表观病害对预应力混凝土T梁桥承载力的影响分析

Analysis on the influence of apparent damage on the bearing capacity of prestressed concrete T-beam bridge

为研究表观质量缺陷对预应力混凝土T梁桥结构的承载力影响,详细调查了某T梁桥的质量病害及诱因,并通过静载试验测试了质量缺陷对结构承载力的影响程度。试验结果表明:在最不利工况下,结构控制截面处的应变、挠度校验系数值分别在0.62~0.89、0.71~0.89之间,均满足《公路桥梁荷载试验规程》承载力评定技术的要求;并分别从设计、原材料、模板、浇筑工艺以及拆模养护等方面提出了防治质量技术要点。

To study the influence of apparent quality flaw on the bearing capacity of prestressed concrete T-beam bridge,the quality disease and inducement of a T-beam bridge are investigated in detail,and the influence of quality flaw on the bearing capacity of the structure is tested by static load test. The results show that the strains and deflections of structure calibration values at the control section are in the range of 0.62~0.89 and 0.71~0.89 under the most unfavorable conditions,meeting the technical requirements for bearing capacity assessment in the Load Testing of Highway Bridges. In addition,the technical points of prevention and control have been proposed from such aspects as design,raw materials,formwork,pouring process,form stripping and maintenance,etc.