Performance of Lap Splices in Large Scale Column



1.1 PROBLEM STATEMENT Over the past 25 years or so, the Texas Department of Transportation (TxDOT) has had an aggressive construction program in place to accommodate the expanding population growth within Texas. A significant amount of construction has occurred throughout the state, especially in major metropolitan areas. Because of constrained conditions in metropolitan areas in terms of access space and the raw scale of transportation systems needed to satisfy the increasing traffic demands, the size of transportation structures, both at the member and system levels, have become significantly larger than past construction. Unlike nominal-size concrete placements, large concrete placements can experience elevated temperatures during hydration, which can later lead to cracking and deterioration of these concrete structures.

Moreover, contractors have taken aggressive approaches in the construction of such structures to meet the construction demands in these metropolitan areas. In addition to aggressive scheduling and resource allocations, some contractors are believed to have proportioned concrete mixtures with early set cement (Type III) to achieve high early strengths. This way, the forms can be removed more quickly, thus expediting the completion of construction. Although advantageous in minimizing construction costs and build time, this practice may have contributed to the early cracking of many structures (termed premature concrete deterioration).







PERFORMANCE OF LAP SPLICES IN LARGE-SCALE COLUMN SPECIMENS AFFECTED BY ASR AND/OR DEF

by

Joseph M. Bracci, Paolo Gardoni, M. Kathleen Eck, and David Trejo

Zachry Department of Civil Engineering and Texas Transportation Institute


Report 0-5722-1 Project 0-5722

Project Title: Lap Splice and Development Length Performance in ASR and/or DEF Damaged Concrete Elements


Performed in cooperation with the Texas Department of Transportation

and the Federal Highway Administration


Published: June 2012

TEXAS TRANSPORTATION INSTITUTE The Texas A&M University System College Station, Texas 77843-3135


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