Civil and Environmental Engineering Commons^™

Comparison Of The Properties Of Portland Cement And Portland-Limestone Cement, Alex Lyatonga Mrema

Tanzania Journal of Engineering and Technology (TJET)

A study was made in a cement factory in Dar es Salaam, Tanzania, where Ordinary Portland Cement (CEM I 42.5N) and Portland-limestone cement (PLC) which has the brand name Twiga Cement Extra (CEM II/A-L/32.5R) are produced and conforming to the Tanzania Standard TZS 727 (Part1): 2002, which is equivalent to EN 197 published by the committee for European normalization (CEN). A comparison was made between the two types of cements in terms of physical, chemical and mechanical properties. It was found out that they all complied with the standards, that there was no significant difference in their setting times and …

Best Practices For Dealing With Price Volatility In Utah Commercial Construction, Justin Earl Weidman

Theses and Dissertations

In the commercial construction industry, the problem of price volatility as it pertains to materials and labor is a consistent problem. The changing instability of market conditions presents a challenge for construction companies to accurately estimate and complete projects within budget. This volatility can lead to higher costs and more risk to suppliers, contractors, and owners which can cause financial distress for all parties involved in the construction process. As lump sum contracts are typically being used on many projects, the owners seem to have the upper hand and are forcing contractors to honor lump sum contracts even when prices …

Validation Of Methods For Adjusting Construction Cost Estimates By Project Location, Adam Martinez

Civil Engineering ETDs

Location factors are used to adjust conceptual cost estimates by project location. Presently, the construction industry has adopted a simple, proximity-based interpolation method which uses the “nearest neighbor” location factor to estimate unknown location factors. Although this approach is widely accepted, its validity has not been statistically substantiated. This study assessed the current method of adjusting conceptual cost estimates by project location. An evaluation of 14 alternative spatial estimation methods was also conducted. These methods were based on different approaches for combining 4 criteria: proximity, state boundary, home value, and income. This study used the 2006 RSMeans city cost index …

Groundwater Stress And Vulnerability In Rural Coastal Aquifers Of The Kalpitiya Peninsula, Sri Lanka, D. Jayasekera, Jagath J. Kaluarachchi, K. Villholth

Civil and Environmental Engineering Faculty Publications

Rural coastal aquifers are undergoing rapid changes due to increasing population, high water demand with expanding agricultural and domestic uses, and seawater intrusion due to unmanaged water pumping. The combined impact of these activities is the deterioration of groundwater quality, public health concerns, and unsustainable water demands. The Kalpitiya peninsula located northwest of Sri Lanka is one area undergoing such changes. This land area is limited and surrounded almost completely by sea and lagoon. This study consists of groundwater sampling and analysis, and vulnerability assessment using the DRASTIC method. The results reveal that the peninsula is experiencing multiple threats due …

A Study On Repairing Internal Defects Inside Concrete Using The Electrochemical Deposition Method, Weichung Yeih, Hui-Mi Hsu, Jiang-Jhy Chang, Chi-Che Hung, Rang Huang

Journal of Marine Science and Technology–Taiwan

In this paper, the feasibility of repairing internal defects inside concrete using the electrochemical deposition method is investigated. Various amounts of the air entrance agent (AEA) were added into fresh concrete to produce small air bubbles. Zinc sulfate was used as the electrolyte for the electrochemical deposition method. The dry unit-weight test, compressive strength test, splitting tensile strength test, four-probe electric resistivity, water absorption percentage test, open circuit potential test, scanning electronic microscope (SEM) and X-ray diffraction are carried out to investigate the repair results. Results show that the electrochemical deposition method is a promising rehabilitation method when internal defects …

Developing An Analytical Model For The Optimal Capital Structure Of The Building Company, Lung-Ken Tsai, Hui-Ping Tserng, S. Ping Ho, Chiu-Wei Sung, Yeh-Shou Chou

Journal of Marine Science and Technology–Taiwan

The characteristics and accounting principles of the building industry is different from those of other industries, so few studies have discussed the capital structure of the building industry. In this paper, the grey system theory and Pearson correlation analysis are used to study the capital structure (debt ratio) of building companies and its relationship with the company’s tax rate, non-debt tax shield, and operational risk, respectively. The results show that for building companies, non-debt tax shield has a positive correlation with the capital structure, whereas the operational risk has a very low correlation with the capital structure. The aforementioned results …

Relative Importance Of Fire Resistance Performance Of Partition Walls, Ming-Chin Ho, Ming-Ju Tsai

