Engineering Commons^™

Quality Assurance And Quality Control For Reinforced Concrete Inspections, Calvin O. Walters Jr.

Publications and Research

Ensuring the safety and longevity of structures is paramount in concrete construction projects. Cases like the Big Dig ceiling collapse, which occurred on July 10, 2006, when a concrete ceiling panel measuring 20' x 40' and debris weighing 26 short tons (52,000 lb) fell within Boston's Fort Point Channel Tunnel, underscore this importance (Wald, M. L., 2007). Quality Assurance (QA) and Quality Control (QC) are crucial in mitigating such risks. QA ensures that materials and methods meet predetermined performance, design, and reliability standards specified in contracts and customer arrangements. On the other hand, QC is a strategic process businesses use …

Review Of Fly-Ash As A Supplementary Cementitious Material, Nikki Shaji, Niall Holmes Dr., Mark Tyrer

Conference papers

This paper presents a review of fly-ash as a Supplementary Cementitious Material (SCM) in concrete in terms of its effects on hydration and durability. The climate change agenda has focused the cement and concrete industry on using low embodied CO2 materials and much effort has been made on incorporating industrial by-products into cement as SCMs. With worldwide cement production (circa 4 billion tonnes) currently accounting for approximately 8% of global CO2 emissions and 7% of industry energy use, the use of suitable SCMs to partially replace cement in concrete is extremely important. However, while coal-fired power stations are in the …

Application Of Biochar As Beneficial Additive In Concrete, Temirlan Barissov

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

Biochar is a high-carbon solid material produced via thermal decomposition of organic biomass in a low-oxygen environment. Characterized with high water retention properties and high alkalinity, biochar is generally used for soil amendment and fertilization purposes. This study is intended to explore the feasibility of using biochar as a beneficial additive of the most used manmade material, concrete. Literature review revealed several studies where biochar was successfully implemented as an additive in concrete. The beneficial influence of biochar on the mechanical characteristics of concrete is based on nucleation and densification effects. However, the internal microstructure, porosity and chemical composition of …

Reliability Of Sfrp-Strengthened Rc Bridge Columns Subjected To Blast Loads, Ahmad Alsendi, Christopher D. Eamon

Civil and Environmental Engineering Faculty Research Publications

The reliability of reinforced concrete bridge columns strengthened with externally bonded, steel-fiber reinforced polymer fabric subjected to blast loads was investigated. Columns were modeled with a nonlinear finite element approach that considers material damage, fracture, and separation. Different concrete strengths, longitudinal reinforcement ratios, and gravity and blast load levels were considered, while uncertainties in material strength and stiffness parameters, as well as load characteristics, were incorporated in the probabilistic analysis. It was found that the use of SFRP can allow significant increases in blast load while maintaining the same level of column reliability.

Quantitative Assessment Of Alkali-Silica Reaction In Small And Large-Scale Concrete Specimens Utilizing Nonlinear Acoustic Techniques, Clayton Malone

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

Nonlinear resonance techniques have been shown to be sensitive to microcracking in materials, including alkali-silica reaction (ASR) damage in concrete. However, application of nonlinear resonance tests have been limited due to the difficulty of application to large-scale field structures and the inability to quantitatively relate material nonlinearity with damage development. In this study, the development of ASR in concrete prisms and large concrete beam specimens of varying aggregate types and specimen sizes was monitored using linear and nonlinear resonance techniques.

For the concrete prisms, although the linear resonance frequency test could detect initiation and development of ASR damage in specimens …

Quantitative Resistance Assessment Of Sfrp-Strengthened Rc Bridge Columns Subjected To Blast Loads, Ahmad Alsendi, Christopher D. Eamon

Civil and Environmental Engineering Faculty Research Publications

The blast resistance of a typical reinforced concrete bridge pier column design was modeled with a nonlinear finite element approach that considers material damage, fracture, and separation. While varying concrete strength, amount of longitudinal reinforcing steel, and gravity load, the effect of applying an externally bonded steel fiber reinforced polymer (SFRP) wrapping was assessed. The presented approach uniquely quantifies column blast resistance in terms of charge weight. It was found that blast capacity was roughly linearly related to concrete strength and steel reinforcement ratio, the former of which is most influential. It was further found that a single layer of …

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 …

Evaluation Of Internally Cured Bridge Deck Concrete With Standard And Optimized Aggregate Gradation, Arman Abdigaliyev

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

Due to the relatively high cement content and low water-to-cement ratio (w/c) used, bridge deck concrete is prone to premature cracking. Internal curing has been found to greatly reduce the chance of premature cracking as well as concrete deterioration. This research developed internally cured bridge deck concrete based on a local mix design in Nebraska. Four different lightweight fine aggregate (LWFA) as internal curing agents were evaluated and their effects on fresh, mechanical, durability, and shrinkage properties of concrete were studied. The study focused on resolving two issues associated with fine aggregate replacement based on Bentz equation. To identify the …

