Civil Engineering Commons^™

Study Of Water Permeability Of Lightweight Concrete, Xiaoxiao Xu, Haibin Yang, Hongzhi Cui, Zitao Lin, Tommy Yiu Lo

International Conference on Durability of Concrete Structures

The relationship between water permeability and different levels of the tested layers from the top surface to the bottom surface of the lightweight concrete specimens is determined in this study. It is beneficial to develop the design criteria for a durable lightweight concrete. The water permeability coefficient K of the samples was determined by water permeability test using GWT. It is found that the water permeability coefficient K of the three layers in each set of samples tends to decrease as the level of the tested from the top surface increase. Larger Rebound Number and higher density in the bottom …

Impact Of Extreme Summer Temperatures On Bridge Structures, Ryan Hagedorn

Graduate Theses and Dissertations

Climate change and its effect on weather in the United States is a well-documented phenomenon. In particular, extreme heat waves have become more intense, more frequent, and longer lasting, especially in the southern United States. As with much of America’s transportation infrastructure, prestressed concrete bridge girders experience the effects of these heat waves. Uneven heating of optimized bridge girder sections results in large non-linear temperature gradients. In this study, temperature was monitored in three different AASHTO I-girders to determine the vertical and transverse temperature gradients in a pre-deck placement condition. It was determined that the current design standard, which uses …

Rehabilitation And Strengthening Of Reinforced Concrete Members Using A Fiber Reinforced Cementitious Matrix Composite, Zena Riyadh Aljazaeri

Doctoral Dissertations

“Externally bonded fiber reinforced cementitious matrix (FRCM) for structural members was tested and evaluated as a new class of composite material for repairing and strengthening infrastructures. In comparison with fiber reinforced polymer (FRP) composites, FRCM composite has a superior high temperature resistance and great compatibility with concrete substrates. Experimental investigation is ongoing in the United States to evaluate the structural and durability performance of FRCM composite to be implemented in field applications. This experimental program consisted of testing 12 strengthened reinforced concrete (RC) beams to study the fatigue and flexure performance under environmental exposure and sustained stress, 10 strengthened RC …

Effect Of Fly Ash Fortification In The Manufacture Process Of Making Concrete Towards Characteristics Of Concrete In Sulfuric Acid Solution, Asep Handaya Saputra, Muhammad Shohibi, Masatoshi Kubouchi

Makara Journal of Technology

Fly ash is a silica or alumino silica material that can be used as a constituent of cement in the concrete manufacturing process. Utilization of fly ash aims to improve durability and minimize the reduction of concrete’s compressive strength exposed to an acidic environment, which can be achieved through the pozzolanic reaction of fly ash with Ca(OH)2 within concrete. The reduced content of Ca(OH)2 through pozzolanic reaction will minimize the tendency of ettringite formation (compounds that cause deterioration and decrease the compressive strength of concrete). In order to determine the relation between fly ash replenishment into concrete with concrete’s characteristics …

Investigation Into Mechanisms And Mitigation Of Alkali-Silica Reaction In Sustainable Portland Cement Concrete Containing Recycled Glass Materials, Kaveh Afshinnia

All Dissertations

A significant portion of recycled glass from municipal waste streams is not found to be suitable for reuse as cullet in the production of new glass containers, and as a result it is disposed in landfills. One of the appropriate ways to reduce the disposal of waste glass in landfills is by using it in portland cement concrete as an aggregate material and/or supplementary cementitious material to replace portion of portland cement. The high silica content of the soda glass (approximately 70%) can potentially behave as a pozzolanic material when finely ground, which may enhance the mechanical and durability properties …

Reducing The Porosity And Sealing Cracks By Using Crystalline Admixture In Conventional Concrete, Visar Krelani, Liberato Ferrara

UBT International Conference

There is a continuous increase of quality on civil engineering materials in developed countries and parallel increase of need for new constructions in developing countries. Professional community should propose solutions for the durability that can resist in different severe environments. The most important factor that can affect concrete durability is represented by the pore distribution. Transport properties can take place through the porous network inside the cementitious composites and the aggregates interface, permitting the ingress of aggressive agents damaging concrete function intrinsically as a material and the well-functioning of the entire structure. The use of a crystalline admixture during the …

