Softened Strut-and-Tie Model for Shear and Flexural Strengths of Reinforced Concrete Pile Caps
Publication: Journal of Structural Engineering
Volume 147, Issue 11
Abstract
Reinforced concrete pile caps are important structural elements transmitting vertical loads from the structure to the ground. The performance of pile caps is complex, with a wide range of structural parameters in play, such as geometry, tension reinforcement, pile arrangement, and so on. Their complexity and criticality demand a good degree of reliability in strength estimations. Current design approaches are devoid of contribution from key parameters, resulting in inaccurate strength estimations. Moreover, there are interpretation difficulties when using the existing code provisions for members with pile arrangements that are not too simple. A general approach considering the influence of critical parameters for estimating the strength of pile caps in shear and flexure is proposed in this paper. The proposed approach can capture the accurate contribution of nondominant load paths, typically observed in pile caps with nonsymmetric pile arrangements. The model predictions for 21 specimens with varying parameters and failure modes are compared with test strengths and American design code (ACI) code estimations. Results showed an excellent correlation with test results, better than code estimations, showing the accuracy and efficacy of the proposed model.
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Data Availability Statement
Some or all data, models, or code that support the findings of this study are available from the corresponding author upon reasonable request. Such data include the exact values of pile cap capacities calculated through the code, as well as the cracked and ultimate deformations of struts in all pile cap specimens calculated according to the proposed analytical model.
Acknowledgments
The support from the National Center for Research on Earthquake Engineering, Taiwan, under Project No. 06105C9029 and the support from the Ministry of Science and Technology, Taiwan, under Grant No. 109-2811-E-002-527 are gratefully acknowledged. The authors would also like to acknowledge the help of Mr. Sheng-Jie Jhuang, a master student from National Taiwan University, in verifying the strength calculations presented in this paper.
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Published In
Journal of Structural Engineering
Volume 147 • Issue 11 • November 2021
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© 2021 American Society of Civil Engineers.
History
Received: Aug 27, 2020
Accepted: Jun 2, 2021
Published online: Aug 20, 2021
Published in print: Nov 1, 2021
Discussion open until: Jan 20, 2022
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