Civil Engineering Commons^™

Continuous Moisture Measurement During Pavement Foundation Construction: Laboratory Measurements, Isaac Esteban Zuniga

Open Access Theses & Dissertations

Moisture content directly affects all properties of subgrade materials. A rapid, continuous, and accurate technique to determine moisture content during subgrade construction is the next step needed to improve the mechanistic-based quality of pavement foundations. In this study, six geomaterials were compacted to standard/modified proctor specifications and subjected to laboratory measurements to study the variations in their electromagnetic and electric properties with moisture content. The relationships between the seismic modulus, unconfined compressive strength, lightweight deflectometer, and moisture content for the same geomaterials were also established. Large-scale replicate specimens were also compacted and subjected to numerous measurements. The dielectric constant measured …

The Effects Of Curing Temperature On The Hydration Kinetics Of Plain And Fly Ash Pastes And Compressive Strength Of Corresponding Mortars With And Without Nano-Tio2 Addition., Dan Huang, Mirian Velay-Lizancos, Jan Olek

International Conference on Durability of Concrete Structures

Incorporation of fly ash in cementitious systems containing ordinary portland cement (OPC) increases their long-term strength and durability. However, replacement of cement by fly ash also reduces the heat of hydration of such systems and reduces early-age strength development. The reduced rate of strength development can increase the risk of durability problems, e.g. scaling, in cases when young concrete is exposed to low temperatures and deicing chemicals. This study investigated the potential of nano-titanium dioxide (nano-TiO₂) particles to modify the hydration kinetics of fly ash pastes and compressive strength development of corresponding mortars cured under low (4°C) and …

Structural Performance Evaluation Of Dynamic Message Signs With Adhesive And Welded Joints, Ibin Amatya

Electronic Theses and Dissertations

The ultimate objective of this study was to determine the structural performance of the Dynamic Message Sign (DMS) bonded with chemical adhesive in terms of ultimate strength and fatigue strength. To achieve this objective, this study first investigated the effects of various parameters, including humidity and temperature on tensile, shear, peel, and cleavage strength through small-scale tests of adhesive specimens with variation in specimen width. The tensile, shear, peel, and cleavage specimens were conditioned in a temperature-humidity controlled chamber prior to its testing. The tensile, shear, peel, and cleavage specimens with different widths were tested according to American Society for …

Effect Of Recycled Concrete Aggregates On The Long-Term, Elastic, Total Deflection And Strength Of Precast Prestressed Hollow Core Concrete Slabs, Lizeth Marisol Gomez Santana

Civil Engineering Theses

Concrete constitutes the largest portion of construction and demolition waste generated each year in the United States. The Environmental Protection Agency (EPA) estimates that the total production of construction and demolition of concrete waste during 2015 was 381.8 million tons. In order to reduce the economic and environmental effects of waste concrete, researchers have begun to incorporate it into concrete mixtures. However, the inherent variability in mechanical properties between RCA sources makes it difficult to quantify the maximum permissible replacement of natural aggregate and the end-result properties of concrete. This project investigates the use of recycled concrete aggregates (RCA) obtained …

Thin-Walled Steel Tubular Circular Columns With Uniform And Graded Thickness Under Bidirectional Cyclic Loading, Qusay Al-Kaseasbeh, Iraj H.P. Mamaghani

Civil Engineering Faculty Publications

Thin-walled steel tubular circular columns are becoming an increasingly attractive choice as cantilever bridge piers due to their architectural, structural and constructional advantages. This paper aims to evaluate the strength and ductility of thin-walled steel tubular circular columns with uniform thickness (BC) and graded thickness (BGC) under bidirectional cyclic lateral loading in the presence of constant axial force. The analysis is carried out using a finite-element model (FEM) which is substantiated based on the experimental results in the literature. Then, the proposed BGC column with size and volume of material equivalent to the BC column is investigated. As a part …

Development Of A Mix Design Adjustment Method For Fiber Reinforced Concrete And Super High Performance Concrete Based On Excess Paste, Joe Malloy

Department of Civil and Environmental Engineering: Dissertations, Theses, and Student Research

