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
Showing 1-5 of 15 Abstracts search results
Document:
SP87-07
Date:
September 1, 1985
Author(s):
Arthur H. Nilson
Publication:
Symposium Papers
Volume:
87
Abstract:
Research at Cornell University over an eight, year period, on concrete with comprehensive strenght in the range from 6000 to 12,000psi 41-83MPa) has established a good basic for understanding the fundamental nature of the material and has also provided information on engineering properties such as moduls of elatisity, tensile strength, creep coeficient possion, ratio, rate of strength gain with age, and strain limit values. Some of these are reviewed briefly. The main purpose of the paper is to summarize more recent Cornell research dealing with the behavior of reinforced and prestressed concrete structural members, made using high strength concrete. Test have included axially-loaded members with varying amounts of spiral confinment steel, flexural critical beams with varying amounts of tensile and compressive reinforcement, and stirupps, reinforced concrete beams under sastained load of 3 years duration, shear critical reinforced concrete beams. It was found that while many provisions of the 1983 ACI code are applicable to high strength concrete materials and members certain code provisions must be reexamined, modified, or limited to insure structural saftey and servability.
DOI:
10.14359/6526
SP87-08
R. N. Swamy
The paper presents a comprehensive review of the material properties and structural behavior of high strength concrete. It is shown that in practice both early development of high strength and high final strength are desirable. Further, if such concretes are to be used economically, a high proportion of their strength needs to be utilised in design. Data are presented to show that by careful selection of the type of cement and design of mix proportions, strengths of 60 to 80 N/mm2 could be obtained with normal weight aggregates in 24 hrs. With light-weight aggregates, strengths of LO-25 N/mm2 in 12 hrs. and of 25-45 N/mm2 in 24 hrs. are reported. The paper then discusses the engineering properties of such concretes such as elasticity, shrinkage and creep. The implications on structural behavior, when high working stresses of 30 to 50% of the cube strength are used, are then discussed in terms of transmission length, prestress losses, short term structural behavior and longterm structural behavior. Particular emphasis is given to those aspects that need to be considered in design.
10.14359/6527
SP87-13
Antoine E. Naaman and Joseph R. Homrich
The use of high strength concrete is attractive in precast prestressed concrete structures and in earthquake resistant structures for which a reduction in mass is of paramount importance. Yet applications of high strength concrete are hindered by its relative brittleness. Such a drawback can be overcome by addition of fibers. The present study describes the main effects of fiber reinforcement on the compressive stress-strain properties of high strength fiber reinforced mortar and concrete. The influence of various fiber reinforcing parameters such as volume fraction of fibers, aspect ratio, and type of fibers is illustrated. Trade-offs to achieve ductility while maintaining high strength are explained.
10.14359/6532
SP87-14
Robert C. Chen, Ramon L. Carrasquillo, and David W. Fowler
Experimental investigations on the behavior of high strength concrete under uniaxial and biaxial short-term compressive stresses were conducted using thin square plate specimens. Strength, stress-strain relationship, mode of failure, and failure mechanism are discussed. Results confirm that a main cause of the increase in strength, stiffness, and proportional limit of concrete under biaxial compression is the confinement of internal microcracking preventing the development of a progressive failure mechanism. In addition, it was found that as the aggregate stiffness approaches that of the mortar, both the proportional limit and the discontinuity point of the concrete increase due to the reduction of stress concentrations. The observed failure mode for high strength concrete can be explained in terms of the limiting tensile strain criterion.
10.14359/6533
SP87
Editor: Henry G. Russell
SP87 High-strength concretes are used frequently in applications requiring slender members to carry large loads or span long distances. Early applications of high-strength concrete emphasized its use to reduce column dimensions. More recently, high-strength concrete has been used to meet special project objectives such as large composite columns and stiffer structures. In turn, the use of high-strength concrete has prompted the applications of more stringent quality control requirements. This publication highlights the use, design implications, and research results of applications of high-strength concrete.
10.14359/14044
Results Per Page 5 10 15 20 25 50 100
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.
Edit Module Settings to define Page Content Reviewer