Feasibility Study: The Evaluation Of Polymer Coatings To Prevent Weathering Of Weak Rocks, Lauren Distler

Senior Honors Projects, 2010-2019

The weathering and erosion of weak rocks along roadways can cause dangerous and potentially fatal rockfalls.   Various slope stabilization methods exist, but each presents a set of challenges and trade-offs.   The focus of the project is to understand the feasibility of utilizing of a polymerbased slope stabilization technique. Rock samples were collected along US Route 33 in Virginia and West Virginia, and preliminary tests were conducted to evaluate the absorption of water (% mass) and durability. The study evaluates three polymer options in regard to the following criteria: adhesion to rock, layer thickness, semi-permeability, insolubility, and non-toxicity. The polymer selection …

Surface Treatment Of Cement-Based Materials With Nanosio2, Pengkun Hou, Xin Cheng, Jueshi Qian, Surendra P. Shah

International Conference on Durability of Concrete Structures

A dense surface structure of cement-based material is favorable for its resistance to the impacts of environment. In this work, effectiveness and mechanisms of the surface treatment of cement-based materials with nanoSiO₂ of different states, that is, colloidal nanoSiO₂ (CNS) and the in situ formed nanoSiO₂ gel through the hydrolysis of its precursor of tetraethoxysilane (TEOS), by brushing and soaking techniques, were investigated. Results showed that both CNS and TEOS are capable of reducing the liquid and gaseous transport properties of hardened cement-based materials, although at a different extent. It revealed that the pozzolanic reactivity and the …

Forecasting Corrosion Of Steel In Concrete Introducing Chloride Threshold Dependence On Steel Potential, Andrea Nathalie Sanchez

USF Tampa Graduate Theses and Dissertations

Corrosion initiates in reinforced concrete structures exposed to marine environments when the chloride ion concentration at the surface of an embedded steel reinforcing bar exceeds the chloride corrosion threshold (CT) value. The value of CT is generally assumed to have a conservative fixed value ranging from 0.2% to - 0.5 % of chloride ions by weight of cement. However, extensive experimental investigations confirmed that CT is not a fixed value and that the value of CT depends on many variables. Among those, the potential of passive steel embedded in concrete is a key influential factor on the value of CT …

Durability Studies On Native Soil-Based Controlled Low Strength Materials, Bhaskar Chittoori

Civil Engineering Faculty Publications and Presentations

The Integrated Pipeline Project (IPL) is a collaborative effort between the Tarrant Regional Water District (TRWD) and Dallas Water Utilities (DWU), which bring additional water supplies to the Dallas / Fort Worth area. As part of a sustainability initiative, several studies were conducted to assess the reuse potential of excavated materials along the IPL project. One of these studies involved using the excavated material as an ingredient in Controlled Low Strength Material, often known as CLSM or flowable fill. This flowable fill can be used as bedding and haunch material in pipeline construction. These CLSMs meet the specifications in the …

Deformation And Shear Behaviors Of Weathered Compacted Shale, Xu Zhang

Theses and Dissertations--Civil Engineering

As an abundant sedimentary rock, shale is widely used as construction material around the world. However, shale is a fissile and laminated material and is therefore subject to deterioration due to environmental and chemical forces (i.e., weathering), which is possible to cause high maintenance cost on associated structures and failures of earth slopes and embankments. However, currently, there is lack of efficient method to monitor the weathering process of shale. This thesis uses several shale samples collected from the commonwealth of Kentucky to study the deformation and shear behaviors of weathered compacted shale. A new electrical approach was developed to …

Increasing The Durability Of Piezoelectric Impact-Based Micro Wind Generator In Real Application, Hyun Jun Jung, Yooseob Song, Seong Kwang Hong, Chan Ho Yang, Sung Joo Hwang, Tae Hyun Sung

Civil Engineering Faculty Publications

The purpose of this study is to increase the durability of piezoelectric impact-based micro wind generator (PIMWG) in real application. Using new PIMWG design, numerical simulation, and experimental comparison analysis, we improved the durability of PIMWGs in real application. The experimental results show that the optimized PIMWG generated 2.4 mW (RMS value), and it did not crack within 40 h. In this study, we improved the durability of PIMWGs for real application.