Journal of Marine Science and Technology–Taiwan

The fire performance of partitions is influenced by the thickness, type, combustibility level of panel material, type of filling material and frame. However, realizing the importance of these parameters is not of enough help for interior designers. They need more quantitative information of the relative importance of the parameters so that they can select materials with cost consideration. Experiments were thus designed and analyzed by the Taguchi experimental design analysis method for it is good to determine the effect of each parameter especially as the number of parameters is large. Our data and analysis show that the thickness of panel …

Probabilistic Assessment Of Seismic Drift Demands For Frame Structures In Near-Fault Regions, Jan Tysh-Shang, Lin Chiung-Yueh, Wu Chun-Wei

Journal of Marine Science and Technology–Taiwan

The purpose of this paper is to provide engineers with a rapid procedure to assess the maximum inter-story drift for generic moment-resisting frame (GMRF) structures in nearfault regions. In this procedure, the maximum inter-story drift demand of a structure can be evaluated by starting from the median value of elastic spectral displacement at the first period of the structure, and then amplifying it with some modification factors. Statistical parameters (medians and dispersions) of the distributions of these factors are obtained by performing linear, and nonlinear, dynamic simulations on codecompliant steel GMRF structures, to near-fault ground motions during Taiwan’s Chi-Chi earthquake …

The Influence Of Broken Cables On The Structural Behavior Of Long-Span Cable-Stayed Bridges, Chin-Sheng Kao, Chang-Huan Kou

Journal of Marine Science and Technology–Taiwan

The influence of broken cables on the structural behavior of long-span cable-stayed bridges is examined considering all the nonlinear characteristics of a long-span cable-stayed bridge. The results show the influences of the broken cable on the structural behavior, such as the internal force, displacement, and the ultimate load-bearing capacity, are clear when an outside cable breaks. The results of the present study should assist in deciding when to replace cables in long-span cablestayed bridges.

Genetic Algorithm-Based Chaos Clustering Approach For Nonlinear Optimization, Min-Yuan Cheng, Kuo-Yu Huang

Journal of Marine Science and Technology–Taiwan

In this paper, a n-dimension convergence algorithm was employed to track the potential trend of evolution in traditional genetic algorithm (GA) by K-means clustering technique. And, chaotic algorithm was exploited to prevent the new approach from premature. By means of the proposed approach, not only the basic search capability was maintained but also the flexibility and efficiency of parametric modeling were improved. The main purpose of the paper is to demonstrate how the GA optimizer can be improved by incorporating a hybridization strategy. Experimental studies revealed that the hybrid chaotic approach with genetic algorithm (CGA) procedure could produce much more …

Numerical Solutions Of Coastal Morphodynamic Evolution For Complex Topography, Chiang Yun-Chih, Hsiao Sung-Shan, Lin Ming-Chung

Journal of Marine Science and Technology–Taiwan

Numerical modeling of coastal morphodynamic evolution is a powerful tool for the planning and design of coastal engineering. The coastal morphological modeling system is based on the sediment conservation law, which couples modules for waves, wave-driven currents, and sediment transport rates. The numerical scheme for the sediment conservation law and nonlinear coupling between these modules can lead to dispersions, diffusions, spurious oscillations and stability problems that are still not well developed. In this paper, the bedslope updating techniques, oscillation removal schemes, and 2-step, 3-time-level temporal discretization are employed to avoid oscillations and improve the stability of the coastal morphological model …

Revisited To The Relationship Between The Free And Total Chloride Diffusivity In Concrete, Ming-Te Liang, Ran Huang, Hao-Yuan Jheng

Journal of Marine Science and Technology–Taiwan

The main purpose of this paper is provided the theoretical elucidation and parameter investigation for the experimental results performed by Lu et al. [Relationship between the free and total chloride diffusivity in concrete, Cement and Concrete Research, 32(2) 323~326 (2002)]. The analytical solution of Fick’s second law of linear diffusion in a semi-infinite quasi-homogeneous and isotropic concrete with initial and boundary conditions is used to curve fitting the experimental results and to find the relevant parameters such as the total and free chloride concentrations and diffusivities. The total chloride diffusivity is 2.8 times the free one. It seems plausible to …

Natural Fibers And Fiberglass: A Technical And Economic Comparison, Justin Andrew Zsiros

Theses and Dissertations

Natural fibers have received attention in recent years because of their minimal environmental impact, reasonably good properties, and low cost. There is a wide variety of natural fibers suitable for composite applications, the most common of which is flax. Flax has advantages in tensile strength, light weight, and low cost over other natural fibers. As with other natural and synthetic fibers, flax is used to reinforce both thermoset and thermoplastic matrices. When flax is used in thermoplastic matrices, polypropylene and polyethylene are the main resins used. Although at first glance flax may seem to be a cheaper alternative to fiberglass, …

