Civil and Environmental Engineering Commons^™

Estimating The Usle - Soil Erodibility Factor In Developing Tropical Countries:A Case Study In Tanzania, Metthew Mulengeral

Tanzania Journal of Engineering and Technology (TJET)

Developing countries in the tropics are facing more soil erosion problems than the developed temperate countries. These developing countries have no accurate locally applicable equation(s) for predicting soil erosion or for planning and implementation of soil conservation measures. Furthermore, These countries do not have the necessary resources to develop the soil loss prediction equation(s). Existing empirical equations like the Universal Soil Loss Equation (USLE) if modified to suit tropical conditions can be useful a tool in soil erosion control in the region for a foreseeable future. In this paper equations'for estimating the soil erodibility factor in the USLE for tropical …

Technical And Economic Comparison Of Performance Between Farmer And Government Managed Irrigation Schemes In Tanzania: A Case Study Of Kapunga Irrigation Project, D Chemka

Tanzania Journal of Engineering and Technology (TJET)

This paper conwares the perforinance Of governnyent ro fanner-managed irrigation schemes at Kapunga Rice Project in Mbeya Region, south-west Tanzania. The results showed that the farmer-managed irrigation scheme (FMIS) performed better than the government-managed irrigation scheme (GMIS) in attaining good performance. Applicable indicators for farmer-managed irrigation scheme are as shown below with those of government-managed scheme indicated in brackets. Its overall irrigation efficiency was 61' percent (29 percent) average productivity was 3.2 ton/liG (2.2 ton/ha); economic profirability: internal rate of return was 3.2 percent (5 percent), benefit/cost ratio of 0.60 (0.14); while its financial profitability: internal rate of return was …

Determination Of The Tensile And Shear Strengths Of Screws And The Effect Of Screw Patterns On Cold-Formed Steel Connections, Marc Allen Sokol, Roger A. Laboube, Wei-Wen Yu

CCFSS Library (1939 - present)

PREFACE This report summarizes two studies related to the design of cold-formed steel connections. The study topics included the creation of a test standard for determining the strength of a screw, and the determination of the strength of a screw connection. A standard test protocol does not exist for determining the strength of a screw. Today, manufacturers use test protocols developed for their products. Thus, there is no consistency in defining the structural performance of a screw. A test standard has been developed. The standard used as its model the American Society of Testing and Material's F 606, Standard Test …

Registration Violations And The Use Of Optical Character Recognition Technology At Kentucky Weigh Stations, Jennifer R. Walton, Joseph D. Crabtree

Kentucky Transportation Center Research Report

As a Model Deployment State for CVISN (Commercial Vehicle Information Systems and Networks), Kentucky is valuating and improving its procedures related to commercial vehicle administration and enforcement. As part of this effort, the Kentucky Transportation Center (KTC) was asked to investigate the frequency of registration-related violations at Kentucky weigh stations and the potential effectiveness of a license plate recognition (LPR) system in detecting and deterring such violations. Typical violations considered in the investigation included using an expired license plate, hauling weight in excess of the truck’s registered weight, or traveling in Kentucky without proper authority.

KTC researchers first examined Kentucky’s …

Seismic Evaluation Of The Ohio River Bridge On Us51 At Wickliffe, Kentucky, Issam E. Harik, Chelliah Madasamy, Denglin Chen, Leonong Zhou, Kevin Sutterer, Ron Street, David L. Allen

Kentucky Transportation Center Research Report

This report presents the of seismic evaluation of the Ohio river bridge on US51 at Wickliffe, Kentucky. The main bridge is a five-span single-deck cantilever through-truss type. The approach bridge has 21 spans on the Kentucky side and 6 spans on the Illinois side. Although this bridge has not yet been subjected to a moderate or major earthquake, it is situated within the influence of the New Madrid seismic zone.

The seismic evaluation program consists of field testing and seismic response analysis. The modal properties of the main bridge are determined through field testing, and are used to calibrate the …

Evaluation Of 93-Inch Corrugated Metal Culvert On Ky 693 And Us 23, Green-Up County, L. John Fleckenstein, Richard Reitenour, David L. Allen

Kentucky Transportation Center Research Report

No abstract provided.

Probabilistic Life Cycle Cost Analysis Fhwa Demonstration Project Dp 115, R. Clark Graves, David L. Allen

Kentucky Transportation Center Research Report

Kentucky has been involved in several projects relating to the development of a Life Cycle Cost (LCC) analysis procedures of pavement structures. Research projects have been conducted by the Kentucky Transportation Center dealing with development of a more robust LCC procedures for pavement analysis. A research project has also been conducted developing network level LCC procedures. These procedures are currently in the evaluation phase and have not been implemented into current Kentucky Transportation Cabinet procedures. Life Cycle Costs analysis is utilized on various projects throughout Kentucky to evaluate various pavement construction and rehabilitation alternatives.

