Engineering Commons^™

Measurement And Monitoring Of Microwave Reflection And Transmission Properties Of Cement-Based Specimens, Sergey Kharkovsky, M. F. Akay, U. C. Hasar, C. D. Atis

Electrical and Computer Engineering Faculty Research & Creative Works

The results of measurement and monitoring of reflection and transmission properties of cement-based specimens (blocks of mortar, concrete) during long time of their service lives, including hydration process, and different curing conditions at microwave frequencies (X-band) are presented. A simple and inexpensive measurement system that utilizes the nondestructive and contactless free space method is used. Dependencies of the reflection and transmission coefficients on water-to-cement ratio, preparing and curing conditions of the specimens are demonstrated. It is shown that the reflection coefficient is approximately stable after hydration process while the transmission coefficient changes during long time of the specimen''s service life. …

Development And Evaluation Of Cement-Based Materials For Repair Of Corrosion-Damaged Reinforced Concrete Slabs, Rongtang Liu, J. Olek

JTRP Technical Reports

In this study, the results of an extensive laboratory investigation conducted to evaluate the properties of concrete mixes used as patching materials to repair reinforced concrete slabs damaged by corrosion are reported. Seven special concrete mixes containing various combinations of chemical or mineral admixtures were developed and used as a patching material to improve the durability of the repaired slabs. Physical and mechanical properties of these mixes, such as compressive strength, static modulus of elasticity, dynamic modulus of elasticity, and shrinkage were evaluated. Durability-related parameters investigated included resistance of concrete to penetration of chloride ions and freeze-thaw resistance. The results …

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 …

The Lineal Polarization Method For Corrosion Rate Measurement Of Reinforcing Bar Of Concrete In Situ, Ai-Ling Du, Wen-Tao Hou, He-Ming Zhang, Jian-Qun Luo

Journal of Electrochemistry

A linear polarization method was applied to measure corrosion rate of reinforcing bar of concrete in situ. Generally in the experiment, the area and shape of the reinforcing bar as a working electrode can be changed and adjusted according to our needs. But polarization area cannot be defined when reinforcing bar is polarized in situ, so that a real R p can't be obtained. Thus the purpose of present work is to improve the measurement system. We used the double_ring auxiliary electrodes made by ourselves. The size of the double_ring auxiliary electrodes was adjusted repeatedly until the real polarization area …

Influence Of Mortar Rheology On Aggregate Settlement, Michael F. Petrou, Baolin Wan, Francis Gadala-Maria, Venkata Giri Kolli, Kent A. Harries

Civil and Environmental Engineering Faculty Research and Publications

The influence of the rheology of fresh concrete on the settlement of aggregate is examined. Fresh concrete exhibits a yield stress that, under certain conditions, prevents the settlement of coarse aggregate, although its density is larger than that of the suspending mortar. Calculations, based on estimates of the yield stress obtained from slump tests, predict that aggregate normally used in concrete should not sink. To test this prediction, the settlement of a stone in fresh mortar is monitored. The stone does not sink in the undisturbed mortar (which has a high yield stress), but sinks when the mortar is vibrated, …

An Investigation On The Corrosion Potential Imaging At The Interface Of Concrete/Reinforcing Bar In Corrosion Media, Rong-Zong Hu, Chang-Jian Lin, Xiang Zhou, Jian-Guang Tan, Xiong-Chao Zhao

Journal of Electrochemistry

The iron array electrode covered with concrete as a new electrochemical technique is applied to map the potential imaging and to investigate on the iron electrode corrosion process under concrete: In Cl - solution the corrosion of the iron array electrode covered with concrete had been prevented for a short term since the concrete protection, but the corrosion still occurreed and developed after immersed for a long time. In SO 4 2- solution although the sample had being immersed for a long time and the concrete was possibly broken, the corrosion did not develop. In Cl - solution the corrosion …

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 …

Synthesis And Application Of Polymeric Corrosion Inhibitor For Reinforced Concrete, Weiwei Lin, Shengxian Wang, Jianqing Zhang

Journal of Electrochemistry

A new polymer E Twas synthesized and used as a corrosion inhibitor for reinforced concrete. The inhibitive behavior and mechanism were studied with linear polarization ,Tafel polarization,EIS and XPS method in simulated pore solution system with concrete samples.The result showed that the polymer was a mixing type inhibitor. A 1% dosage was sufficient to imhibit the corrosion of steel in simulated pore solution system. The salt endurance was enhanced from 0.02 mol/L to 0.10 mol/L.The result also showed the good synergetic effect of NaNO 2,especially in low NaNO 2 concentration.The EIS showed that E_T has dual function on reinforced concrete,i.e.,densifying …

