Civil Engineering Commons^™

Softening Response Of Concrete In Direct Tension, Teresa Cintora

Theses

Due to the increased attention in nonlinear fracture mechanics and numerical methods of cementitious material, it has become necessary to have a reliable investigation of the post-peak softening response of concrete under direct uniaxial loading. But due to the brittleness of the material previous researchers have encountered great difficulty in obtaining complete data regarding the load-deformation behavior. This study uses a strain-controlled testing method and therefore the post-peak curve can be more easily obtained. Based on these results a unique formula for the normalized load vs. deformation curve has been proposed to be applied in fracture analysis applications.

Expert Systems Approach For Means Of Egress Analysis, Dimitrios N. Dontas

Theses

The use of Expert Systems has grown dramatically during the 1980's. Developed as a branch of Artificial intelligence, knowledge based Expert Systems were at first of academic interest only. With successful application of knowledge based Expert Systems to medical and other diagnostic problems, industrial and commercial use of this technique is also increasing significantly. As of 1986, fifty percent of the Fortune 500 companies are embarked in their own Expert Systems research.

A variety of knowledge based Expert Systems has been developed for the Civil Engineering design and construction industries. The applications cover a wide range of subjects, including among …

Determination Of Project Duration For Resource Constrained Projects Without Using Resource Scheduling Procedure, Rabindra Nath Karmakar

Theses

The problem addressed in this thesis is that of determining the practicability of equating measures of network and resource characteristics to the early finish date of a project which is constrained by resources. The output of standard critical path calculations along with information on resource profiles that are easy to calculate can be of use in estimating resource constrained project duration.

Twenty two different equations ( developed by Hall) were used to find the estimated project finish dates. These results were compared to the schedule resulting from the application of the heuristic rule of minimum activity float. It is shown …

Friedman's Model Of Calculating The Optimum Bid Price Using Dbase Iii Plus, Selim Uzel

Theses

The micro-computer program, BIDCALC presented in this thesis is offered as simple, practical, and proven approach to developing an effective data-based competitive bidding strategy. BIDCALC is written in dBASE III Plus programming language for MS-DOS based computers.

Main purpose of the program is to evaluate the optimum bid using the Friedman's model of Maximizing the Expected Profit. At the same time the program keeps track of necessary competitor and project information in data base files which are easily transferable to other software packages. The program is capable of generating a variety of reports in a matter of seconds.

BIDCALC is …

Column Base Plate Under Eccentric Loading, Ja-Pung Sheu

Theses

The understanding of the strength and deformational behavior of column base plates is of paramount importance in the analysis and design of pipe and pressure vessel supports. Both elastic and plastic stress analyses, using ANSYS computer program to simulate the strength and deformation of column base plates anchored over a concrete block with an eccentric load, are presented in this study. The work presented here includes the effects of bolt pretension and prying actions of stressed flexible plates.

The analytical results were benchmarked with the published test data by D.P. Thambiratnam and P. Paramasivam for the maximum longitudinal strain along …

Reliability Of Existing Bridge Inspection And Evaluation Procedures, Leroy R. Klouser

Theses

In general, bridge inspection is subjective since visual observation and the basic inspection tools cannot reveal hidden structural deterioration, such as corrosive and delaminated rebars embedded in the concrete. Based on the NJDOT SI&A report, a scale (9 to 0) is used in rating five bridge components. This approach seems reasonable, since the time span, manpower and cost are limited throughout the counties of New Jersey. On the other hand, based on the scaling system, the SI&A reports can vary depending upon the exposed surface appearance and the experience of the bridge inspector.

Water, de-icing agents, freezing and thawing cycles …

Use Of Latex Modified Concrete For Repairs And Overlays, Chen-Hoang Lo

Theses

Latex modified concrete and polymer concrete have been widely used for bridge deck overlays and crack repairs for the past decade. In recent years, many of these repaired structures were found to be defective. The causes of these failures are not clearly confirmed. Some blame the quality of the latex products while manufacturers accuse the contractors of improper placement and/or surface preparation. While most of these failures largely appeared to be debonding and delamination of the overlays, excessive cracks, possibly shrinkage cracks, were also reported in the overlaid LMC.