Numerical Analysis Of The Effectiveness Of Limited Width Gravel Backfills In Increasing Lateral Passive Resistance, Mo'oud Nasr

Theses and Dissertations

Two series of static full-scale lateral pile cap tests were conducted on pile caps with different aspect ratios, with full width (homogeneous) and limited width backfill conditions involving loose sand and dense gravel. The limited width backfills were constructed by placing a relatively narrow zone (3 to 6 ft (0.91 to 1.83 m)) of higher density gravel material adjacent to the cap with loose sand beyond the gravel zone. Test results indicated that large increases in lateral passive resistance could be expected for limited width backfills. The main focus of this study is to assess the contribution of plane strain …

East Bay Energy Consortium Meeting Agenda, June 7, 2010, East Bay Energy Consortium

East Bay Energy Consortium Meeting Agenda

No abstract provided.

The Relevance Of Teaching Traditional Measurement Techniques To Undergraduate Quantity Surveying Students., Fiacra P. Mcdonnell

Articles

Measurement of quantities is a core skill which must be inherent in all graduates from Quantity Surveying courses. Many students find this subject difficult to grasp, and the learning experience can be problematic especially in the first semester of first year. This is not unique to measurement as in many cases first year students are in the process of adapting to a new stage in their life, along with attempting to master many new subjects (Cottrell, 2008). This is reinforced by Johnston (2010) who highlights the many challenges being experienced by first year students and observes that “ entering first …

Table 6.04, Mark E. Shaurette

Supplementary Content for <em>Demolition: Practices, Technology, and Management</em> <br>(ISBN 978-1-55753-567-2)

No abstract provided.

Simplified Procedures For Seismic Analysis And Design Of Piers And Wharves In Marine Oil And Lng Terminals, Rakesh K. Goel

Civil and Environmental Engineering

No abstract provided.

Static And Fatigue Bond Characteristics Of Frp Rebars Embedded In Fiber-Reinforced Concrete, Huanzi Wang, Abdeldjelil Belarbi

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

A research project was initiated to develop a nonferrous hybrid reinforcement system for concrete bridge decks by using continuous fiber-reinforced polymer (FRP) rebars and discrete randomly distributed polypropylene fibers. This hybrid system may eliminate problems related to the corrosion of steel reinforcement while providing requisite strength, stiffness, and desired ductility, which are shortcomings of FRP reinforcing system in plain concrete. This article presents the results of a part of this research program, i.e., the bond behaviors of this hybrid reinforcing system under monotonic and fatigue loading. Test results indicate that the addition of polypropylene fibers does not increase the ultimate …

Impact Of Preferential Flow Paths On Alluvial Groundwater Flow Patterns And Phosphorus Transport, Derek M. Heeren, Ronald B. Miller, Garey A. Fox, Daniel E. Storm, Aaron R. Mittelstet, Chad J. Penn

Department of Agricultural and Biological Systems Engineering: Faculty Publications

While surface runoff is considered to be the primary transport mechanism for phosphorus (P), subsurface transport through coarse subsoil to gravel bed streams may be significant and represent a source of P not alleviated by current conservation practices (e.g., riparian buffers). Previous research has documented P transport in a preferential flow path (PFP) identified as a buried gravel bar. It is hypothesized that PFPs, if connected to the soil surface, provide a rapid and efficient method of transporting P, and that these alluvial features are transient storage zones for nutrients, acting as a sink during high flow and a source …

Assessment Of Kentucky's Historic Truss Bridges, Lenahan O’Connell, Ted H. Grossardt, John Ripy

Kentucky Transportation Center Research Report

This study created an information base to improve decisions about the replacement or rehabilitation of historic truss bridges. During the first phase of the research, information on the history and design of the 109 bridges in the study was assembled. With the assistance of historic preservation professionals, 75 of those bridges were selected for further study for their potential for rehabilitation. During the second phase, the KTC research team, engineers from the KYTC bridge division, and 12 highway district engineers, who are responsible for the day-to-day care and maintenance of the bridges, evaluated the condition and functional context of the …

Travel Time Based Congestion Measures For Freeway Corridors, Mei Chen

Kentucky Transportation Center Research Report

Travel time based mobility measures have been increasingly used in highway performance analyses. Among them, Travel Time Index (TTI), Planning Time Index (PTI), percentage of travel under congestion (PTC), and buffer index (BI)have been identified as measures of particular interests in Kentucky. The objectives of this study are: (1) Calculate TTI, PTI, PTC, and BI for freeways within the TRIMARC coverage; and (2) Explore potential correlation between the reliability measures and incident characteristics (e.g., number of incidents, duration, severity, etc.). These analyses were performed for the years 2006-8 for each monitored segment and freeway corridor as well as for the …

Foundation Design For High Tension Cable Guardrails, John R. Rohde, Ryan J. Terpsma, Ling Zhu

Nebraska Department of Transportation: Research Reports

No abstract provided.

