Engineering Commons^™

Compressive Strength, Free Expansion And Shrinkage Of Expansive Concrete Containing Fly Ash, Warangkana Saengsoy, Rachot Chatchawan, Somnuk Tangtermsirikul

International Conference on Durability of Concrete Structures

This study is aimed to investigate effect of fly ash on compressive strength, free expansion and shrinkage of expansive concrete. High CaO and low CaO fly ashes are used in this study. The replacement percentages of total binders by fly ash are 0 and 30% by weight. The replacements of expansive additive are 0, 20 and 30 kg/m³ of concrete. The test results revealed that the use of fly ash especially the high CaO fly ash can enhance expansion of expansive concrete at early age. The use of fly ash also reduces shrinkage at long term of the expansive …

Effects Of Nano-Caco3 On The Properties Of Cement Paste: Hardening Process And Shrinkage At Different Humidity Levels, Yamei Cai, Pengkun Hou, Zonghui Zhou, Xin Cheng

International Conference on Durability of Concrete Structures

The hardening process and volume stability of cement pastes with and without nano-CaCO₃ (NC) were studied through investigations on the setting time and shrinkage. Results showed that NC shortened the setting time of cement paste: the initial setting time decreased by 3.9 and 11.1% when 1 and 3% NC were added, and the finial setting times were shortened by 6.2 and 15.2%, respectively. The shrinkage of cement paste was compensated by NC, and the effect was more obvious as more NC was added into the cement paste. Although the shrinkage decreased at the lower relative humidity, the degree of …

Effect Of Cured Time On Creep Of Lightweight Aggregate Concrete, Hongzhi Cui, Haibin Yang, Xiaoxiao Xu, Zitao Lin, Tommy Yiu Lo

International Conference on Durability of Concrete Structures

Creep and shrinkage are such properties that will occur in concrete when they are under load and exposed to surrounding. Since this property will cause deformation which may decrease the design strength of the concrete, it is necessary to do have more knowledge on this phenomenon. So, we will study the effect of creep on 7 and 14 days of cured time of specimens which sealed or unsealed will be considered, respectively. The specimens have shown how the concrete strains when they are under sustained load with time. Besides, the sealed specimens have shown how the basic creep is different …

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 …

High-Performance Concrete Bridge Decks: A Fast-Track Implementation Study Volume 2: Materials, Mateusz Radlinski, Jan Olek

JTRP Technical Reports

The purpose of this research was to examine the applicability of ternary binder systems containing ordinary portland cement (OPC), class C fly ash (FA) and silica fume (SF) for bridge deck concrete. This was accomplished in two parts, the laboratory part and a field application part.

During the laboratory studies, four ternary mixtures, each containing either 20% or 30% FA and either 5% or 7% SF were subjected to four different curing regimes (air drying, 7 days curing compound application and 3 or 7 days wet burlap curing). In general, all four ternary mixtures exhibited very good water and chloride …

High-Performance Concrete Bridge Decks: A Fast-Track Implementation Study, Volume 1: Structural Behavior, Robert J. Frosch, Timothy S. Aldridge

JTRP Technical Reports

Transverse cracking of concrete bridge decks is problematic in numerous states. Cracking has been identified in the negative and positive moment regions of bridges and can appear shortly after opening the structure to live loads. To improve the service life of the bridge deck as well as decrease maintenance costs, changes to current construction practices in Indiana are being considered. A typical bridge deck was instrumented which incorporated the following: increased reinforcement amounts, decreasing reinforcement spacing, and high-performance, low-shrinkage concrete. The low shrinkage concrete was achieved using a ternary concrete mix. The objective of this research was to determine the …

Design Methods For The Control Of Restrained Shrinkage Cracking, Robert J. Frosch, Jacob Kenyon Bice, Jared Bruce Erickson

JTRP Technical Reports

Cracking in concrete bridge decks can result in increased susceptibility to deterioration. As cracks provide direct routes for the ingress of deleterious elements to the reinforcement and superstructure, cracking can lead to reduced service lives for bridge structures. Several factors affect the extent of cracks which develop in bridge decks; however, relatively few are within the control of the designer. The objective of this research was to evaluate the influence of design parameters on the performance of bridge decks with respect to cracking and to develop simple design tools that are appropriate for both steel and nonmetallic reinforcement. This research …

Evaluation Of Rapid Setting Cement-Based Materials For Patching And Repair, Amit D. Barde, Swathi Parameswaran, Todd Chariton, W. Jason Weiss, Menashi D. Cohen, Scott Andrew Newbolds

JTRP Technical Reports

The efficient repair and replacement of concrete pavements and bridge decks often requires a rapid setting material that can be placed, cured, and opened to traffic in a relatively short period of time. Frequently, temporary repairs are made using materials that are later found to be incompatible with the existing pavement, structures, and environment. This practice causes these materials to fail prematurely, frequently requiring re-repair. Research is needed to determine which rapid setting repair materials demonstrate the best behavior with rapid strength gain, low potential for cracking, and excellent durability. The objective of this research is to evaluate the performance …

Investigation Of Bridge Deck Cracking In Various Bridge Superstructure Systems, Robert J. Frosch, David Todd Blackman, Roger Dwight Radabaugh

JTRP Technical Reports

Many bridges in the state of Indiana have been identified to have cracking in the concrete deck. Cracking has been identified in the negative and positive moment regions of bridges on both the top and bottom surfaces and can appear before or shortly after the opening of the structure to live loads. Significant crack widths and various degrees of cracking exist in different bridge systems including both concrete and steel superstructures. This research project was divided into five phases to determine the factors affecting transverse and longitudinal bridge deck cracking, as well as, to develop design recommendations that minimize or …

Performance-Related Specifications For Concrete Bridge Superstructures, Volume 2: High-Performance Concrete, J. Olek, Aijsing Lu, Xiuping Feng, Bryan Magee

JTRP Technical Reports

This is Volume 2 of the Final Report for the project titled “Performance-Related Specifications for Concrete-Bridge Superstructures” dealing with the topic of High-Performance Concrete (HPC). The investigation of high-performance concrete included the development of optimized concrete mixtures and identifying their performance characteristics related to durability for the purpose of using these characteristics in performance–related specifications in the state of Indiana. The research effort described in this report was divided in two phases. Phase I was focused on development of concrete mixtures optimized with respect to selected performance-related parameters. During this phase, ten optimum concrete mixes have been identified from 45 …

Examination Of Post-Tensioned Steel Bridges In Indiana, Hung-I Wu, Mark D. Bowman

JTRP Technical Reports

The purpose of the research study is to conduct an investigation to understand the performance of a relatively new type of bridge construction that involves prestressed (post-tensioned) steel-concrete composite bridge members. Strictly speaking, the technical and economical advantages of this type of structure have been understood for several decades. However, the application of this concept to practice is still very limited due to difficulties associated with the post-tensioning anchorage. The study was thus intended to explore the mechanical behavior of such construction. Both the short-term and long-term bridge performance were evaluated in this study.

The investigation included experimental as well …