内嵌光纤自感知钢绞线在预制管廊拼装中的应用

Application of Self-sensing Steel Strand with Built-in Optical Fiber in Assembly of Prefabricated Utility Tunnels

预制管廊拼装过程主要依靠预应力钢绞线张拉锁紧使管节拼装就位。在预制管廊拼装张拉过程中,各处张拉同步性是否良好,运廊车运行阶段是否造成接头张拉力松弛,都将直接影响管廊接头止水条接头的防水性能。为探究在管廊拼装过程中钢绞线的张拉同步性和预应力损失,采用内嵌光纤自感知钢绞线对管廊拼装的张拉过程进行实时监测,验证智能钢绞线对张拉监测的可行性,并分析评价了张拉过程的同步性能和预应力损失的程度。该方法可为长节段大吨位预制管廊拼装张拉工艺性能评估提供技术支撑。

The assembling process of prefabricated utility tunnels mainly depends on the tensioning and locking of prestressed steel strands to make pipe joints assembled in place. In the process of assembly and tensioning, whether the synchronization of tensioning is favorable and whether the joint tension is caused relaxed in the operation phase of the utility tunnel transport vehicle will produce a direct effect on the waterproof performance of the water stop joint of the utility tunnel joint. In order to explore the tensioning synchronization and prestress loss of steel strands in the process of utility tunnel assembly, the self-sensing steel strands with built-in optical fiber are used to conduct real-time monitoring of the tensioning process of utility tunnel assembly, verify the feasibility of intelligent steel strands used for tensioning monitoring, and analyze and evaluate the synchronization performance of the tensioning process and the degree of prestress loss. This method can provide technical support for the performance evaluation of the assembly and tensioning process of the long segment and large tonnage prefabricated utility tunnel.