To evaluate the suitability of using latex modified concrete for crack …

Approximate Methods For Analysis And Design Of Channel And Tee Shaped Reinforced Concrete Columns Under Axial Compression And Biaxial Bending, Chayan Bhattacharyya

Theses

Combined Bending and Axial Compression for irregular shaped (such as L-shaped, Channel shaped, T-shaped) reinforced concrete short column is a common design problem. Current code provisions and the available design aids do not offer an insight into the determination of strength and ductility of biaxially loaded reinforced concrete columns. The reason is that the information on the behavior of irregular shaped reinforced concrete members under combined biaxial bending and axial load is not well known. They are usually overdesigned and this may cause the structure to be stiffer, which may result in loss ductility when applied to seismic regions. Thus …

Post-Cracking And Nonlinear Microcomputer Analysis In Reinforced Concrete Beams, Pedro Ricardo Munoz Arias

Theses

The main objective of this Thesis work is to study a non-linear behavior of reinforced concrete structures using the Finite Element Method and an incremental load strategy.

Bond between steel and concrete is simulated using linkage spring elements. The proposed model has a generalized crack propagation capability and it accounts for nonlinearities due to cracking and material properties.

Load-displacement relationships describing the aggregate interlock along the crack and the dowel action at the level of reinforcement are incorporated into a computer program.

A simply supported reinforced concrete beam is analyzed from zero load until failure. Contributions to the shear capacity …

Construction Labor And Productivity : Productivity Improvements, Stavros C. Nicolaou

Theses

Construction productivity has been on the decline in the last decade. Although an important factor in the nation's economy, productivity of construction labor has been given little attention over the years. A review of the literature dealing with construction was performed that revealed the importance of the declining productivity as well as the confusion among construction managers and labor leaders as to what productivity is all about and how it can be improved. It has been found also, that construction labor motivation, which is the most important factor in improving productivity, is almost nonexist. Very few construction companies employ any …

A Study Of Failure Modes In Rock Resulting From Pile Penetration, Girish Mehta

Theses

The purpose of this thesis was to physically examine the failure mode of a rock mass as a result of pile penetration. In addition, the static bearing capacity of piles bearing in rock was investigated. This was accomplished in the laboratory by performing model tests using a dynamic pile driving device.

Tests were performed using 1 inch nominal diameter model pipe piles and H-piles. Piles were driven into a simulated rock mass consisting of clay-masonry bricks. Following pile driving, the rock mass was carefully dissected and observations of the failure mode were made.

A new technique was developed to preserve …

Non-Linear Finite Element Of Analysis Of Reinforced Concrete Members, Chellathurai Jeyamohan

Theses

A finite element analysis of reinforced concrete members is used to study the initiation and propagation of cracks and the behavior at the interface of concrete and steel. The increase of concrete strength due to the biaxial compression and the shear capacity of the cracked elements are also considered in the analysis.

The results of the present analysis are compared with some available experimental data in beam tests. It has been found that the present analysis is capable of calculating the stress ( or moment ) and strain ( or deformation ) from zero load upto the ultimate load.

Construction Loan Proposal : A Model For Contractors, Saeed Ahmed

Theses

This thesis is an attempt to outline a construction loan proposal. The purpose is to provide an average contractor with an insight which could help him toward a preparation of a better proposal and better understanding of the subject matter itself.

Feasibility Of State-Of-The-Art Project Planning Techniques In Pakistan, Ahmed Mansoor Ansari

Theses

The objective of this work is two-fold:

1. Technological transfer of the best suitable state of the art techniques for implementation in the construction industry of Pakistan.

2. A vehicle intended for American readers to gain insight of the present methods of working in Pakistan.

In harmony to the first of the forestated ambitions this work covers subjects widely ranging from introducing the concept of proven scheduling techniques as CPM, PERT to the application of these techniques via advanced computer technology.

Frequently, American professionals and consulting firms are invited to participate to administer or design specialist construction projects in Pakistan. …

Computer-Aided Storm Sewer Design For Apple Macintosh, Andrea Cancalosi

Theses

The design of storm sewer systems because of its repetitive calculations lends itself to the use of computers for time-efficient solutions. The program developed designs storm sewer systems. Runoff is calculated using the Rational method. The rational method yields satisfactory results for relatively small areas and is widely used for stormwater calculations in urban areas.

Before, during or after the calculation process, the input data can be edited using a user-friendly editor incorporated into the program. Input data can be viewed by display on the screen or printed at any time while editing.

