ACI Global Home Middle East Region Portal Western Europe Region Portal
Email Address is required Invalid Email Address
In today’s market, it is imperative to be knowledgeable and have an edge over the competition. ACI members have it…they are engaged, informed, and stay up to date by taking advantage of benefits that ACI membership provides them.
Read more about membership
Learn More
Become an ACI Member
Topics In Concrete
Home > Publications > International Concrete Abstracts Portal
The International Concrete Abstracts Portal is an ACI led collaboration with leading technical organizations from within the international concrete industry and offers the most comprehensive collection of published concrete abstracts.
Showing 1-5 of 91 Abstracts search results
Document:
SP128-54
Date:
November 1, 1991
Author(s):
H. Mugurumu
Publication:
Symposium Papers
Volume:
128
Abstract:
The authors had tested eight square reinforced concrete columns subjected to combined flexure and constant axial loads of 0.254 to 0.629 f'?c A?g, and the test results were reported in a previous paper. This study is a continuation of that previous study. The objective of this study is to evaluate the ductility enhancement of high-strength concrete columns achieved by effectively confining the core concrete using transverse reinforcement with high yield strength. Four test columns were constructed using concrete with compressive strength of 130 MPa, transverse reinforcement with yield strength of 408 or 873 MPa, and ordinary longitudinal reinforcement. Those columns tested under reversed cyclic lateral loads with constant axial compressive load levels of 0.343 or 0.473. Test results indicated that even for such high-strength concrete columns adequate ductility was secured by using high-strength transverse reinforcement. Based on the test results, the stress-strain model on confined concrete previously proposed by the authors was modified to be applicable not only to ordinary strength concrete but also to high-strength concrete
DOI:
10.14359/2871
SP128-67
Chil-Lim Park, and Sung Won Yoon
This paper deals with a new type of semiprefabricated slab. The slab is made of precast thin slab stiffened by a set of folded wire fabric including cast in-situ topping concrete. This study covers both the salient features of design and construction of this flooring system and experimental work carried out to study the flexural behavior of the slabs cast using the system. The results of the experiment showed that composite precast slab consisting of the precast thin slab and in-situ topping concrete can be designed as a monolithic component.
10.14359/2344
SP128-07
Hemant S. Limaye and Donald F. Meinheit
Over the last 3 years, an impact-echo technique has proven to be an effective evaluation tool in identifying defects and locating embedded items in concrete structures. The advantages of the method are that it is nondestructive, relatively easy to calibrate, and testing can be conducted from one surface of the element under test. Operating experience with the impact-echo technique has shown that, within known limitations, the technique can provide a rapid nondestructive means for performing certain concrete condition surveys.
10.14359/3636
SP128-09
M. Sansalone, Y. Lin, D. Pratt, and C. C. Cheng
This paper summarizes recent developments in the impact-echo technique for locating defects in concrete structures. First, the impact-echo principle is reviewed and frequency analysis of impact-echo signals is explained for those unfamiliar with the technique. Advancements in signal processing that have been aimed at simplifying and automating data interpretation are discussed, and examples from the use of an artificial-intelligence technique for automated interpretation of signals from plate-like structures are shown. Impact-echo instrumentation is reviewed and an impact-echo field system is described. The newest application for the method is testing bar-like structures, such as columns and beams. Numerical and experimental controlled-flaw studies established the basis for the use of impact-echo for this application. Representative results obtained from impact-echo studies carried out on reinforced concrete columns with circular and rectangular cross sections are presented. Finally, an overview of ongoing research is presented.
10.14359/3639
SP128-04
N. A. Cumming, P. T. Seabrook, and V. Malhotra
A research program was undertaken to evaluate commercially available nondestructive testing techniques to locate voids in grouted tendon ducts. A laboratory scale mockup was used to evaluate several methods. On the basis of these results, impact-echo, ultrasonic, pulse-echo, and ultrasonic pitch-catch systems were selected for further evaluation. A full-scale mockup of a section representing an icewall of an offshore drilling structure was fabricated. It contained grouted tendon ducts with voids of various sizes and configuration. A test was carried out in which three teams of researchers from Canada and the U.S. evaluated nondestructively the mockup without knowledge of the locations or nature of the voids. This paper presents the results of the preceding evaluation and makes recommendations for further research.
10.14359/3648
Results Per Page 5 10 15 20 25 50 100
Edit Module Settings to define Page Content Reviewer