Parallel With A Leg, Dan Popovic, Kim J. R. Rasmussen, Gregory J. Hancock

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

This paper describes a series of compression tests on cold-formed equal angles with slender cross-section. The angles were tested between pinned ends and loaded axially with eccentric load which caused bending parallel with a leg. The test data are compared with the design rules of the Australian and American specifications for cold-formed and hot-rolled steel structures, as well as the ASCE Standard for the Design of Latticed Steel Transmission Structures. The rules of the specifications for cold-formed steel structures (AS/NZS4600 and AlSI) are shown to be very conservative. The cause of the conservatism is explained and improved design rules are …

On The Structural Behavior Of Composite Beams Using Cold-Formed Shapes, Maximiliano Malite, Walter A. Nimir, Jose Jairo De Sales, Roberto Martins Goncalves

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

Cold-formed shapes have been increasingly employed in the construction of small multiple-floored buildings in Brazil, because wide flange shapes required to meet the demand are unavailable on the Brazilian market. Because existing codes fail to cover the design of composite beams constituted of cold-formed shapes, Brazilian design engineers have usually disregarded the contribution of the slab or have adopted improvised calculations that may to lead to unsafe results. The structural behavior of composite beams, constituted of cold-formed double channel shapes and connected to the concrete slab by means of shear connectors that were also cold-formed, was investigated experimentally. Simply supported …

Flexural Wrinkling Behaviour Of Lightly Profiled Sandwich Panels, Mahen Mahendran, D. Mcandrew

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

In Australia, sandwich panels are commonly made of flat or lightly profiled steel faces and expanded polystyrene foam cores. Flexural wrinkling is often the governing criterion in the design of these panels. The use of lightly profiled faces is expected to increase the flexural wrinkling stress considerably whereas the presence of joints between the polystyrene foam slabs in the transverse direction introduces a reduction to the flexural wrinkling stress. Therefore a series of full scale experiments and finite element analyses were conducted to evaluate the effects of lightly profiled faces and transverse joints on the flexural wrinkling stress of panels …

Stub Column Tests On Cold-Formed Steel Angle Sections, M. Dhanalakshmi, N. E. Shanmugam

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

An investigation on the ultimate load capacity of non-perforated and perforated equal angle cold-formed steel stub columns is presented in this paper. An experimental study has been undertaken to study the behavior of such members subjected to compression. Members were tested to failure under axial or eccentric loading. A comparison of experimental and finite element failure loads, as well as the failure modes of tested specimens, shows that the finite element model is capable of predicting the ultimate load capacity and the failure modes with reasonable accuracy.

Lateral Buckling Of Prismatic Members About An Imposed Axis Of Rotation, Leopold K. Sokol

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

This paper deals with the lateral buckling of prismatic members whose position of the axis of rotation is imposed by the conditions of lateral support. As a function of the type of connection with the lateral support, the rotation may be free or hindered (elastic end restraint). This may concern, for instance, the case of a purlin stabilized by a roof structure or of a column stabilized by an external cladding or by another type of efficient continuous bracing. Usually, the check of this type of instability is complex and leads to sophisticated and tedious computations. In order to avoid …

Experimental Investigation Of Cold-Formed Channels Subjected To Combined Bending And Web Crippling, Ben Young, Gregory J. Hancock

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

An experimental investigation of cold-formed channels subjected to combined bending and web crippling is described in this paper. A series of tests was performed on unlipped channels rolled from high strength structural steel sheets having nominal plate thickness up to 6 mm, and a maximum web slenderness value of 45. This value is considerably lower than the intended web slenderness values used in the Australian/New Zealand Standard (AS/NZS 4600, 1996) and the American Iron and Steel Institute (AISI, 1996) Specification for cold-formed steel structures. In the past, the typical thickness of cold-formed steel members was less than 3 mm, and …