Uhpc Shear Keys In Concrete Bridge Superstructures, Craig Newtson, Brad Weldon, Elsy Flores, Jordan Varbel, William Toledo

Publications

This research investigated the use of locally produced ultra-high performance concrete (UHPC) as a grouting material to repair deteriorated shear keys. Shear keys are used in adjacent girder superstructures to produce monolithic behavior and load transfer across the structure. Shear key durability is a concern since shear key degradation can jeopardize the integrity of the structure. Transportation agencies have reported that 75% of distress in adjacent girder bridges is due to cracking and de-bonding along shear keys. Previous research has shown that locally produced UHPC has excellent mechanical and durability properties. UHPC has also been shown to have good bonding …

Use Of Bagasse Ash As A Concrete Additive For Road Pavement Application, Gabriel Arce, Marwa Hassan, Maria Gutierrez, Michele Barbato

Publications

The objective of this study was to evaluate the use of sugarcane bagasse ash (SCBA) as a partial replacement of cement in concrete for road pavement application. The study explored the pozzolanic activity of SCBA produced from three different processing methodologies (i.e., raw SCBA, controlled SCBA and post-processed SCBA). The experimental results revealed that SCBA produced by the controlled burning of sugarcane bagasse fiber (SBF) at 650°C and grinding (C-650), presented the maximum pozzolanic activity. However, this SCBA production process was deemed challenging for large-scale industrial application due to low SCBA yield (i.e., 3 to 6%). On the other hand, …

Retrofitting Of Bridge Elements Subjected To Predominantly Axial Load Using Uhpc Shell, Mahsa Farzad

FIU Electronic Theses and Dissertations

In the United States, ~30% of the ~600,000 highway bridges are categorized as structurally deficient or functionally obsolete. These bridges should be replaced or upgraded to sustain the transportation needs of the growing public and private sectors of the U.S. economy. It is not uncommon for structures to have advanced levels of corrosion-induced damage where major repair and maintenance works are required. However, the transportation infrastructure may undergo disruption during rehabilitation causing interruption to critical economic public, civil and commercial activities. This mandates the development of new techniques and materials for accelerated rehabilitation and resilience. To address this issue, a …

Epoxy Interlocking: A Novel Approach To Enhance Frp-To-Concrete Bond Behavior, Cheng Jiang, Baolin Wan, Yu-Fei Wu, John Omboko

Civil and Environmental Engineering Faculty Research and Publications

This paper presents a novel approach which can enhance the interfacial bond behavior between fiber reinforced polymer (FRP) composite material and concrete. Epoxy ribs are formed by grooving on the concrete surface before epoxy is applied. The dowel action from the epoxy ribs leads to an “epoxy interlocking” effect. The mechanism of the proposed epoxy interlocking approach was analyzed in this paper from both adhesion and interlocking aspects. Furthermore, the partial interaction of the epoxy interlocking was quantified and calibrated by experimental results. The epoxy interlocking in the tested specimens led to an 88.8% increase in bond strength on average. …

Self-Healing Microcapsules As Concrete Aggregates For Corrosion Inhibition In Reinforced Concrete, Homero Castaneda, Marwa Hassan, Miladin Radovic, Jose Milla

Publications

Reinforced Concrete (RC) structures are vital to the US’s civil infrastructure for their strength and versatility. Unfortunately, RC elements deteriorate rapidly when exposed to corrosive environments. One possible solution is to extend the life of RC elements and systems using microencapsulated corrosion inhibitors to reduce the rebar corrosion rate. The capsules house an anodic corrosion inhibitor agent including calcium nitrate (CN) and triethanolamine (TEA). The integration of such microencapsulated materials will enhance the durability and extend the useful life by controlling the corrosion precursors and the corrosion process during damage evolution. Therefore, this work aims to develop and characterize the …

Bridge Deck Overlays Using Ultra-High Performance Concrete, Craig Newtson, Brad Weldon

Publications

This study investigated the use of a locally produced ultra-high performance concrete (UHPC) as an alternative to typical overlay materials. Several bond strength tests including slant-shear, splitting tension, and direct tension tests were performed to assess the bond strength between UHPC and normal strength concrete (NSC) substrate with varying surface textures. Tests were also conducted to assess the early-age and longer-term shrinkage behavior and coefficient of thermal expansion of the UHPC as well as rapid chloride permeability testing. Good bond between UHPC and NSC substrate was observed even with inadequate surface texture. Combined shrinkage and thermal effects were investigated for …