This report will outline the current …

Evaluation Of Reference Markers, Jerry G. Pigman

Kentucky Transportation Center Research Report

The objective of this research evaluation was to evaluate the reference markers which were installed on sections of interstates and freeways in the Cincinnati-northern Kentucky area, the Lexington-Fayette Urban County area, the Louisville-southern Indiana area, and the Indianapolis area. The evaluation was conducted to determine if the use of reference markers at spacings of 0.1 or 0.2-mile intervals could improve the effectiveness of the emergency response and incident management processes. Also evaluated were color of the markers and the placement location within the right-of-way. Both "'white on blue" and ''white on green" markers were installed on various projects, with some …

Bs News

Building Services Engineering

No abstract provided.

Model For Trace Metal Exposure In Filter-Feeding Flamingos At Alkaline Rift Valley Lake, Kenya, Yarrow M. Nelson, Ramesh J. Thampy, Gideon K. Motelin, Jackson A. Raini, Cynthia J. Disante, Leonard W. Lion

Civil and Environmental Engineering

Abstract—Toxic trace metals have been implicated as a potential cause of recent flamingo kills at Lake Nakuru, Kenya. Chromium (Cr), copper (Cu), lead (Pb), and zinc (Zn) have accumulated in the lake sediments as a result of unregulated discharges and because this alkaline lake has no natural outlet. Lesser flamingos (Phoeniconaias minor) at Lake Nakuru feed predominantly on the cyanobacterium Spirulina platensis, and because of their filter-feeding mechanism, they are susceptible to exposure to particle-bound metals. Trace metal adsorption isotherms to lake sediments and S. platensis were obtained under simulated lake conditions, and a mathematical model was …

Predictive Relationships For Uptake Of Organic Contaminants By Hybrid Poplar Trees, Joel Gerard Burken, Jerald L. Schnoor

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Twelve Organic Compounds Commonly Found at Hazardous Waste Sites Were Studied for Uptake by Hybrid Poplar Trees. the Vegetative Uptake of Many of These Compounds Has Not Previously Been Demonstrated for Plant Species Being Utilized for Phytoremediation, Such as Hybrid Poplar Trees. Experiments Were Conducted Hydroponically Utilizing 14C-Labeled Compounds to Ascertain Translocation and Fate. Predictive Relationships for the Translocation and Partitioning to Plant Tissues Were Developed from the Experimental Data. Translocation and Partitioning Relationships based on Compounds' Octanol- Water Partitioning Coefficients (100 K(Ow)) Produced the Best Results, But the Relationships Did Not Allow for Fully Accurate Prediction of Each Contaminant's …

Bs News

Building Services Engineering

No abstract provided.

Buckling Mode Interaction In Cold-Formed Steel Columns And Beams, C. Jiang, Viorel Ungureanu, J. Michael Davies

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

The buckling behaviour of cold-formed steel columns and beams is far from simple. The three generic forms of buckling, namely local buckling, distortional buckling and overall buckling, generally have different wavelengths and are usually restricted to different span ranges. However, there is also the possibility of interaction among these buckling modes at a certain span length. Thus, local plate buckling and distortional buckling may occur together with lateral-torsional buckling in such a way that they all have an influence on the ultimate load carrying capacity of a member. The influence of local buckling is taken into consideration in design codes …

Spacing Of Connections In Compression Flanges Of Built-Up Cold-Formed Steel Beams, Roger A. Laboube, Wei-Wen Yu, Michael L. Jones

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

Built-up cold-formed steel sections may offer greater economy in building construction. Typical built-up sections are cellular decks or door and window header beams. A research project was initiated to determine if the current spacing criteria outlined in Section D1.2 of the AISI Specification accurately predicted the capacity of built-up sections with the cover plate in compression. This study showed that criteria No.2 of the AISI Design Specification spacing criteria is restrictive when applied to built-up cross sections in bending. All test sections continued to carry additional load after the cover plate buckled. The tests showed that as the spacing of …

Bending Tests Of Hat Sections With Multiple Longitudinal Stiffeners, V. V. Acharya, R. M. Schuster

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

This paper is the first in a series of articles that report findings of the authors investigation into the behavior of cold formed steel hat sections in bending with multiple intermediate longitudinal stiffeners. Presented in this paper is the test program that was carried out at the University of Waterloo as part of a two year research program. It is known that sections with multiple intermediate stiffeners can fail either in a local sub-element buckling mode, or alternatively, can experience an overall plate buckling mode of failure. Although both failure modes were examined, the main objective was to develop a …

