高速公路大跨径盖梁主动托换关键技术与效果评价

Evaluation on the Key Techniques and Effect of Active Underpinning for Large Spanning Capping Beam of Highway

为了解决新建路线下穿既有结构,保证大跨径盖梁托换后满足规范要求,对大跨径盖梁托换过程的关键技术和施工监控数据进行分析研究。以广河高速82号墩为依托,采用MIDAS Civil建立有限元模型,验算了新建盖梁的挠度和应力,并分析了新旧盖梁前10阶自振频率,结合施工监控数据对盖梁托换后的效果进行评价。结果表明,新建盖梁托换旧盖梁后,施工监测的结果均小于计算理论值,监测的结果较平稳。盖梁托换后顺桥向的刚度比旧盖梁提高了16.61%,横桥向的刚度比旧盖梁降低了23.09%。

To solve the problem that a new route can cross the existing structure,and the large-span capping beam are satisfied with the code after underpinning,the key technology and construction monitoring data of the underpinning process are analyzed and studied.The No.82 Pier of Guanghe Highway is taken as the background,software Midas Civil is used to establish a finite element model to analyze its deflection and stress.Meanwhile,the first 10 order natural frequencies are compared between the old and new capping beam.Combined with construction monitoring data,the effect of capping beam replacement is evaluated.The results demonstrate that the data of construction monitoring are less than the calculated theoretical values after underpinning,and the long-term monitoring results are more stable.The stiffness along the bridge is 16.61%higher than that of the old capping beam after underpinning,and the stiffness in the transverse direction is 23.09%lower than that of the old capping beam.