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 …

Enhancing Frp-To-Concrete Bond Behavior By Epoxy Ribs, Cheng Jiang, Baolin Wan, John Omboko

Civil and Environmental Engineering Faculty Research and Publications

The bond between external bonding (EB) of fiber reinforced polymer (FRP) composite materials to concrete is the weakest link in the strengthened concrete flexural members. There are three mechanisms to transfer the interfacial shear between FRP and the concrete substrate, i.e., adhesion, interlocking and friction. This paper proposes a new approach by grooving on the concrete surface before applying epoxy to make epoxy ribs to increase interlocking. An experimental program was conducted to verify the effectiveness of the proposed epoxy ribs. Six grooves perpendicular to the fiber direction were cut on the bonding surface of the concrete blocks. The grooves …

A Novel Concrete-Based Sensor For Detection Of Ice And Water On Roads And Bridges, Habib Tabatabai, Mohammed Aljuboori

Civil and Environmental Engineering Faculty Articles

Hundreds of people are killed or injured annually in the United States in accidents related to ice formation on roadways and bridge decks. In this paper, a novel embedded sensor system is proposed for the detection of black ice as well as wet, dry and frozen pavement conditions on roads, runways, and bridges. The proposed sensor works by detecting changes in electrical resistance between two sets of stainless steel poles embedded in the concrete sensor to assess surface and near-surface conditions. A preliminary decision algorithm is developed that utilizes sensor outputs indicating resistance changes and surface temperature. The sensor consists …

Fluid Isolator, Purdue Ect Team

ECT Fact Sheets

The reliability of concrete infrastructure is vital to ensuring daily life, as well as commerce, can progress without interruption. From the pavement of interstate highways to the driveways and sidewalks in a local neighborhood, concrete is expensive to install and often even more expensive, and intrusive, when it needs to be replaced. Unfortunately, to maintain functionality in winter climates concrete is heavily exposed to deicing salts. This not only affects the roads, driveways, and sidewalks where salt is applied directly, but many other areas such as parking and residential garages where vehicles (and people) will track salt along with water …

The Confinement Effects On The Fiber Pullout Response Of Ultra-High Performance Concrete (Uhpc, Arden Mcswain

Honors College

Fiber pullout tests were conducted on more than ninety 10 mm by 10 mm cylindrical concrete specimens with a single, straight steel fiber embedded 10 mm in the center of the concrete specimen. Each specimen was subjected to one of three levels (90 N, 2000 N, 4000 N) of confining force applied by a steel fixture and a servo-hydraulic Instron test frame was used to conduct fiber pullout tests. A previously published fiber pullout model was used to determine the approximate bond strength and frictional stress experienced by the fiber-concrete matrix for each of the three confinement levels. Results show …

Development Of A Lightweight Hurricane-Resistant Roof System, Ehssan Amir Sayyafi

FIU Electronic Theses and Dissertations

Roofs are the most vulnerable part of the building envelope that often get damaged when subjected to hurricane winds. Damage to the roofs has a devastating impact on the entire structure, including interior losses and service interruptions. This study aimed at the development of a novel light-weight composite flat roof system for industrial, commercial and multi-story residential buildings to withstand Category 5 hurricane wind effects based on the Florida Building Code requirements for hurricane-prone regions, the strictest wind design code in the United States.

The proposed roof system is designed as a combination of two advanced materials: ultra-high performance concrete …

Evaluating A New Cem Iii/A Cement For Concretes Exposed To Harsh Acid Rich Environments, David Thompson, Niall Holmes, John Reddy

Conference papers

The Irish Annex to the European specification, performance, production and conformity of concrete, IS EN 206, recommends CEM III/B cement for acid rich environments containing between 66 to 80% GGBS. However, BS 8500, the UK annex to EN 206 and the British Research Establishment (BRE) Special Digest 1, recommends CEM III/A cement with a GGBS range of 36-65%. This project investigated the performance of a new CEM III/A cement produced by Ecocem Ireland in concretes exposed to such environments using an extensive suite of laboratory tests.

In Ireland, up to €5.8bn will be invested to provide fresh drinking water and …

Innovative Modular High Performance Lightweight Decks For Accelerated Bridge Construction, Sahar Ghasemi

FIU Electronic Theses and Dissertations

At an average age of 42 years, 10% of the nation’s over 607,000 bridges are posted for load restrictions, with an additional 15% considered structurally deficient or functionally obsolete. While there are major concerns with decks in 75% of structurally deficient bridges, often weight and geometry of the deck further limit the load rating and functionality of the bridge. Traditional deck systems and construction methods usually lead to prolonged periods of traffic delays, limiting options for transportation agencies to replace or widen a bridge, especially in urban areas.

