Testing and Evaluation of Frictional Lose for Strand with Multi-Curves

Abstract:

How to determinate the pre-stressing losses is a key issue for the pre-stressed concrete structure design and construction. Especially for the major engineering projects, the actual value of pre-stressing loss should be detected in site to check or revise the original design parameters and keep the engineering in safety. Compared with the straight strand, the frictional lose between strand with multi-curves and ducts would occupy the most part of all losses. It is a crucial ingredient to determinate the pre-stressing losses. This paper introduces the detection and evaluation results about frictional loss of a typical pre-stressed concrete invert siphon with multi-curve strands according to Chinese specification. The testing procedure is given and a formula is derived to calculate the frictional lose for the multi-curve strands. Then a simplified method is advised to evaluate the friction coefficient and wobble factor. The results show that the theoretical values recommended in the code fit with the testing deductive values and prove that the given values of friction lose for the design are reasonable as well. The conclusions would serve as a reference for similar engineering structures.

• Periodical: Applied Mechanics and Materials (Volumes 193-194)
• Pages: 822-825
• DOI: https://doi.org/10.4028/www.scientific.net/AMM.193-194.822
• Online since: August 2012
• Authors: Xiao Ke Li, Shun Bo Zhao, Long Jiang, Zhi Yuan Hu
• Keywords: Friction Coefficient (FC), Frictional Lose, Invert Siphon, Multi-Curve, Pre-Stressed Concrete, Wobble Factor

References

[1] Miao Peng, Tianqing Yu. Test of Friction Loss for Curved Prestressed Tendons, in: 2010 International Conference on Mechanic Automation and Control Engineering, June 26-28, 2010, Wuhan, China, pp.1490-1492.

DOI: 10.1109/mace.2010.5536083

[2] SL191-2008: Design Code for Hydraulic Concrete Structure (China Water Power Press, Beijing 2008).

[3] Shunbo Zhao, Xiaoke Li and Zhengrui Yan etc.: Techniques and Engineering Applications of Annular High-performance Prestressed Concrete (Science Press, Beijing 2008).