From the given input data, the program …

Failure Surface Of A Square And Rectangular Reinforced Concrete Members [Sic] Under Combined Biaxial Bending And Tension, Ravindra M. Khanapure

Theses

This thesis describes the development and use of three dimensional strength interaction diagrams of reinforced concrete sections for different loading conditions. It also gives a comprehensive overview of modes of failure surfaces and provides design aids for members subjected to biaxial bending and axial tension. This is the phenomena which is rather overlooked analytically and graphical predictions are made. The computer program provides a special tool for the analysis and fast interation of combination of loadings and moments.

Bond Behavior Of Reinforced Concrete Under Impact Loading, Abu Rayhan Md Muniruzzaman

Theses

This thesis covers experimental investigations of bond behavior of reinforced concrete specimen under impact loading. A computer assisted data acquisition system was selected for data acquisition and control. This entire electronic system involved mainly a multichannel digital oscilloscope and an IBM-AT micro computer. All specimens were tested by a modified instrumented Charpy tester assisted by the electronic system.

15 test specimen were prepared in order to perform the experimental investigations. Each 3x3x16 inch specimen was reinforced with a single deformed bar mainly 3/4" and 1/2" diameter and three catagories of concrete mainly plain, 1%, and 2% (by volume) steel fiber …

Flexural Behavior Of Portland Cement Based Composites Subjected To High Strain Rates, Edward Roland

Theses

This investigation studied the modulus of rupture and energy of rupture of mortar, concrete, and steel fiber reinforced mortar at various rates of flexural straining. The strengths of the composites were varied by changing the water cement ratios. Single point flexural loading tests were conducted on 4" x 4" x 20" specimens using a weight dropped from a height of 30" to produce the dynamic loading. Strain rates were varied between 0.1 and 1.9 per second. The inertial effects of acceleration of the specimen were taken into account.

These tests produced data that demonstrated slightly greater ratios of dynamic to …

Sorption Characteristics And Their Effects On Geotechnical Properties Of Illite, Gnanmoorthy Selvakumar

Theses

An experimental investigation of the sorption characteristics of phenol, chlorophenol and chlorobenzene on to illite and of the effect of sorption on the geotechnical properties of illite was performed. Various adsorption isotherms have been considered for the equilibrium adsorption study data. It was found that the Freundlich adsorption isotherm closely fits the experimental results. In addition, the results of desorption study indicated that the sorption process for these systems is not completely reversible.

The index properties of illite were found to be influenced by the sorption of contaminants, i.e., the Atterberg limits of illite increased in accordance with increases in …

Experimental Study Of Rectangular Reinforced Concrete Members Under Combined Biaxial Bending And Tension, Naresh B. Patel

Theses

In practice it is a very common case to have a column subjected to combined effects of axial tension and biaxial bending moments and very few efforts are done to get good design approach for such special members.

So for this purpose, experiments were carried out on rectangular shapecolumns. Rectangular shaped columns were casted in homogeneous with brackets - one on each end and at connections haunches were provided to avoid the possible end failure. The overall shape of this configuration was "H" shape. Two hydraulic jacks were used; one on either side of the columns and thus column section …

Tests On Square Reinforced Concrete Members Under Combined Biaxial Bending And Tension, Bhadresh Shah

Theses

The research reported herein studies the ultimate strength behavior for square-shaped reinforced concrete short columns under combined biaxial bending and tension that is a common design problem. The present ACI building code (ACI 318-83) (1) and design hand book (2) do not offer an insight into the determination of strength and ductility behavior of biaxially loaded reinforced concrete columns. A design equation developed by Hsu (3,4,5 ) to study the ultimate strength behavior and failure surfaces for members under these combined action was used and the computed results were compared with the present analytical results and experimental results for square-shaped …

Study Of The Effects Of Pumping Pressure On The Properties Of Fresh Concrete, Dinesh Vithal Kenkre

Theses

This thesis has a two-fold objective. One, to develop a suitable testing apparatus in the labaratory to simulate the effect of field pumping of concrete and two, to conduct some preliminary tests to investigate the feasibility of the testing apparatus.

Pumping of concrete has been practiced in the U.S.A. since 1930. The behaviour of concrete in a pipeline has not been studied in much detail while development in the pumping technology raced ahead of the research in this field. Previous studies done in this field have clearly indicated the need for a laboratory simulation of pumping process in order that …

Systems Building Theory Application Within The Residential Housing Construction Market, Gary Alexander Newhard

Theses

The primary purpose of this report is to introduce the economical value in utilizing certain "systems building" applications. In this report I focus on integrated system methodologies that encourage residential building economy and submit such systems as a viable alternative to traditional labor intensive housing construction. The consumer market that could be particularly enhanced by these systems ranges from low income to middle income and the by-product would be classified as "affordable" housing.