Experimental And Numerical Investigations On Bond Durability Of Cfrp Strengthened Concrete Members Subjected To Environmental Exposure, Haider Al-Jelawy

Electronic Theses and Dissertations

Fiber reinforced polymer (FRP) composites have become an attractive alternative to conventional methods for external-strengthening of civil infrastructure, particularly as applied to flexural strengthening of reinforced concrete (RC) members. However, durability of the bond between FRP composite and concrete has shown degradation under some aggressive environments. Although numerous studies have been conducted on concrete members strengthened with FRP composites, most of those studies have focused on the degradation of FRP material itself, relatively few on bond behavior under repeated mechanical and environmental loading. This thesis investigates bond durability under accelerated environmental conditioning of two FRP systems commonly employed in civil …

Effect Of Localized Corrosion Of Steel On Chloride-Induced Concrete Cover Cracking In Reinforced Concrete Structures, Ezeddin Rafaa Busba

USF Tampa Graduate Theses and Dissertations

Abstract: Concrete cover cracking due to reinforcement corrosion is widely accepted as a limit-state indicator in defining the end of functional service life for existing reinforced concrete (RC) structures undergoing corrosion. Many of the currently available durability prediction models are incapable of providing realistic estimates of remaining service lives of RC structures beyond the corrosion initiation point. Therefore, the need to incorporate the length of the corrosion propagation stage in a comprehensive durability prediction approach has recently received much research attention. Previous research focus however was mostly limited to the case of uniformly corroding reinforcement with only few studies addressing …

Durability Of Reinforced Concrete Incorporating Crushed Waste Brick As Coarse Aggregate, Matthew Adamson

All Theses

Using crushed bricks as aggregates in concrete is of particular interest to preserve natural aggregate sources as well as to reduce waste, as it has been estimated that 10% to 30% of all waste in landfills in the united States comes from construction and demolition wastes. By recycling some of these wastes, the sustainability of a project can be improved. However, it is important concrete incorporating these wastes is as durable or more durable then conventional concrete, or will it have a shorter service life. Durability of concrete is its ability to resist deterioration from its external environment such as …

Engineering Performance Of Polymer Amended Soils, Gary E. Welling

Master's Theses

A laboratory test program was undertaken to evaluate a series of engineering properties over a range of soil types; amendment types and addition rates; and moisture contents to enhance understanding of the engineering significance of polymer amendment. Four soils were manufactured and tested with varying ranges of fines and plasticity. A proprietary elastic copolymer was tested at addition rates of 0.5% to 2.5% (dry weight basis). Cement was tested at addition rates of 1% to 4%. Lime was tested at an 8% addition rate. Water addition rates ranged from 4% dry of optimum to 4% wet of optimum. Engineering properties …

Effects Of High Volume Fly Ash And Powder Activators On Plastic And Hardened Concrete Properties, Drew Alexander Davis

Masters Theses

This study was performed to examine the effects of high volumes of Class C fly ash modified by powder activators upon the plastic and hardened properties of concrete. In a companion study, five Missouri area cements and five Class C fly ashes were examined for incompatibilities, with the most and least reactive combinations being scaled up to full scale concrete testing. Two baseline concrete mixtures were examined, the only difference in mixtures being the sources of portland cement and fly ash. Fly ash replacement was examined at 50% and 70% replacement (by total cementitious mass). Three powder activators were used …

Development Of Internally Cured Concrete For Increased Service Life, John Schlitter, Ryan Henkensiefken, Javier Castro, Kambiz Raoufi, Jason Weiss, Tommy Nantung