The purpose of this study was to develop a new generation of …

The Performance And Service Life Prediction Of High Performance Concrete In Sulfate And Acidic Environments, Shuo Zhang

FIU Electronic Theses and Dissertations

Concrete substructures are often subjected to environmental deterioration, such as sulfate and acid attack, which leads to severe damage and causes structure degradation or even failure. In order to improve the durability of concrete, the High Performance Concrete (HPC) has become widely used by partially replacing cement with pozzolanic materials. However, HPC degradation mechanisms in sulfate and acidic environments are not completely understood. It is therefore important to evaluate the performance of the HPC in such conditions and predict concrete service life by establishing degradation models.

This study began with a review of available environmental data in the State of …

Post-Tensioned Concrete Shear Wall, Purdue Ect Team

ECT Fact Sheets

The post-tension concrete shear wall by Tipping Mar will replace the conventional concrete shear wall in earthquake prone areas in many instances, depending on the height and scale of the building.

Numerical Simulation Of Prestressed Precast Concrete Bridge Deck Panels Using Damage Plasticity Model, Wei Ren, Lesley Sneed, Yang Yang, Ruili He

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

No abstract provided.

The Role Of Shrinkage Strains Causing Early-Age Cracking In Cast-In-Place Concrete Bridge Decks, Tayyebeh Mohammadi, Baolin Wan, Christopher M. Foley

Civil and Environmental Engineering Faculty Research and Publications

Early-age cracking in cast-in-place reinforced concrete bridge decks is occurring more frequently now than three decades ago and principle factors that lead to early-age deck cracking are not fully understood. A finite element (FE) simulation methodology for assessing the role of shrinkage-induced strains in generating early-age bridge deck cracking is described. The simulations conducted indicate that drying shrinkage appears to be capable of causing transverse (and possibly longitudinal) bridge deck cracks as early as 9 to II days after bridge deck placement. The drying-shrinkage induced stresses would result in transverse cracking over interior pier supports in a typical bridge superstructure …

Performance Of Frp-Retrofitted Concrete Bridge Columns Under Blast Loading, R. Zheng, P. Zohrevand, H. Erdogan, Amir Mirmiran

Civil Engineering Faculty Publications and Presentations

Contrary to military or essential government buildings, most bridges are designed without any consideration for blast resistance. Fiber-reinforced polymers (FRPs) can provide an effective means for strengthening of critical bridges against such loading. This study has focused on the effectiveness of FRP retrofitting in the dynamic response of reinforced concrete bridge columns under blast loading. Using a simplified equivalent I-section with a virtual material lumped at the two flanges; a lightly meshed uniaxial finite element model was developed and successfully validated against previous studies. The proposed model was then used for a thorough parametric study on the blast resistance of …

A Critical Review Of Research On Reuse Of Mechanically Recycled Frp Production And End-Of-Life Waste For Construction, Ardavan Yazdanbakhsh, Lawrence C. Bank

Publications and Research

For the last three decades, fiber reinforced polymer (FRP) composite materials have been widely used in major engineering industries. Managing FRP waste is becoming an important issue due to the growth in the production of FRP composite materials. In this article, the issue of FRP waste management is discussed and the commonly used methods for the handling of FRP waste are reviewed. One potentially viable use of FRP waste is in the partial replacement of fillers or aggregates in cementitious materials (particularly portland cement mortar and concrete). A number of important prior investigations performed on the use of FRP waste …

Electrochemical-Mechanistic Model For Concrete Cover Cracking Due To Corrosion Initiated By Chloride Diffusion, Goli Nossoni, Ronald S. Harichandran

Civil Engineering Faculty Publications

A holistic electrochemical-mechanistic model of the corrosion of steel reinforcing bars inside concrete that accounts for the diffusion of oxygen and moisture into the concrete and rust layers, the densification of rust due to confinement, the flow of rust into the concrete pores, the development of internal pressure due to rust buildup, and cracking of the concrete cover is presented. The relationship between the corrosion current and the pressure buildup due to the corrosion products for different concrete cover thicknesses and concrete quality was calibrated through experiments using an accelerated corrosion test with an applied current. Results from finite-element analysis …

Study On Surface Permeability Of Concrete Under Immersion, Jun Liu, Feng Xing, Biqin Dong, Hongyan Ma, Dong Pan

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

In this paper, concrete specimens are immersed in ultrapure water, to study the evolutions of surface permeability, pore structure and paste microstructure following the prolonging of immersion period. According to the results, after 30-day immersion, the surface permeability of concrete becomes higher as compared with the value before immersion. However, further immersion makes the surface permeability decrease, so that the value measured after 150-day immersion is only half that measured after 30-day immersion. The early increase in surface permeability should be mainly attributed to the leaching of calcium hydroxide, while the later decrease to the refinement of pore structure due …