超量塌陷区铁路桥结构的检测与评估

为确定一期加固处理后的淮南超量塌陷区某铁路桥现阶段的结构性能,采用超声-回弹综合法、钻芯法、钻孔检测法、超声法等分别检测了该桥体的相关结构参数。结果表明,该桥一期加固混凝土强度小于35MPa,未达到设计要求;混凝土碳化深度小于0.5 mm,可忽略混凝土碳化引起的钢筋锈蚀及其对回弹测量的影响;钢筋直径、间距和混凝土保护层厚度,基本满足设计要求;4号孔3个箱体内的超声波速和波幅变化较小,顶板混凝土内部没有明显缺陷。该桥可正常运行。

Structural inspection and evaluation of railway bridge in over-subsidence area

The determination of the structure performance after the first treatment of Huainan railway bridge in over-subsidence area involves the detection of the structure parameters of the bridge by the use of supersonic rebound method,core drilling method,borehole testing method and supersonic rebound method.The results show that the bridge reveals the concrete strength of less than 35 MPa after the first treatment,hence failure to meet the design requirements;the carbonation depth of less than 0.5 mm allows the rebound testing changes from steel bar corrosion impact to be neglected; the parameter of steel bar diameter, spacing and concrete protection thickness-50 mm are basically up to the design requirements ; and there occure a smaller change in ultrasonic velocity and amplitude from three boxes of the 4th hole and there exists no obvious the internal concrete defect of roof. It follows that the bridge is in normal operation.