采用玻璃纤维复合筋(GFRP Bar)材代替钢筋能够有效解决传统钢筋混凝土桥面结构由于钢筋锈蚀所引起的结构功能退化问题。过去试验研究表明在FRP筋混凝土桥面承受集中荷载作用下,冲切破坏模式是一种常见的破坏模式。本次研究采用现有规范及已经发表抗冲切承载力计算模型对多组混凝土桥面板试验结果进行冲切承载力预测。通过与试验结果对比发现,由于大多数理论模型是基于简支构件试验结果建立的经验公式,其无法准确计算FRP筋混凝土桥面结构的冲切承载力。笔者前期建立的GFRP筋混凝土桥面板承载力理论方法考虑了拱效应的作用,计算结果与试验结果有较好的吻合。理论分析中发现,由于较高配筋率和较小跨高比,大部分GFRP筋混凝土桥面板发生剪切破坏而非弯切破坏。因此本文建立了简化的GFRP筋混凝土板剪切承载力计算方法,该模型计算结果与多个试验结果吻合良好。
The structural degeneration problems of reinforced concrete bridge deck slabs due to the corrosion of steel reinforcement can be solved by the replacement reinforcing material such as glass fiber polymer reinforcement( GFRP). In the previous research of concrete deck slabs,it was found that punching failure was the common failure mode. In this study,several theoretical models,such as current design codes and methods in literatures,were used to predict the ultimate strengths in the test results of GFRP reinforced concrete deck slabs. In the comparison of prediction results with the test results,it was found that most of theoretical models could not predict the punching capacity accurately,which the empirical equations were based on the experimental tests of simply supported structures.A theoretical method with consideration of arching action previously proposed by authors showed good coloration with the punching capacities from the tests. In the analytical study,it was shown that high reinforcement percentage and small span-to-depth ratio resulted in shear punching failure but not flexural punching failure in GFRP reinforced concrete bridge deck slabs. Therefore,a simplified theoretical method was proposed in this paper. The prediction results from this method showed good agreement with the test results.