Cure-State Monitoring And Water-To-Cement Ratio Determination Of Fresh Portland Cement-Based Materials Using Near-Field Microwave Techniques, Karl Joseph Bois, Aaron D. Benally, Paul S. Nowak, R. Zoughi

Electrical and Computer Engineering Faculty Research & Creative Works

Quick and nondestructive determination of curestate and water-to-cement (w/c) ratio in fresh Portland cementbased materials is an important issue in the construction industry since the compressive strength of these materials is significantly influenced by w/c ratio. This is especially true since current techniques are not reliable and require a priori testing of test specimens as calibration for subsequent on-site monitoring of a cast in-place structure. Recently, the sensing of Portland cementbased materials using microwave techniques has received much attention. Microwave nondestructive techniques have already shown the potential for determining w/c ratio, sand-to-cement (s/c) ratio and coarse aggregate-to-cement (ca/c) ratio in …

Testing Of Multi-Span Bridges With Full Span Precast Prestressed Concrete Panels (Phase 1), Robert J. Peterman, J. A. Ramirez

JTRP Technical Reports

The purpose of this study was to assess the behavior and durability of multi-span bridges constructed with full-span prestressed concrete form panels. The use of full-span prestressed concrete form panels for bridges with spans of 40 ft. or less is an economical method of construction due to the reduction of on-site formwork and labor required by alternate cast-in-place systems. In this research, a pair of two-span bridges utilizing full-span prestressed concrete form panels were fabricated and tested in the Karl H. Kettelhut Structural Engineering Laboratory at Purdue University. Time-dependent effects were monitored during the cast-in-place (CIP) concrete cure period of …

Elastic Modulus Of Concrete Affected By Elastic Moduli Of Mortar And Artificial Aggregate, Chung-Chia Yang, Yon-Yer Lin, Ran Huang

Journal of Marine Science and Technology

The effect of two artificial aggregate types and three kinds of mortar on the elastic modulus of concrete are reported. Bighteen batches of concrete with various volume fractions (10%, 20%, and 30%) were selected. Theoretical moduli were calculated based on micromechanics. Following recent studies of concrete as a twophase composite material, this study examines whether there is a relation between the elastic modulus of the constituents and concrete. From the examination of available experimental results, it is apparent that elastic modulus of concrete is affected by elastic modulus of constituents and volume fraction of aggregate. Test results were compared with …

Aggregate Effect On Elastic Moduli Ofcement-Based Composite Materials, C.C. Yang, R. Huang, W. Yeih, I.C. Sue

Journal of Marine Science and Technology

The elastic moduli of cement-based composite materials with different types of aggregates were investigated in this study. Twelve mixes with various volume fractions (10%, 20%, and 30% ) were selected. Cylindrical specimens with a dimension of ∮ 10 x 20 cm were cast and tested. Electric strain gages were used and elastic moduli were obtained from the stressstrain curves. Theoretical moduli were calculated based on H-S bounds and micromechanics. Test results show that the types and volume fractions of aggregates significantly affect the elastic moduli of concrete composite materials and the theoretical predictions fairly agree with the experimental data.

Examination Of Concrete Cores From Lowe’S Store In Bowling Green, David L. Allen, L. John Fleckenstein

Kentucky Transportation Center Research Report

The Kentucky Transportation Center was requested by Mr. Tom Brock, Vice President of McWhorter and Company, Inc., to examine cores obtained from a PCC floor slab of a Lowe's store in Bowling Green, Kentucky. From a telephone conversation with Mr. Brock, is was our understanding that a large portion of the surface of the floor slab was scaling and becoming detached. This apparently involved approximately the top 118 inch of the slab.