Web Crippling Of Cold Formed Steel C-And Z- Sections, B. Beshara, R. M. Schuster

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

An experimental investigation of cold formed steel stiffened C-and Z sections subjected to web crippling is presented in this paper. This study was devoted to two loading conditions according to the AISI Specification, namely End Two Flange (ETF) and Interior Two Flange (ITF) loading, with particular emphasis on large inside bend radius to thickness ratios, R, (up to 12) and the specimens being fastened to the support during testing. There is no experimental data available in the literature regarding the web crippling resistance of such members that are fastened to the support and have inside bend radius to thickness ratios …

Strength Of Bearing Stiffeners In Cold Formed C-Sections, R. M. Schuster, S. R. Fox

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

The applications of cold formed steel in residential construction have been increasing rapidly in recent years around the world. Some framing practices have been developed that are not covered by the current design specifications, such as using thin cold formed steel stud sections as web stiffeners for C-section floor joists. Earlier tests have shown that the current design methods are unconservative when applied to the types of stiffeners in common usage today. There are a number of variables that influence the capacity of these stiffeners such as stiffener type, position on the joist and connections. All parameters need to be …

Fe Models For Sheeting Under Interaction Load, Jan Kerstens, Bert Snijder, Monique Bakker, H. Hofmeyer

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

Experiments show that, after ultimate load, sheeting may fail by three distinct post-failure modes. In this paper, three finite element models are presented, one for each post-failure mode. One of the finite element models was difficult to develop. A spring model explains this. The finite element models show that, at ultimate load, only two different ultimate failure modes exist. This is important for the development of mechanical models for sheeting failure.

A Design Approach For Complex Stiffeners, Andrew T. Sarawit, Teoman Pekoz

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

This paper presents a design approach for laterally braced cold-formed steel flexural members with edge stiffened flanges other then simple lips. The design method for flexural members given by Schafer and Pekoz (1999) is used here for designing these complex stiffeners. The method integrates distortional buckling into the unified effective width approach currently used in most cold-formed steel design specifications. A finite element method was first used to investigate the post-buckling behavior and carry out initial geometric imperfection sensitivity studies for various types of stiffeners. Then parametric studies were carried out for different types of stiffeners to compare the moment …

Cyclic Pull-Out Strength Of Steel Roof And Wall Cladding Systems, Mahen Mahendran, Dhammika Mahaarachchi

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

When crest-fixed thin steel roof cladding systems are subjected to wind uplift, local pull-through or pull-out failures occur prematurely at their screwed connections. During high wind events such as storms and cyclones these localised failures then lead to severe damage to buildings and their contents. In recent times, the use of thin steel battens/purlins has increased considerably. This has made the pull-out failures more critical in the design of steel cladding systems. Recent research has developed a design formula for the static pull-out strength of steel cladding systems. However, the effects of fluctuating wind uplift loading that occurs during high …

Knee Joints In Cold-Formed Channel Portal Frames, Julie Mills

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

Light gauge cold-formed channel sections are frequently used in portal frame construction for small span agricultural and industrial sheds. A testing program at the University of South Australia has shown that the knee joint currently used in these sheds fails at bending moments well below required design values. An alternative joint construction using multiple Teks screws is being developed and is exhibiting much better performance.

Pull-Through Failures Of Crest-Fixed Steel Claddings Initiated By Transverse Splitting, Dhammika Mahaarachchi, Mahen Mahendran

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

Crest-fixed steel claddings made of thin, high strength steel often suffer from local pull-through failures at their screw connections during high wind events such as storms and hurricanes. Currently there aren't any adequate design provisions for these cladding systems except for the expensive testing provisions. Since the local pull-through failures in the less ductile steel claddings are initiated by transverse splitting at the fastener hole, analytical studies have not been able to determine the pull-through failure loads. Analytical studies could be used if a reliable splitting criterion is available. Therefore a series of two-span cladding tests was conducted on a …

Lateral Strength Of Wind Load Bearing Wall Stud-To-Track Connection, R. M. Schuster, S. R. Fox

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

A common application of cold formed steel in building construction is for wind load bearing steel studs (curtain walls). These wall studs are designed to carry lateral load only, and frame into horizontal steel track members at the top and bottom of the wall assembly. The stud-to-track connection consists of studs framing perpendicularly into the track and are connected with sheet metal screws. The design of the wall stud must include a check of the web crippling capacity at the end reactions. The current design expressions, however, do not apply to the type of bearing in these stud-to-track connections. Reported …