JTRP Technical Reports

Higher strength, lower water to cement ratio (w/c) concrete has been advocated over the last two decades due to its increased strength and reduced permeability. The lower w/c of these concretes makes them susceptible to autogenous shrinkage. This autogenous shrinkage can be significant and can be a contributing factor to early age cracking. Internal curing was investigated as a potential method to improve the durability of concrete pavements and bridge decks. Prewetted lightweight aggregate was used to supply water to the hydrating cement paste. This additional water can counteract the hindered strength development, suspended hydration, autogenous shrinkage, and early age …

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 …

Developments In Monitoring Techniques For Durability Assessment Of Cover-Zone Concrete, W.J. Mccarter, T. M. Chrisp, G. Starrs, Niall Holmes, L. Basheer, M. Basheer, S. V. Nanukuttan

Conference papers

This paper outlines developments in the use of an embedded multi-electrode sensor to study the response of the cover-zone (surface 50mm) to the changing ambient environment. The sensor enables the measurement of the spatial and temporal distribution of the electrical properties of concrete and temperature within the cover-zone thereby allowing an integrated assessment of cover-zone concrete performance. Both laboratory and field results are presented to highlight the information that can be obtained from embedded sensors. When exposed to the natural environment, the temperature dependence of the electrical response is highlighted and standardization protocols are developed to account for this effect. …

On The Use Of Polyurethane Matrix Carbon Fiber Composites For Strengthening Concrete Structures, Zachary Haber

Electronic Theses and Dissertations

Fiber-reinforced polymer (FRP) composite materials have effectively been used in numerous reinforced concrete civil infrastructure strengthening projects. Although a significant body of knowledge has been established for epoxy matrix carbon FRPs and epoxy adhesives, there is still a need to investigate other matrices and adhesive types. One such matrix/adhesive type yet to be heavily researched for infrastructure application is polyurethane. This thesis investigates use of polyurethane matrix carbon fiber composites for strengthening reinforced concrete civil infrastructure. Investigations on mirco- and macro-mechanical composite performance, strengthened member flexural performance, and bond durability under environmental conditioning will be presented. Results indicate that polyurethane …

Performance-Based Testing Methodology For Concrete Durability, Niall Holmes, P. A.Muhammed Basheer, Sreejith Nanukuttan, Lulu Basheer

Reports

This report presents an overview of performance based testing methodology for concrete durability and work currently underway jointly at Queens University Belfast and Heriot Watt University, Edinburgh, to undertake this research under a EPSRC funded project (EP/G02152X/1).

EN206-1 superseded BS 5328 on 1^st December 2003 and allows designers and producers to use a wide range of cements and aggregate types for a variety of exposure conditions. In this new standard, the durability of concrete is specified in terms of the constituent materials of concrete, properties of fresh and hardened concrete, limitations for concrete composition, specification of concrete, delivery of …

Flexural Mechanical Durability Of Concrete Beams Strengthened By Externally Bonded Carbon Fiber Reinforced Polymer Sheets, Michael Olka

Electronic Theses and Dissertations

About 77,600 bridges throughout the United States in the Federal Highway Association (FHWA) bridge database are listed as structurally deficient. This has created a need to either replace or strengthen bridges quickly and efficiently. Due to high costs for total replacement of deficient bridges, strengthening of existing bridges is a more economical alternative. A technique that has been developing over the past two decades is the strengthening of bridges using carbon fiber reinforced polymer (CFRP) sheets. The CFRP sheets are attached to the bottom of the bridge girders using structural adhesives so that the CFRP becomes an integral part of …

Application Of Non-Destructive Testing In Evaluating Reinforced Concrete Structural Elements In Buildings, I Rubaratuka

Tanzania Journal of Engineering and Technology (TJET)

Of recent a large number of existing reinforced concrete buildings have required reconstruction, renovation and improvement. This tendency poses a number of problems that have to be solved, the main one being to determine the actual strength condition of the structural components/elements of the building. It includes determination of the quality of materials used, specification of the types and description of apparent faults and damages and extent of wear of the building. To undertake this evaluation, non – destructive testing methods are used. In this paper, applications of non – destructive testing methods to determine the strength state of reinforced …

Implementation Of A Non-Metallic Reinforced Bridge Deck, Volume 2: Thayer Road Bridge, Robert J. Frosch, Ali Cihan Pay