Nine cores were delivered to our laboratories. They were obtained at the locations shown in the floor map included in Appendix A. Those nine cores are shown in …

A Study Of Chloride Diffusion Properties Of Concrete At Early Age, W.D. Yeih, R. Huang, J.J. Chang

Journal of Marine Science and Technology

Existence of chloride ions in concrete may accelerate reinforcement corrosion. Chloride ions can penetrate into the concrete by the diffusion process even if no major cracks exist. It is well known that properties of concrete will change with time since the hydration reaction continues for a long time, which implies that the diffusion coefficient of concrete is a time-dependent function. In this research, the diffusion behavior is focused on early-age mortar and concrete. It is shown that the diffusion coefficient changes dramatically at early age; and the control of interface property is significantly important to chloride diffusion. The effect by …

Behavior Of Biaxially Loaded Concrete-Encased Composite Columns, Pedro Ricardo Munoz

Dissertations

The theory of nonlinear behavior of biaxially loaded short and slender composite columns is used to study the load-deformation and moment-curvature of four pin-ended composite column specimens tested under axial compressive load and biaxial bending moments in a single curvature. The accuracy of the test results is verified by comparison with analytical results obtained by a method of analysis that includes the nonlinear material properties of concrete and steel and covers the ascending and descending branches of the linear segmented column specimen. A computational method is presented to model the analytical behavior of the biaxially loaded composite column. Its validity …

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.

Roller Compacted Concrete For Highway Applications, Jorge Gomez-Dominguez

Indiana Local Technical Assistance Program (LTAP) Publications

A series of laboratory studies were carried out to investigate the behavior and characteristics of Roller Compacted Concrete (RCC) for highway applications.

Performance Survey Of Silicone-Sealed Concrete Pavement Joints, David Q. Hunsucker, Edgar E. Courtney

Kentucky Transportation Center Research Report

This report summarizes field inspections of various silicone-sealed concrete pavement joints. A list of silicone sealant projects was provided by the Kentucky Transportation Cabinet. Observations of performance were subjective and qualitative.

Bridge Decks And Overlays, James H. Havens, Theodore Hopwood Ii, Edgar E. Courtney

Kentucky Transportation Center Research Report

The report presents a historical perspective of the Transportation Cabinet's bridge deck construction and maintenance efforts directed toward increasing bridge deck durability.

Bridge decks crack in specific patterns that primarily depend upon bridge designs. Normal deck cracking is due to load-induced and thermal effects. Each type of cracking has a distinct pattern.

One-hundred and nineteen experimental bridge deck overlays were inspected. Included were 9 membrane bridges, 87 latex concrete overlays and 23 low-slump overlays. The overlays had been placed originally on both new and existing bridge decks on various routes throughout the state. Most of the overlays were rated in …

Shrinkage Compensation Deck Concrete (Ky 1974 Bridge Over Tates Creek Road), David Q. Hunsucker

Kentucky Transportation Center Research Report

This report summarizes the construction activities on an experimental bridge deck utilizing shrinkage compensating concrete. The experimental concrete is characterized in terms of freeze/thaw durability, compressive strength, and elastic moduli.

Physical And Mechanical Properties Of A New Type Of Polymer Concrete, Kyan Bin Khoo

Theses

A new type of Polymer concrete is an admixture of a special Latex, Portland cement and Sand. It has high bond strength, quick curing, durability and adequate strength. The Mechanical and Physical properties were investigated in this paper. Reinforcement with Glassfiber was done and its properties compared to those of control specimens. The heat generation in Polymer Concrete (PC) and its relationship with the properties of PC was also investigated.

A new type of Polymer concrete is an admixture of a special Latex, Portland cement and Sand. It has high bond strength, quick curing, durability and adequate strength. The Mechanical …

Optimization Analysis For Alignment Criteria And Installation Of Gravity Flow Underground Pipe, Eugene N. Balter

Retrospective Theses and Dissertations

In 1982 the Business Roundtable prepared several reports which investigated various aspects of construction which posed significant research opportunities. Their findings placed piping construction in the group of activities categorized as having "highest potential" for improvements based on inefficiency, or construction difficulty and proportionate costs. It was estimated that over $1 billion could be saved annually if the difficulty in the piping industry was improved to only average of other areas. Further investigation into the piping area showed that the alignment process took 20% of the cycle time for installation and ranked either first or second as compared to other …

Thickness Design Curves For Portland Cement Concrete Pavements, Herbert F. Southgate, Robert C. Deen

