PRESTRESSING FORCE DETECTION BY DYNAMIC METHOD
The prestressed tendon is the key part of prestressed concrete beam, so knowing the existing prestressing force and the prestressing loss is the key to estimate the health of PSC beam.Dynamic detection of prestressing force is simple and easy, but the relationship between the dynamic characters and prestressing force must be found out. Dynamic test of an un-bonded and three bonded full-prestressed concrete beams were carried out, the test results indicate that frequencies of PSC (prestressed concrete) beam grow in step with prestressing force, though the increasing rates of the frequencies are not the same. Its opposite to the analysis of classical isotropic material beam which was subjected to axial compressive force. The available equations are more of theoretical nature, and they cannot explain this observed response. Existing modified models have such-and-such limitation.The fundamental reason is found that dynamic elastic modulus is altered by the prestressing force.Hereby, calculation model is modified according to the test measured frequencies. The calculated result of first mode frequencies accord to the measured result well, the calculated result of second mode frequencies have some errors to measure results.
Full-prestressed concrete beam Prestressing force Nature frequency Experiment Modified model
Rui-Ge Li Yao-Ting Zhang
School of Civil Engineering & Mechanics, Huazhong University of Science and Technology,Wuhan 430074, School of Civil Engineering & Mechanics, Huazhong University of Science and Technology,Wuhan 430074,
国际会议
第十届国际结构工程青年学者研讨会(The Tenth International Symposium on Structural Engineering for Young Experts)
长沙
英文
1483-1488
2008-10-19（万方平台首次上网日期，不代表论文的发表时间）