The main objective of this study was to develop a mix design adjustment method for Fiber Reinforced Concrete (FRC) that would maintain appropriate workability while improving hardened concrete performance. A literature review was conducted to examine existing methods for adjusting mix designs to account for fiber introduction. It was found that while increasing fine aggregate and cement paste content can make up for lost workability with the addition of fibers, no rational mix design adjustment method is available. Reference mix designs from the Nevada Department of Transportation and the Nebraska Department of Transportation were used, and this study focused on …

Development Of Environmentally-Friendly Stabilization Methods For Transportation Infrastructure Based On Geopolymers, Miladin Radovic, Anand Puppala

Data

Corresponding data set for Tran-SET Project No. 17GTTAM02. Abstract of the final report is stated below for reference:

"Geopolymers (GPs) have received much attention as an eco-friendly and sustainable alternative to conventional chemical additives, since they can be processed at room temperatures from aqueous solutions by utilizing waste materials (e.g. fly ash) or abundant natural sources (e.g. clay). A collaborative research study is carried out by teams from Texas A&M University (TAMU) and University of Texas at Arlington (UTA) to investigate the effectiveness of GPs for stabilizing base and subgrade materials by considering the strength and shrink-swell characteristics. Two types …

Development Of Environmentally-Friendly Stabilization Methods For Transportation Infrastructure Based On Geopolymers, Miladin Radovic, Anand Puppala

Publications

Geopolymers (GPs) have received much attention as an eco-friendly and sustainable alternative to conventional chemical additives, since they can be processed at room temperatures from aqueous solutions by utilizing waste materials (e.g. fly ash) or abundant natural sources (e.g. clay). A collaborative research study is carried out by teams from Texas A&M University (TAMU) and University of Texas at Arlington (UTA) to investigate the effectiveness of GPs for stabilizing base and subgrade materials by considering the strength and shrink-swell characteristics. Two types of clay, obtained from the North Dallas area, were mixed with a potassium-based GP synthesized from metakaolin and …

Coir Fiber Reinforced Concrete, Jose De La Serna, Moses Karakouzian

AANAPISI Poster Presentations

This poster exhibits the testing and research done on general Portland Cement Concrete with the addition of coir (coconut) fibers as reinforcement. Using the fundamental constituents of cement (water, cement, fine and coarse aggregate) and processed coir fiber, concrete specimens were batched to test for compressive and flexural strengths (per appropriate ASTM standards). Cylindrical and rectangular beam specimens were subjected to loadings until failure occurred. The capacity and modes of failures of the specimens were observed. It was determined that:

• The addition of processed coir fibers decreases the overall strength of general Portland Cement Concrete. • The tested concrete’s …

Dynamic Mechanical Properties And Microstructure Of Graphene Oxide Nanosheets Reinforced Cement Composites, Wujian Long, Jingjie Wei, Hongyan Ma, Feng Xing

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

This paper presents an experimental investigation on the effect of uniformly dispersed graphene oxide (GO) nanosheets on dynamic mechanical properties of cement based composites prepared with recycled fine aggregate (RFA). Three different amounts of GO, 0.05%, 0.10%, and 0.20% in mass of cement, were used in the experiments. The visual inspections of GO nanosheets were also carried out after ultrasonication by transmission electron microscope (TEM) atomic force microscope (AFM), and Raman to characterize the dispersion effect of graphite oxide. Dynamic mechanical analyzer test showed that the maximum increased amount of loss factor and storage modulus, energy absorption was 125%, 53%, …

Feasibility Study Of Using Recyclable Polyethylene (Pet) Materials As Coarse Aggregate For Concrete Mixtures, Philip M. Angelo

Construction Management

The feasibility of using recyclable household plastics, specifically those made of polyethylene, commonly used in water and soda bottles, as a replacement for concrete coarse aggregate, was assessed. A method was developed for cutting polyethylene materials into fibrous strips. These strips were then used as a replacement for the rock coarse aggregate in batches of concrete. Standard 6” x 12” test cylinders were made using the concrete mixture and subject to destructive compressive testing in order to yield the compressive strength of the concrete mix 7, 14, 21, and 28 days after pouring. Three mixtures were tested, one control with …