Accelerated Test Development For Coil-Coated Steel Building Panels, K. M. Lawson, H. H. Lawson, H. E. G. Rommal, A. C. Tiburcio

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

This paper discusses the experimental design and the preliminary findings of an ongoing project designed to establish an accelerated laboratory test that would rank coating system performance the same as their performance in atmospheric exposure. A total of ten materials are included in the program: four substrates each with two coating systems and one substrate with two additional coating systems. Samples were installed at four atmospheric exposure sites: Middletown, OH, Daytona Beach, FL, Monroeville, PA, and Halifax, NS, Canada. Three different orientations were utilized at each of the exposure sites and a variety of building panel features were included on …

Experimental Procedures For Stub Column Tests, Y. Pu, M. H. R. Godley, R. G. Beale

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

In this paper a total of 36 stub columns was tested by two different experimental procedures, namely the FEM and AISI procedures, to investigate the difference in the ultimate load between these procedures. Of these 26 were carried out in the pin-ended condition according to FEM, the rest were in the fixed-end condition according to AlSI specification. It is shown that the failure loads obtained by the two experimental procedures were very close to each other. Both procedures worked well. The AISI procedure is recommended as the standard procedure.

Rotational Stiffnesses Of Semi-Rigid Baseplates, X. Feng, M. H. R. Godley, R. G. Beale

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

The paper describes a test procedure to determine the rotational stiffnesses and moment-curvature relationships of semi-rigid baseplates of cold-formed structures. The influence of the modulus of the foundation subgrade on baseplate performance is determined. Increasing the axial load applied to a baseplate is shown to increase the ultimate moment-rotation capacity of a baseplate.

Seismic Design Of Light Gauge Steel Structures: A Discussion, Reynaud Serrette

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

In a highly competitive and aggressive construction market, designers are always looking for new, proven ways to design safe, economical building structures. This is even more relevant in tract residential construction where a few dollars saved on one detail can affect who is awarded a project. In residential construction, a complete load bearing light gauge steel (LGS) system is now somewhat commonplace in the United States. Architects and engineers who once designed almost exclusively with other conventional materials are now consider LGS as an alternative. Although, it is feasible to make a direct substitution of LGS for conventional wood framing, …

Frequently Asked Questions Concerning The Aisi Base Test And The Use Of The Aisi Anchorage Equations, Roger A. Laboube, Thomas M. Murray, Joe N. Nunnery, James M. Fisher

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

The AISI Base Test Method was first introduced into the 1996 AISI Specification. Section C3.1.4 of the Specification provides a method for determining the nominal moment strength of a C- or Z- section under gravity load in the plane parallel to the web with the top flange supporting a standing seam roof system. A standing seam roof system is defined as a roof system in which the side laps between the roof panels or deck are arranged in a vertical position above the roof line, and the roof panel system is secured to the purlins by means of concealed hold …

Study On Light-Gauge Steel Roof Trusses With Rosette Connections, Pentti Makelainen, Jyrki Kesti, Olli Kaitila, Kimmo J. Sahramaa

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

This paper describes the Rosette-joining system and its possibilities in roof-truss structures in the span range of 8 to 12 meters (26 to 39 ft). The test programme that was carried out to verify the behaviour of the Rosette-joint and the thin-walled sections is described. The test results are given and analysed where they currently exist. The results are compared with values calculated according to the 1996 U.S. (AISI) [3] code supported by a distortional buckling analysis according to the Australian / New Zealand Standard (AS) [4] and FE Analysis results.

A Study On The Flexural Behavior Of Profiled Composite Beams, Gu Rok Yang, Yong Seo Hwang, Young Bong Kwon

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

An analytical study on the behavior of composite beams, which are composed of cold-formed steel sheeting and normal strength concrete, is described. An analytical method to trace the nonlinear behavior of a composite beam is developed to include the nonlinear material properties of steel sheeting, reinforcing steel bar and concrete. However, since the method is complex and tedious to use, two simple formulas for the nonlinear moment-curvature relation of the composite beam have been proposed. A simple power model, which has been originally used to predict the flexural capacity of the beam to column connections, is proposed as the first …

Factors Influencing The Strength Of Mechanical Clinching, Remo Pedreschi, Braj Sinha, Russell Davies, Rory Lennon

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

The influence of material strength and thickness, direction of load, multi-layer connections and dis-similar thicknesses of steel on the strength of mechanical clinching is considered.. Expressions to predict the strength of mechanical clinching are presented.