Tests And Design Of Cold-Formed Unlipped Channels Subjected To Web Crippling, Ben Young, Gregory J. Hancock

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

A series of tests on cold-formed unlipped channels subjected to web crippling is presented in this paper. The tests were conducted under the four loading conditions specified in the Australian/New Zealand Standard (AS/NZS 4600, 1996) and the American Iron and Steel Institute (AISI, 1996) Specification for cold-formed steel structures. The four specified loading conditions are the End-One-Flange (EOF), Interior-One-Flange (IOF), End-Two-Flange (ETF) and Interior-Two-Flange (ITF) loading. The loading of concentrated load or reaction forces were applied by means of bearing plates which acted across the full flange widths of the channels. The web slenderness values of the tested channel sections …

Web Crippling Behaviour Of Channels With Flanges Restrained, Ben Young, Gregory J. Hancock

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

The paper presents a comparison of web crippling tests of cold-formed unlipped channels with flanges restrained or unrestrained. The tests were performed under end and interior two-flange loading conditions specified in the Australian/New Zealand Standard (AS/NZS 4600, 1996) and the American Iron and Steel Institute (AISI, 1996) Specification for cold-formed steel structures, namely End-Two-Flange (ETF) and Interior-Two-Flange (ITF) loading conditions. The concentrated load was applied by a bearing plate at the top flange of the channels, and the reaction force applied by an identical bearing plate at the bottom flange of the channels. The bearing plates acted across the full …

A Theoretical And Experimental Analysis Of Cold-Formed Steel Shapes Subjected To Bending - Channel And Simple Lipped Channel, Roberto Martins Goncalves, Maximiliano Malite, Carlos Eduardo Javaroni

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

Cold-formed steel shapes have been widely employed in steel construction, where they frequently offer a lower cost solution than do traditional laminated shapes. A classic application of cold-formed steel shapes is purlins in the roof panel of industrial buildings, connected to the roof panel by means of screws. The combined effect of these two elements has been the subject of investigations in some countries. Design criteria were included in the AISI Code in 1991 and 1996. This paper presents and discusses the results obtained from bending tests carried out on shapes commonly used in Brazil, i.e., the channel and the …

Calibration Of Cold Formed Steel Shear Equations, B. Craig, R. M. Schuster

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

There is a difference in the shear design criteria between the Canadian cold formed steel design Standard, CSA S136-94 (from here on referred to as S136) and the American Iron and Steel Institute Specification for the design of cold formed steel structures, AISI-96 (from here on referred to as AISI). The focus of this paper was to carry out the appropriate calibrations for the factor of safety, Ω, and the resistance factor, Ï•, using the current design approaches of both countries. In the case of the S136 Standard, only the resistance factor was determined. It was assumed at the outset …

Elastic-Plastic Interactive Buckling Of Thin-Walled Steel Compression Members, Dan Dubina, Viorel Ungureanu

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

In the actual design codes the interaction formula for local and overall buckling modes of thin-walled steel compression (TWSC) members, the effect of local buckling. is introduced by means of effective strength of short members. This paper proposes to replace, into the Ayrton-Perry interaction formula, the short member "effective" strength, which is based on the "effective width" approach by the plastic strength evaluated by means of local plastic mechanism analysis. There are some papers by Murray et al. [1,2,3], in which the plastic mechanisms corresponding to the local buckling of plates and TWSC members in compression are analysed. On this …

Finite Element Analysis Of Cold-Formed Channel Columns, Ben Young, Jintang Yan

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

The paper presents a numerical investigation into the behaviour and strengths of cold-formed plain and lipped channel columns using finite element analysis. A non-linear finite element model is developed and verified against the fixed-ended channel column tests conducted by Young and Rasmussen (1998a, 1998b and 1998c). Geometric and material non-linearities were included in the finite element model. It is demonstrated that the finite element model closely predicted the ultimate loads and the behaviour of the tested cold-formed channel columns. Hence, the model was used for an extensive parametric study of cross-section geometries. Furthermore, the results of the numerical investigation are …