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International Concrete Abstracts Portal

Showing 1-5 of 10 Abstracts search results

Document: 

SP338

Date: 

April 27, 2020

Author(s):

Bruce A. Suprenant and Oscar R. Antommattei

Publication:

Symposium Papers

Volume:

338

Abstract:

Ward R. Malisch spent most of his 50-year career addressing issues related to concrete construction, specifically to problems that concrete contractors deal with daily. His civil engineering training began at the University of Illinois at Urbana-Champaign where he received his BS, MS, and PhD in 1961, 1963, and 1966, respectively. During his time at Illinois he also carried out research on concrete durability and taught courses on plain concrete. Following that, he taught courses in concrete construction at the University of Missouri-Rolla (now Missouri University of Science and Technology) where he received several awards for outstanding teaching. During his time there he took a leave of absence to work in quality control for the prime contractor building Missouri’s first nuclear power plant. This experience spurred his interest in how specification requirements and tolerances affected contractors’ abilities to build both simple and complex structures. Malisch was able to reach the construction industry more directly when he joined the staff of the World of Concrete seminar program and later became editor of Concrete Construction magazine. He was then able to teach at a national level by further developing a seminar program and editorial content that featured how-to-do-it information on concrete technology, with an emphasis on contractor-related topics. During his tenure with the magazine, he began answering questions on a telephone hotline service offered by the American Society of Concrete Contractors (ASCC), and gave advice on problems related to unrealistic concrete tolerances, inadequate knowledge about plastic concrete properties, ambiguous specifications, and a wide range of other construction-related topics. In subsequent years, Malisch served as director of engineering and later as senior managing director at the American Concrete Institute. There, while supervising the engineering, marketing, and education departments, and serving as publisher of Concrete International magazine, he also interacted with other concrete-related organizations, serving on the Research, Engineering, and Standards Committee of the National Ready Mixed Concrete Association and on the ASCC Board of Directors. Along with the ACI Strategic Development Council, ASCC, and Construction Technology Laboratories, he helped to organize an Inter-Industry Working Group on Concrete Floor Issues that brought together leaders from several construction and flooring industry groups. One outcome of this group’s activity was publication of ACI 302.2R-06, “Guide for Concrete Slabs that Receive Moisture-Sensitive Flooring Materials.” Upon retirement from ACI in 2008, he was named technical director of ASCC. He was active again in forming an Inter-Industry Working Group on Reducing the Cost of Tolerance Compatibility Problems along with eight other co-sponsoring groups. He later served as principal investigator on two construction related research projects dealing with contractor-related problems. Dr. Malisch’s awards include: • 1986— Elected Fellow of the American Concrete Institute • 2004— Arthur Y. Moy Award, ACI Greater Michigan Chapter • 2006— Silver Hard Hat Award, highest award given by the Construction Writers Association • 2008— Richard D. Gaynor Award, Highest technical award given by the National Ready-Mixed Concrete Association • 2009—One of Concrete Construction magazine’s Most Influential People • 2010— Arthur R. Anderson Medal, ACI, given for outstanding contributions to the advancement of knowledge of concrete as a construction material • 2011— ACI Construction Award, given to the author of any paper of outstanding merit on concrete construction practice • 2011— ASCC Lifetime Achievement Award, ASCC’s highest honor, acknowledging recipients for their body of work within the industry and their service to ASCC • 2013— ACI Honorary member, given to a person of eminence in the field of the Institute’s interest or one who has performed extraordinary meritorious service to the Institute • 2019—Roger H. Corbetta Concrete Construction Award, ACI, given to an individual that has made significant contributions to progress in methods of concrete construction. For his dedication to the concrete construction industry, this Special Publication is a tribute to his work and is sponsored by the ACI Construction Liaison Committee. Sixteen presentations, distributed in four sessions named “Ward R. Malisch Concrete Construction Symposium,” were given at the 2017 ACI Fall Convention in Anaheim, CA. The quality of the presentations was highlighted by the participation of four former presidents of ACI: David Darwin, Terry Holland, Ken Hover and Mike Schneider. The nine manuscripts presented in this Special Publication are significant in that each paper represents authors that have been previously published in ACI. Thanks are extended to the many ACI members who reviewed the manuscripts and provided helpful technical and editorial comments which enhanced the authors’ papers. This Special Publication is but one small token of appreciation and gratitude to the more than 50-year service of Ward R. Malisch to concrete construction. He has been a source of inspiration to many as well as an example of honesty, integrity, and dedication. He has built the foundation for others to build upon in serving the concrete construction industry.