Developments In Intelligent Monitoring Of Concrete Structures, T. M. Chrisp, G. Starrs, W. J. Mccarter, E. H. Owens, S. V. Nanukuttan, Niall Holmes, L. Basheer

Conference papers

Deterioration in concrete comprises an initiation period and a propagation period. The initiation period is characterised by changes that occur within the concrete in response to the exposure environment and continues until a stage is reached when damage begins to propagate. The propagation period begins at a point in time defined when a particular event occurs (e.g. loss of steel passivity due to chloride ingress) and continues until a specified limit state is reached. The initiation and propagation stages of a deterioration process result from a complex interaction of physical, chemical and electrochemical phenomena. Prediction of the field performance of …

Review Of State Laws And Practices For Disposition Of Re-Aligned Or Bypassed Segments And Associated Row, Lenahan O'Connell, Ted Grossardt

Kentucky Transportation Center Research Report

This study identified the laws and practices of 11 state DOTs in regard to the transfer of responsibility for re-aligned or bypassed state highway system roads to local jurisdictions - usually cities or counties. Each state's approach to such transfers was identified by obtaining and analyzing the relevant state statutes and then conducting telephone interviews with strategically placed individuals at the associated DOT. Four states require local approval before the state can abandon a road. These four have a policy of obtaining written consent for the transfer of responsibility for maintenance and do so most often prior to construction of …

Roadway Related Tort Liability And Risk Management, Kenneth R. Agent

Kentucky Transportation Center Research Report

This workbook provides government employees background information related to tort liability and risk management. Past experience with lawsuits against government entities are summarized. The reasons for the lawsuits and results are analyzed. The objective is to provide an understanding of the basis for past claims so the number of future claims and awards can be reduced. This will result in the ultimate objective of reducing highway crashes.

Based on the results of the data analysis and the review of the background material, recommendations are made for consideration. Many of the recommendations deal with various types of documentation.

Improving Intersection Design Practices Final Report - Phase I, Nikiforos Stamatiadis, Adam Kirk

Kentucky Transportation Center Research Report

The purpose of this report is to document the development of the Intersection Design Alternative Tool (IDAT) developed for the Kentucky Transportation Cabinet. IDAT provides an automated objective design and evaluation approach of 14 alternative intersection designs to assist in the conceptual design of at grade intersections. The tool evaluates intersection operations, safety performance, bicycle/pedestrian accommodation and has the ability to assist access management implementation.

In-Situ Monitoring And Testing Of Ibrc Bridges In Wisconsin, Christopher Foley, Baolin Wan, Carl Schneeman, Kristine Barnes, Jordan Komp, Junshan Liu, Andrew Smith

Transportation Reports with the Wisconsin Department of Transportation

This study examines two highway bridges constructed using novel fiber-reinforced polymer (FRP) composite stay-in-place formwork and an FRP grillage reinforcement system. Both bridge superstructures rely on the FRP components as bridge deck reinforcement. These bridges were monitored in-situ for a period of five years. The monitoring included a series of in-situ load test as well as non-destructive evaluation (NDE). Laboratory investigations accompanied and guided the load testing and NDE implemented. Finite element simulations were employed to evaluate the likely causes of premature deck cracking seen in the traditionally-constructed bridge and the FRP-component superstructures. The study identifies sources of potential deterioration, …

Offset Right-Turn Lanes For Improved Intersection Sight Distance, Karen Schurr, Timothy J. Foss Jr.

Nebraska Department of Transportation: Research Reports

No abstract provided.

Scale Model Shake Table Testing Of Underground Structures In Soft Clay, Victor A. Crosariol

Master's Theses

Underground structures perform an important role in transportation systems in many seismically active regions around the world, but empirical data regarding the seismic behavior of these structures is limited. This research works towards filling that empirical gap through the use of scale model shake table testing. Underground seismic soil-structure interaction (USSSI) effects were investigated for a stiff rectangular tunnel cross-section embedded within soft clay. San Francisco Young Bay Mud was used as a prototype soil for developing a scale model soil mixture consisting of kaolinite, bentonite, class C fly ash, and water. A single cell Bay Area Rapid Transit (BART) …