Evaluation and Load Testing of Posttensioned Concrete Structure Exhibiting Distress
Publication: Journal of Performance of Constructed Facilities
Volume 30, Issue 1
Abstract
This article discusses the evaluation of a posttensioned concrete structure exhibiting cracking using nondestructive evaluation, laboratory testing of concrete samples, and subsequent in situ load testing. During a field survey, it was identified that the posttensioned beams exhibited visually apparent deflections. An engineering evaluation was initiated to identify the cause of this type of cracking in the posttensioned structural system. Following a field survey and document review, an analysis was initiated for the estimation of potential posttension losses and analytical expected deflections for the purposes of comparing it to measured deflections in the field. After the analytical phase, an in situ, nondestructive evaluation phase and a subsequent material testing phase were initiated. The in situ evaluation of the structure involved nondestructive testing of concrete slabs and beams using ground-penetrating radar (GPR) to locate tendons. Cores were removed, and compressive strength testing and petrographic analysis of the cores were performed in the laboratory. Based on the review of the findings of the engineering analysis, nondestructive evaluation, and laboratory testing, the concrete beams and slabs were load-tested in accordance with ACI 318, Chapter 20. The load test served to verify that the structure could safely sustain the service load requirements of the building code. This paper should be of value to consulting engineers engaged in condition assessment of posttensioned structures exhibiting distress, in terms of the test methods used and the methodology used in developing various aspects of the load-testing program.
Get full access to this article
View all available purchase options and get full access to this article.
References
ACI (American Concrete Institute). (2008). “Building code requirements for structural concrete and commentary.”, Farmington Hills, MI.
ASTM. (2004). “Standard practice for petrographic examination of hardened concrete.” C 856, West Conshohocken, PA.
ASTM. (2010a). “Standard test method for compressive strength of cylindrical concrete specimens.” C 39, West Conshohocken, PA.
ASTM. (2010b). “Standard test method for obtaining and testing drilled cores and sawed beams of concrete.” C 42, West Conshohocken, PA.
Information & Authors
Information
Published In
Copyright
© 2014 American Society of Civil Engineers.
History
Received: Dec 11, 2013
Accepted: Sep 29, 2014
Published online: Dec 5, 2014
Discussion open until: May 5, 2015
Published in print: Feb 1, 2016
Authors
Metrics & Citations
Metrics
Citations
Download citation
If you have the appropriate software installed, you can download article citation data to the citation manager of your choice. Simply select your manager software from the list below and click Download.