DOI:

10.14359/51725830


Document: 

SP-338_09

Date: 

March 1, 2020

Author(s):

Eldon Tipping and Bryan M. Birdwell

Publication:

Symposium Papers

Volume:

338

Abstract:

This is the third of a three-part series, the goal of which is to provide the designer and contractor with tools necessary to produce level deflected slabs on metal deck. This third part provides the designer and contractor with strategies for producing level deflected slabs on metal deck. An approach by which elevation tolerances can be successfully imposed on the erected steel frame is presented. The method requires that the designer first provide the contractor with desired relative elevation of splice points at each floor level and flexible column splice details. This information, provided by the designer, enables the contractor to establish desired relative elevations that can assist in achieving those tolerances. An effective cambering strategy that recognizes the differing behavior of members framing to columns and those that connect to girders is presented and discussed. The paper finally presents a floor construction/monitoring program that identifies frame behavior during construction and provides both the designer and contractor with the resources necessary to produce level deflected slabs. The program includes pre- and postplacement surveys of structural steel frame, utilization of a controlled method of striking off the concrete, a survey of the completed slab surface, and use of the collected data to respond to unexpected structural behavior. Other tools, including the selective use of “loose shores” or a secondary placement can enable the contractor to produce deflected slabs on metal deck with 80% or more of the surface within a 3/4 inch (19 mm) deep envelope.

DOI:

10.14359/51724730


Document: 

SP-338_08

Date: 

March 1, 2020

Author(s):

Eldon Tipping and Bryan M. Birdwell

Publication:

Symposium Papers

Volume:

338

Abstract:

This is the second of a three-part series, the goal of which is to provide the designer and contractor with tools necessary to produce level deflected slabs on metal deck. This second part explores the role ineffective and incorrect use of ACI and AISC documents plays in designer attempts to provide his client with level deflected slabs on metal deck. Project documents often incorrectly reference ACI guide documents such as ACI 302, attempting to make their content mandatory, when that is not intended by ACI. The ACI prohibition of using guide document content without restating in mandatory language is presented and discussed. Reference is often made in design documents to the AISC Code of Standard Practice for floor elevation when the Code is silent concerning the elevation of all elements excepting that of column base plate elevation. AISC tolerances impacting floor levelness are presented and discussed. Virtually all supporting structural steel floor framing systems are comprised of a collection of secondary members (beams) which transfer gravity loads to primary members (girders) which ultimately transfer these gravity loads to vertical elements and finally to foundations. The collection of floor framing members contains some combination of un-cambered steel beams/girders and those with fabricated camber to off-set anticipated deflection of the member when subjected to the weight of concrete. The deflection of those members will vary depending on member stiffness and the resistance of connections to end rotation. The ineffectiveness of the common designer requirement that concrete be added until “the floor is level” is presented and discussed in detail.

DOI:

10.14359/51724729


Document: 

SP-338_05

Date: 

March 1, 2020

Author(s):

Ronald Kozikowski and Kevin Rowswell

Publication:

Symposium Papers

Volume:

338

Abstract:

Several documents have indicated that applying curing water cooler than the concrete surface by more than 20⁰ F (11⁰ C) can produce a strain of about 100 millionths, exceeding the concrete’s strain capacity, and resulting in cracking. Earlier work by the senior author and others has questioned the origin and applicability of the 100 millionths strain capacity for early-age concrete. Tests on small-scale specimens demonstrated that using curing water as much as 55⁰ F (34⁰ C) cooler than the concrete surface did not result in crazing or cracking. This paper describes a study in which cold curing water was used on a large concrete slab under field conditions. Experimental results suggest that at least a 50°F (32°C) temperature difference between curing water and a concrete slab can be withstood without causing surface crazing or cracking.

DOI:

10.14359/51724726


Document: 

SP-338_02

Date: 

March 1, 2020

Author(s):

Kenneth C. Hover

Publication:

Symposium Papers

Volume:

338

Abstract:

PCA researchers interested in the problem of evaporation of bleed water from concrete surfaces borrowed an equation developed by hydrologists to predict evaporation from Lake Hefner in Oklahoma. PCA’s graphical representation of that equation, subsequently modified to its present form by NRMCA, was later incorporated into multiple ACI documents, and is known by concrete technologists world-wide as the “Evaporation Rate Nomograph.” The most appropriate use of this formulation in concrete construction is to estimate the evaporative potential of atmospheric conditions (known as “evaporativity”). Since the difference between actual and estimated evaporation rate can be in the range of ± 40% of the estimate, best use of the equation as routinely applied is as a semi-quantitative guide to estimate risk of early drying and inform decisions about timing and conduct of concrete placing and finishing operations. Use of the “Nomograph” and related “Apps” in specifications is more problematic, however, given: 1.) the inherent uncertainty in its underlying equation, 2.) the difficulty in obtaining input data that appropriately characterize jobsite microclimate, and 3.) establishing a mixture-specific criterion for tolerable evaporation rate.

DOI:

10.14359/51724723


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