JTRP Technical Reports

The primary maintenance problem with bridges in Indiana has been deterioration of the concrete deck which is often related to corrosion of the reinforcing steel. While a corrosion protection system consisting of epoxy-coated reinforcement in combination with 2-1/2 in. of Class C concrete cover has been used in Indiana, research and experience have demonstrated that this system can be compromised. As an alternative solution to the corrosion problem in reinforced concrete, fiber reinforced polymer (FRP) bars which are corrosion resistant can be provided as reinforcement. This research was divided into two phases directed towards the implementation of a nonmetallic reinforced …

Interaction Between Micro-Cracking, Cracking, And Reduced Durability Of Concrete: Developing Methods For Considering Cumulative Damage In Life-Cycle Modeling, Zhifu Yang, W. Jason Weiss, J. Olek

JTRP Technical Reports

It is becoming increasingly popular to utilize numerical simulation models to predict the long-term performance of concrete pavements and structures. The majority of these models have been developed using laboratory test data that considers concrete in an uncracked state. While uncracked concrete exists as the best case scenario, frequent cracking occurs in real structures that could have a profound impact on life cycle performance. Cracks from several sources may accumulate and interact thereby accelerating the deterioration of concrete. For example, the distributed cracking caused by freeze/thaw damage can substantially increases the rate of water absorption and reduces the load carrying …

An Investigation On Transversely Prestressed Concrete Bridge Decks, J. A. Ramirez, Jhon Paul Smith

JTRP Technical Reports

This study is concerned with the development of design specifications for the use of transverse post-tensioning in concrete bridge decks. The ultimate goal behind this proposal is to improve the durability of concrete bridge superstructures. Experimental results from previous studies are used to validate the analytical models implemented in the development of the design specifications. It is found that the required distribution of transverse post-tensioning is such that different application levels of prestressing are required in regions containing the interior and exterior (or outermost) diaphragms. It is also concluded that the magnitude of such transverse forces is a function of …

Design Of Durable Concrete Railroad Crossings, Anthony J. Lamanna, Charles F. Scholer

JTRP Technical Reports

Existing precast concrete railroad crossings in the state of Indiana are experiencing too short a life expectancy. This study proposes methods that can be used to produce durable concrete railroad crossings with satisfactory rideability, durability, and longevity. Thirty-two precast concrete railroad crossings were visited in central and northern Indiana. Failures were determined to belong to three major categories: structural capacity causes, environmental causes, and material property causes. A concrete mix was evaluated at three different polyolefin fiber contents and without fibers. Beams were tested in flexure, and modulus of rupture and first crack deflection were recorded for each beam. Cylinders …

Performance-Related Specifications For Concrete Bridge Superstructures, Volume 4: Bond Of Epoxy-Coated Bars With Thicker Coatings, J. A. Ramirez, Michael K. Appelhans

JTRP Technical Reports

In Volume 4 of the final report, the results of an evaluation of the bond performance of epoxy-coated bars with a coating thickness up to 18 mils are presented. The experimental work on the bond performance of epoxy-coated bars with thickness up to 18 mils indicates that the current AASHTO requirements for development length of epoxy-coated bars up to #8 could be safely extended to coating thickness of up to 18 mils. Thus, no change to the bond specifications is recommended in order to implement the use of bars with diameters up to a #8 with epoxy-coating thickness up to …

Performance-Related Specifications For Concrete Bridge Superstructures, Volume 3: Nonmetallic Reinforcement, Robert J. Frosch, Christopher P. Mosley, Ahmet Koray Tureyen

JTRP Technical Reports

In Volume 3 of the final report, research work conducted to investigate the behavior of fiber reinforced polymer (FRP) reinforcement is summarized. This study focused on the behavior of FRP reinforced concrete structures with an emphasis on bond and shear. For the bond investigation, three series of beam splice tests were performed on specimens reinforced with steel, glass FRP, and aramid FRP to determine the effect of the different types of reinforcement on bond, cracking, and deflections. The test results indicate that the use of FRP reinforcement leads to lower bond strengths and, therefore, require longer development lengths. The specimen …