Kentucky Transportation Center Research Report

Past experience indicates that thickness designs using portland cement concrete best agree with criterion used in the Portland Cement Association's design method for 18-kip EAL of 2 to 3 million or less. For EALs greater than 2 to 3 million, past experience best agrees with criterion developed from the AASHO Road Test. Research herein indicates the two criterion become asymptotic to each other at approximately 2.5 million EAL. For a variation in thickness and elastic moduli in portland cement concrete, dense-graded aggregate, and sub grade elastic modulus, research indicates that a general conic equation (included herein) very closely duplicates the …

Low-Void Concrete Mixtures, Assaf S. Rahal, James H. Havens

Kentucky Transportation Center Research Report

The purpose of this study was to modify concrete mix-design formulas to supplant all water over and above that needed for hydration with a non-evaporable liquid material and(or) a super-water-reducer or plasticizer -- thus producing a low-void concrete. A water-cement ratio of 0.244 - 0.30 was presumed minimal for hydration of the cement. Several polymeric materials, asphalts, oils, and superplasticizers were used. Success was achieved with two latexes, one epoxy, and several superplasticizers. The use of these materials in concrete resulted in improved strength, reduction of air voids and permeability, and enhancement of resistance to corrosive chloride salts.

An Investigation Of Low Cylinder-Strengths (District 6), Assaf S. Rahal

Kentucky Transportation Center Research Report

District 6 has had a lingering problem of low cylinder-strengths. This report describes, in detail, an ensuing investigation which incorporated the use of identical materials of concretes used in District 6 and analyses of cylinder data, in situ concrete cores, and laboratory mixtures. The investigation revealed that a high percent of the in situ concrete is sound and reliable, and that aggregate type and (or) air content were not the cause for the low cylinder-strengths. The quality of making, storing, and curing the cylinders were the reasons for low-strength.

Freeze-And-Thaw Of Concretes And Aggregates, James H. Havens, Robert C. Deen

Kentucky Transportation Center Research Report

This report summarizes several years of research relating to damage to concrete and aggregates undergoing freezing and thawing. Basic principles involving freezing and attendant pressures are considered. Application of these principles to the evaluation of concrete was accomplished in experiments on concrete having low and high air contents. The effects of air entrainment upon freeze-thaw resistance were demonstrated.

Freeze-thaw characteristics of saturated aggregates relative to physical properties such as porosity, absorption, and bulk specific gravity were studied by submerging individual particles in pre-chilled mercury. Pressures associated with popouts in concrete were monitored and are presented along with accompanying theoretical considerations.

Voidless Concrete Mixtures For Bridge Decks, Assaf S. Rahal

Kentucky Transportation Center Research Report

The purpose of this study was to modify concrete mix-design formulas to supplant all water over and above that needed for hydration with a non-evaporable material -- thus producing a no-void concrete. It was adjudged that a water-cement ratio of 0.244 would be practical for hydration of the cement. Several polymeric materials, asphalts, and oils were used to replace the excess mixing water. Success was achieved using two latexes and one epoxy. The use of these materials in concrete resulted in improved strength, reduction of air voids and permeability, and enhancement of resistance to corrosive chloride salts.

An Evaluation Of In-Stream Structures Designed To Provide Fish Habitat, Charles H. Call Jr.

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

In-stream concrete structures were studied through model tests and river tests. The model studies indicated that four designs provided good habitat in the model stream. These structures were the inverted weir, the "V" structure, the slab with legs and the cylinder. Through the river studies it was determined that these structures did not influence enough of the total river area to be effective in providing good fish habitat. Also an appreciable amount of yearly maintenance would be required to free the structures from silting in, debris, and vandalism. The slab with legs was the only promising structure.

Construction, Protection And Maintenance Of Concrete Bridge Decks, Ronald D. Hughes, James H. Havens

Kentucky Transportation Center Research Report

This report presents an historical account of deterioration in reinforced concrete bridge decks. Preventative maintenance treatments to both new and in-service decks are discussed. Repair methods are included. The major forms of deterioration are listed and causative mechanisms are discussed. Potential design and construction remedies are presented for consideration.

Durability Of Traffic Paint On Portland Cement Concrete Pavements, Assaf S. Rahal

Kentucky Transportation Center Research Report

Performance of a series of transverse lines applied to a relatively new concrete pavement, utilizing primes and pretreatments, is reported. The report includes descriptions of the location of test lines and types of paint and pretreatments, performance histories, and analysis of results. Chlorinated rubber, epoxy, and urethane paints were the most durable. Neither pretreatment nor the use of primes significantly increased durability.