Strength Of Reinforced Concrete Beams With High-Strength Steel, Brian C. Rogers, Aishwarya Puranam, Santiago Pujol

The Summer Undergraduate Research Fellowship (SURF) Symposium

Structures are commonly made of reinforced concrete, which is a composite material made of concrete and steel reinforcement. Using high-strength steel, with yield stress larger than 100 ksi, could help reduce the quantity of steel required in structural members, thus reducing costs and improving constructability. The hypothesis being tested is that smaller quantities of high-strength steel reinforcement (HSSR) can be used in place of conventional steel in reinforced concrete beams while maintaining similar strength and deformation at failure. Two reinforced concrete beams with two different types of longitudinal steel reinforcement were constructed. The beams were 18 in. wide, 30 in. …

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 …

The Effect Of Mechano-Chemical Activation Of Fly Ash- Nanoparticle Blends On Performance Of Cement Based Composites And Self-Consolidating Concrete, Rani G K Pradoto

Theses and Dissertations

Other than water, portland cement concrete is the most used commodity. Major parts of civil and transportation infrastructure, including bridges, roadway pavements, dams, and buildings are made of concrete. Because of wide-scale applications of these important structures in different climatic zones and associated exposures, concrete durability is often of major concern. In 2013, the study of American Society of Civil Engineers (ASCE) estimated that one-third of America’s major roads are in poor or mediocre condition [1]. The same article reports that annual investments of $170 billion on roads and $20.5 billion for bridges are needed to substantially improve the condition …

Experimental And Predicted Behavior Of Frp Beam-Columns Including Retrofitting, Ali Al-Huazy

Civil & Environmental Engineering Theses & Dissertations

This thesis presents the outcome of a theoretical and experimental study of Fiber Reinforce Polymer (FRP) beam-columns with uniaxial bending and including retrofitting. The research involved the design and fabrication of a testing apparatus which was then used for a series of beam-column tests. Three different types of beam-column cross sections were used, namely, channel section, I-section, and square tube section. Six non-retrofitted beam-columns were tested in addition to two retrofitted ones. The members were subjected to an eccentric vertical load applied through a lever arm generating gradually increasing axial load and uniaxial bending moment up to the maximum load. …

Effect Of Void Geometry On Strength, Stiffness, And Failure Modes Of Rock-Like Materials, Omed Yousif

UNLV Theses, Dissertations, Professional Papers, and Capstones

The host rock of portion of the first proposed high-level nuclear waste repository in the United States of America (Yucca Mountain, Nevada) is tuff rock that contains voids (lithophysae) with different shapes, sizes, and distributions. The existence of these voids can cause a dramatic change in the rock's mechanical properties such as uniaxial compressive strength, UCS, and Young's modulus, E. Accordingly, in an experimental program, the effects of void existence on the engineering properties of the tuff rocks was explored in a work of US Department of Energy conducted in the Department of Civil and Environmental Engineering and Construction of …

Stabilization Of Iron Mine Tailings Through Microbially Induced Calcite Precipitation, Noah D. Buikema

Dissertations, Master's Theses and Master's Reports - Open

Mine tailings are deposited into large-scale impoundments. Seasonal temperature fluctuations destabilize particles on the impoundment surface. Wind-induced shear stresses on the destabilized particles can in turn result in suspension of micron-sized particles into the atmosphere, creating dust storms that pose hazards to humans and the environment. Thus, efficient and sustainable methods of dust abatement are needed. One novel method for controlling dust emissions is biomodification. For example, Sporosarcina pasteurii can promote biocalcification in soil via ureolysis. However, application of this method to fined grained materials, such as mine tailings, is challenging. The goal of this work was to perform a …

Mechanical Behavior Of Grouted Sands, Ryan C. Ortiz

Theses and Dissertations--Civil Engineering

Grouting techniques have been in used for many years, but several new grout materials have surfaced in recent decades that have re-defined the boundaries of the limitations of grouting programs. Typically these applications are used for seepage control in earthen impoundments, but strength of these earthen impoundments should be considered where there is potential for movement in the grouted soil mass. This study investigated initial conditions that could affect grout application effectiveness. The initial conditions in question were soil grain size and in situ moisture content. Two grouts were used, ultrafine and acrylate, and variations in pure grout properties were …