A Cost Based Approach To Design Of Residential Steel Roof Systems, B. Mobasher, S-Y Chen, C. Young, S. D. Rajan

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

A comprehensive system for the design of residential steel roof truss systems is presented. The research involved three distinct stages. In the first stage, components of the truss systems were tested in order to determine their member properties subjected to axial force and bending moments. Finite element simulations of these tests were carried out to further verify the, calculations obtained using the AISI-LRFD code guidelines. The AlSI-LRFD code based design curves were used for the actual design, while the laboratory experiments and the finite element results provided additional checks and verification of the AlSI values. The second stage of the …

The Local Buckling Strength Of Partially Stiffened Type 3cr12 Stainless Steel Compression Elements In Beam Flanges, G. J. Van Den Berg

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

In this study the effect of the non-linear behaviour of stainless steels on the local buckling strength of partially stiffened compression elements in beam flanges is studied. The steel under investigation is Type 3CR12 stainless steel. Lipped channels were placed back to back to form a doubly symmetric lipped I-section. The different pIasticity reduction factors suggested in the ASCE3 and South African13 stainless steel design specification for stiffened and unstiffened compression elements are used to compare experimental results with theoretical predictions. It is concluded that the ASCE3 and South African13 stainless steel design specifications overestimate the local buckling stress in …

A Non Linear Design Model For Continuous Multi-Span Light Gauge Sheeting And Members, Leopold K. Sokol

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

The calculation of profiled sheeting and members by using the post-critical stage in which a plastic hinge is originated at the internal support is possible provided that the relationships between the support moment, reaction and hinge rotation are known. There are two alternative procedures of testing for obtaining these data: double-span test or internal support test. In the second one, instead of a global behaviour, only the local relationships between the three above characteristics are determined. When calculating with the model proposed in Eurocode 3, Part 1.3, the above two different test procedures do not lead to close enough results. …

Direct Strength Prediction Of Cold-Formed Steel Members Using Numerical Elastic Buckling Solutions, Benjamin W. Schafer, Teoman Pekoz

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

Current design of cold-formed steel members is unduly complicated, Part of this complication arises from the need to perform elastic buckling calculations by hand. Also, complications occur in determining the effective width and resulting effective properties of members. Further, as cross-sections become more optimized (e.g., through the introduction of longitudinal stiffeners) both the elastic buckling and effective width calculations become markedly more complex. In order to investigate alternatives to current design a large amount of experimental data on flexural members of varying geometry is collected. The use of numerical elastic buckling solutions for the entire member, is investigated as an …

Web Crippling Of Single Web Cold Formed Steel Members Subjected To End One-Flange Loading, R. R. Gerges, R. M. Schuster

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

Results of an extensive experimental investigation of the web crippling behavior of cold formed steel C-sections are presented. This study was devoted to the End One Flange, EOF, loading case, with particular emphasis on large inside bend radius to thickness ratios, (R = ri/t). Seventy-two C-sections with R values ranging between five and 10 were tested at the University of Waterloo. Comparing the experimental results with predictions using the current North American Cold Formed Steel Design Standards, considerable underestimation was observed. Using the same model of the design expression currently used in the Canadian Standard (S136-94), and including 164 test …

Web Crippling Strength Of Members Using High-Strength Steels, Shaojie Wu, Wei-Wen Yu, Roger A. Laboube

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

A total of 148 web crippling tests were conducted using high-strength, low-ductility Structural Grade 80 of ASTM A653 steel (former ASTM A446 Grade E steel) and tests results were evaluated along with additional 114 web crippling tests which were reported in 1986 as part of a project on Design of Automotive Structural Components Using High-Strength Sheet Steels. Four loading conditions, namely End-One-Flange (EOF),lnterior-One-Flange (IOF), End-Two-Flange (ETF), and Interior-Two-Flange (ITF) conditions, were considered in the web crippling tests. Test results indicate that the tested ultimate loads for the four loading conditions were higher than the predicted loads using the AISI Specifications …

Behaviour Of Locally Buckled Singly Symmetric Columns, Ben Young, Kim J. R. Rasmussen

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

An experimental investigation into the behaviour of locally buckled cold-formed plain and lipped channel columns compressed between fixed and pinned ends is described in this paper. It is shown experimentally that local buckling does not induce overall bending of fixed-ended singly symmetric columns, as it does of pin-ended singly symmetric columns. Consequently, local buckling has fundamentally different effects on the behaviour of fixed-ended and pin-ended singly symmetric columns. In order to demonstrate this result experimentally, a series of tests was performed on plain and lipped channels brake-pressed from high strength structural steel sheets. The different effects of local buckling on …