This report focuses on the New Jersey real estate market and presents certain prefabricated housing systems as an economical means of meeting the large demand for residential …

Fracture Energy And Tensile Behavior Of Concrete, Wen-Jinn Chiou

Theses

Fracture behavior of concrete has been a subject of investigation for the past two decades. The need of understanding the complete tensile response of concrete is absolutely essential for theoretical modelling as well as design application of plain concrete structures.

In this study, attempts were made to investigate the validity of two important fracture parameters, namely, the fracture energy and the critical crack tip opening displacement. Three types of test specimen, dog- bone shaped tension specimen, notched beam and compact tension specimen, were investigated. These tests were conducted using the closed-loop MTS 810 strain-controlled testing system. For the uniaxial tension …

Modelling Of Pile Load Tests In Weak Rock, Daniel Walter Caruso

Theses

The purpose of this thesis was to investigate the loss of load capacity of relaxed pile groups driven into weak bedrock. This was accomplished in the laboratory using a dynamic driving apparatus equipped with a static load testing system. The static load testing system applied loads hydraulically, and the load settlement behavior was monitored using an electronic load cell and a linear variable differential transducer (LVDT).

Tests were performed using 1" diameter steel pipe piles driven in a five pile group pattern at spacings of two diameters and four diameters. Piles were driven into a simulated rock mass consisting of …

Pozzolanic Admixtures In Concrete Mix, Ronghao Chen

Theses

Fly ash and condensed silica fume are two main mineral pozzolanic admixtures in portland cement concrete. The increasing use of the fly ash in concrete projects and concrete products during the past 3O years and condensed silica fume in several projects during the past 1O years indicates a greater acceptance of them as the mineral pozzolanic admixtures in concrete. Although the engineers are of some identical views in using these industrial byproducts in concrete projects, there are different views on how the behavior and utilization of fly ash con-crete and condensed silica fume concrete since the byproducts are not the …

Computer Application Of Project Planning And Scheduling With Cpm, Mohamed Tarek Abdel-Aziz

Theses

Scheduling is one of the most important tools for project management and control, and the CPM is one of the techniques used in project scheduling.

The primary objective of this thesis is to develop a CPM computer package using a microcomputer. The package is constituted in Basic (Applesoft Basic) for use on Apple II Plus, IIe or IIc.

The package is intended to be available to users without sufficient knowledge about computer. And it consists of two computer programs. The first computer program is the CPM-I which schedules project activities with unlimited resources. The second computer program is the CPM-II …

Similitude Analysis Of Model Experiments Of Piles Driven To Rock, George Nicou Georghoudes

Theses

This thesis investigates the similitude requirements for the Dynamic Pile Driving Apparatus in the New Jersey Institute of Technology Laboratory. The apparatus is being used to perform model tests to study bearing stratum fracturing caused by driving pile groups to weak rock.

Two approaches were used to establish similitude between the model and actual field conditions. The first approach utilizes dimensional analysis to develop a relationship between the energy delivered to the rock mass by the pile and the unit length. The second approach proposes a procedure to establish an empirical relationship between the threshold energy to fracture the rock …

Use Of Clay As A Landfill Liner, Mayur B. Desai

Theses

The purpose of this thesis is to study the factors affecting efficient functioning of clay material for containment of landfill materials. The study of liner-leacheate interaction is done from the consolidation and vane shear tests on various clays having different activities, and chemicals that are typically found in a municipal solid waste leachate and a leachate collected from an active landfill.

An effort was made to study the use of Atterberg limits to predict the suitability of a clay as a landfill liner for a given waste environment. The study indicates that there is a decrease in permeability of bentonite …

Effects Of Adhesion On The Active Pressure Exerted On A Retaining Wall, Thomas G. Gallagher

Theses

This paper investigated the effect of adhesion on the active pressure behind a retaining wall. No equation existed to solve for the active pressure for a sloped backfill that also takes into consideration cohesive and adhesive forces on a failure wedge. The trial—wedge solution(Culmann method) considers these parameters, but since it is a trial and error method it takes up too much time to solve. A shorter solution is desirable. An equation for the active pressure in terms of ρ(angle between horizontal and failure plane) was derived. A closed form solution for earth pressure was developed by setting the derivative …