Mechanical Characteristics Of Organically Modified Fly Ash-Kaolinite Mixtures, Xin Kang

Doctoral Dissertations

"Fly ash is a hazardous waste material to the environment. Beneficial reuse of fly ash, however, brings economic and environmental benefits, i.e., decreases the cost of disposal, reduces greenhouse gas emission, and improves mechanical properties of construction materials. Due to the lack of pozzolanic properties, the reuse rate of Class F fly ash in geotechnical engineering is relatively low (ACAA 2013). In order to promote the effectiveness and sustainability of high volume reuse of class F fly ash in geotechnical engineering, biopolymers (Chitosan, and Xanthan gum) and synthetic polymers (Polyethylene Oxide, PEO) were used instead of the traditional stabilizers to …

Geomechanical Characterization Of Marcellus Shale, Rafael Villamor Lora

Graduate College Dissertations and Theses

Given their potential applications for a number of engineering purposes, the geomechanics of shale reservoirs is becoming one of the most important issues in modern geomechanics. Borehole stability modeling, geophysics, shale oil and shale gas reservoirs, and underground storage of CO2 and nuclear waste are some of these potential applications to name a few. The growing interest in these reservoirs, as a source for hydrocarbons production, has resulted in an increasing demand for fundamental material property data.

Laboratory analysis and constitutive models have shown that rock elastic and deformational properties are not single-value, well-defined parameters for a given rock. Finding …

Effects Of Using Silica Fume And Polycarboxylate-Type Superplasticizer On Physical Properties Of Cementitious Grout Mixtures For Semiflexible Pavement Surfacing, Hilmi Mahmud

Hilmi Mahmud

Semi-flexible pavement surfacing is a composite pavement that utilizes the porous pavement structure of the flexible bituminous pavement, which is subsequently grouted with appropriate cementitious materials. This study aims to investigate the compressive strength, flexural strength, and workability performance of cementitious grout. The grout mixtures are designed to achieve high strength and maintain flow properties in order to allow the cement slurries to infiltrate easily through unfilled compacted skeletons. A paired-sample t-test was carried out to find out whether water/cement ratio, SP percentages, and use of silica fume influence the cementitious grout performance. The findings showed that the replacement of …

Compression Testing And Failure Modes Of Steel-Concrete Composite (Sc) Structures For Nuclear Containment, Patrick Michael Wanamaker, Amit H. Varma

The Summer Undergraduate Research Fellowship (SURF) Symposium

Although being able to provide much cleaner power than burning coal and other fossil fuels, nuclear power plants are still a tough sell to the general public due to their history of being spontaneously dangerous. The containment structures surrounding these nuclear plants, however, can play a huge role in reducing the risks associated with them. Relatively new designs for these containment assemblies, known as SC (steel-concrete composite) structures, aim to increase the strength and durability of the containment facilities while keeping costs down. By varying the spacing between shear studs, the ratio of concrete to steel, and the ratio of …

Effect Of Cement Chemistry And Properties On Activation Energy, Andre J. Bien-Aime

USF Tampa Graduate Theses and Dissertations

The objective of this work is to examine the effect of cement chemistry and physical properties on activation energy. Research efforts indicated that time dependent concrete properties such as strength, heat evolution, and thermal cracking are predictable through the concept of activation energy. Equivalent age concept, which uses the activation energy is key to such predictions. Furthermore, research has shown that Portland cement concrete properties are affected by particles size distribution, Blaine fineness, mineralogy and chemical composition. In this study, four Portland cements were used to evaluate different methods of activation energy determination based on strength and heat of hydration …

