Bearing capacity assessment method for PC box girderby testing stress of tendon(PDF)
长安大学学报（自然科学版）[ISSN:1006-6977/CN:61-1281/TN]
- Issue:
- 2019年01期
- Page:
- 61-69
- Research Field:
- 桥梁与隧道工程
- Publishing date:
Info
- Title:
- Bearing capacity assessment method for PC box girderby testing stress of tendon
- Author(s):
- ZHAO Yu; HONG Lujia; ZHOU Yongjun
- (Key Laboratory of Bridge Detection Reinforcement Technology of Ministry of Communication,Changan University, Xian 710064, Shaanxi, China)
- Keywords:
- bridge engineering; prestressed concrete boxgirder; effective stress of tendon; prediction; crosssection analysis; safety assessment
- PACS:
- -
- DOI:
- -
- Abstract:
- In order to perform quantitative assessment on the safety performance of PC boxgirder bridges with cracks during service period, the evaluation method for the bearing capacity of a damaged PC boxgirder bridge was carried, based on the partial effective stress test of a tendon in a PC boxgirder bridge. Firstly, based on the principle of parameter identification and the correction method, the variation in transient prestress loss, including frictional loss and antifriction loss, was represented by the friction loss parameters, and a new method was proposed to predict the effective stress on the inner tendons from the outer tendon. Then, an equilibrium iteration algorithm and a procedure for considering the tensile strength of concrete in the cross section were developed. Finally, a fullscale experiment was carried out for three girders . The stress on the outer tendon at the midspan section of the girders was measured using a special stress detector. Using the proposed method, the stress of the inner tendon at the midspan section was predicted. The measured load, deformation, and the failure mode of the structure during the entire loading process was obtained. A comparison was made between the theoretical results proposed in this paper and the experimental results. The results show that calculated strain of the test girders is in good agreement with the experimental results, which illustrate that the stress prediction method of the tendon and equilibrium iteration method can accurately reflect the mechanical characteristics of a damaged PC box girder. It can be used to quantitatively evaluate the bearing capacity of boxgirder bridges with damage during service period. 3 tabs, 9 figs, 22 refs.
Last Update: 2019-01-28