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
Founded in 1904 and headquartered in Farmington Hills, Michigan, USA, the American Concrete Institute is a leading authority and resource worldwide for the development, dissemination, and adoption of its consensus-based standards, technical resources, educational programs, and proven expertise for individuals and organizations involved in concrete design, construction, and materials, who share a commitment to pursuing the best use of concrete.
Staff Directory
ACI World Headquarters 38800 Country Club Dr. Farmington Hills, MI 48331-3439 USA Phone: 1.248.848.3800 Fax: 1.248.848.3701
ACI Middle East Regional Office Second Floor, Office #207 The Offices 2 Building, One Central Dubai World Trade Center Complex Dubai, UAE Phone: +971.4.516.3208 & 3209
ACI Resource Center Southern California Midwest Mid Atlantic
Feedback via Email Phone: 1.248.848.3800
ACI Global Home Middle East Region Portal Western Europe Region Portal
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 17 Abstracts search results
Document:
SP231-05
Date:
October 1, 2005
Author(s):
K.W. Kramer
Publication:
Symposium Papers
Volume:
231
Abstract:
A survey of the first uses of precast, prestressed or post-tensioned foldedplates roofs show that this structural system start in the 1950’s and end in the 1970’s Ahistoric perspective of this structural system will be presented starting in the 1950’s andending in the 1970’s. While prestressed concrete was making a break-through in theUnited States with the Walnut Lane Bridge in Philadelphia, PA, Europe was usingprestressed concrete in various types of structural systems. One of these systems wasthe folded plate roof system. Approximately a decade later in the United States, theCloverleaf Lanes Bowling Alley in Dade County, Florida used the same application inwhich the corrugated slab spanned 120 feet and extending transversely 286 feet. In1962, this system of folded plate shells went from long span structures to being used inroof structures for dormitories at Washington State University. The main beams for thedormitories were pretensioned in a factory, while the secondary beams were post-tensioned on site. During the 1970’s, precast folded plate structures were beingconstructed throughout the United States for various types of buildings, one notablestructure is the Hangar for Allegheny Airlines at Logan Airport, Boston, Massachusetts.Then they disappeared in the United States. Some Possible reasons why folded plateconstruction stopped are numerous but the two main factors are the architecturalsolution, and the lack of understanding of folded plate structures on the part ofengineers and architects.
DOI:
10.14359/14921
SP231-04
W.N. Marianos, Jr.
The growth of prestressed concrete development in the United States wasgreatly influenced by the publications available to practicing engineers. A number ofthe early books and publications on prestressed concrete are reviewed and discussedin this paper. Pioneers of prestressed concrete development are viewed through theirpublications and the role they played in promoting prestressing. Two key conferences(in 1951 and 1957) are also considered. Figures include samples of important passagesfrom the texts considered. Through all of these, some of the flavor and personalities ofthis important period can be experienced.
10.14359/14920
SP231-03
A. Schokker
Prestressed concrete is a relatively young form of construction in the UnitedStates. The development of the various types of prestressing materials, includinganchorages was critical to the success of prestressed concrete as we know it today.This paper reviews the history of prestressed concrete with a focus on post-tensioningrelated patents in both the United States and abroad. Early patents from 1945 andonward are included up through the present day. The 1950’s and 1960’s are a primaryfocus as the decades where prestressed concrete was taking a foothold in the UnitedStates.
10.14359/14919
SP231-09
J.F. Stanton
In post-tensioned systems, friction during stressing and slip-back due tosetting the wedge anchors cause loss of prestress. If the tendon is long or containssharp curvatures, these losses can be significant. This paper summarizes methods forcalculating the losses and provides an evaluation of the numerical coefficientssuggested by ACI 318-05 for friction. Equations are provided where closed formmethods are possible, and numerical methods are outlined for other cases.
10.14359/14925
SP231-08
P.R. Gupta
Friction losses contribute about 50% of the total losses in post-tensionedconstruction. The original loss coefficients that were derived for earlier post-tensioningsystems are still being used in the ACI recommendations for unbonded construction.Some of these systems have not been used in the industry for almost 30 years.This paper presents a review of the current ACI recommendations of friction losses inunbonded construction. The paper also describes the theoretical development of asimple field technique to determine the curvature and wobble coefficients under fieldconditions. Results from initial testing are compared with the ACI recommendations andindustry practice.
10.14359/14924
Results Per Page 5 10 15 20 25 50 100