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 …

Stiffness Of Hot-Mix Asphalt, Terhi K. Pellinen, Shangzhi Xiao

JTRP Technical Reports

This research was initiated from a need to evaluate marginal mixtures that do not meet the Superpave mix design criteria for the air voids content requirements for the construction of hot mix asphalt pavements. The developed criteria is comprised of the base criteria derived from test data of as-placed field cores normalized to 7.5% air voids content, which provides the minimum stiffness and strength requirements for a mixture as a function of the traffic level. The stiffness of pavement cores is measured using Simple Shear Tester to obtain shear stiffness |G*| of mix and strength is measured using indirect tensile …

Stabilization And Improvement Of Organic Soils, Joonho Hwang, Aaron Humphrey, Antonio Bobet, Maria Caterina Santagata

JTRP Technical Reports

Peats and organic soils in general pose significant problems to geotechnical engineers due to their low strength, high compressibility and elevated creep. The research performed addressed one soil improving technique, deep soil mixing, that has been widely used for treating soft clays, but that especially in the US has found limited use in presence of organic soils. The work performed made use primarily of one soil sampled on Lindberg Road (LR) in West Lafayette, IN characterized by LOI= 45-52%, LL= 327%, PL= 162%, LLoven dried/LLnon-dried = 0.31, Gs = 2.05-2.12, fiber content ~2.29%, clay fraction = 40.6%. In addition, a …

Influence Of Curing Conditions On Strength Properties And Maturity Development Of Concrete, Scott Andrew Newbolds, Jan Olek

JTRP Technical Reports

In this study, the results of both laboratory studies and a field study, conducted to evaluate the effects of different curing conditions on the strength properties and maturity development of pavement concrete, are presented. Further, a laboratory study was performed to evaluate the maturity concept in relation to the degree of hydration of cement. Concrete specimens, beams and cylinders, were prepared in the field study. The specimens in the field were cured in one of four curing conditions: lime bath, sandpit, air, or by temperature match curing. Specimens were tested for flexural strength and compressive strength, respectively. The temperature of …

Performance Of Bridge Decks And Girders With Lightweight Aggregate Concrete, V. 2 Of 2, J. A. Ramirez, J. Olek, Eric Joseph Rolle, Brian Joseph Malone

JTRP Technical Reports

Structural lightweight concrete is a very versatile material and Haydite and Minergy lightweight aggregates can be utilized in the mixture development of concrete for use in girders and decks in bridges. More widespread use of lightweight aggregates (LWA) would result in savings in construction cost due to considerable dead load reduction.

The materials phase of this research study evaluated the fresh concrete properties (slump, unit weight, and air content), the mechanical properties of hardened concrete (compressive strength, tensile strength, flexural strength, static and dynamic modulus of elasticity, Poisson’s Ratio, and temperature development), and durability related parameters (air void distribution, freeze-that …

Performance Of Bridge Decks And Girders With Lightweight Aggregate Concrete, J. A. Ramirez, J. Olek, Eric Joseph Rolle, Brian J. Manlone

JTRP Technical Reports

Structural lightweight concrete is a very versatile material and Haydite and Minergy lightweight aggregates can be utilized in the mixture development of concrete for use in girders and decks in bridges. More widespread use of lightweight aggregates (LWA) would result in savings in construction cost due to considerable dead load reduction. The materials phase of this research study evaluated the fresh concrete properties (slump, unit weight, and air content), the mechanical properties of hardened concrete (compressive strength, tensile strength, flexural strength, static and dynamic modulus of elasticity, Poisson’s Ratio, and temperature development), and durability related parameters (air void distribution, freeze-thaw …

Stay-In-Place Deck Panels - Horizontal Shear Strength Of Bridge Deck Panels - Part 2, Phani Kumar Nukala, J. A. Ramirez, Robert H. Lee, Menashi D. Cohen

JTRP Technical Reports

One of the most economic methods of bridge deck construction consists of prestressed concrete deck panels used in stay-in-place forms in conjunction with the cast-in-place concrete topping instead of the traditional monolithic roadway deck slabs. The performance of this type of deck as a composite unit is only possible if the horizontal shear stress resulting from bending of the deck if effectively transferred across the interface of the two elements. It is assumed that horizontal shear stresses are transmitted across the interface due to bond between the precast panel and cast-in-place concrete acting in conjunction with the horizontal shear connectors …