智能等值张拉系统在基坑锚索施工中的应用

Application of Intelligent Equivalent Tensioning System in Foundation Pit Anchor Cable Construction

预应力锚索作为基坑、边坡支护的核心元件,对支护工程在服役期间的安全性、稳定性尤为重要,而基坑锚索的预应力损失在实际施工中主要受张拉方式、锚具锁定过程及后期基坑开挖等因素影响较大。运用新型智能等值张拉系统,依托鄂州航空都市区基坑支护工程对锚索进行现场试验,通过采用新型张拉系统与传统设备张拉过程对比,分析表明:采用新型张拉设备可以快速、高效地对锚索进行单根等值张拉,并能以稳定张拉力进行锚具锚固,从而有效减少预应力损失;新型张拉设备通过对锚索进行多次循环加载后锚固,可降低锚索锚固后受开挖影响产生的塑性变形,避免锚索预应力损失。该智能设备及张拉方法可为相关基坑预应力锚索施工提供有益借鉴。

As the core element of foundation pit and slope support, the prestressed anchor cable is particularly important for the safety and stability of the support project during its service period. However, the prestress loss of foundation pit anchor cable in actual construction is mainly affected by the factors such as tensioning mode, anchor locking process and later foundation pit excavation. By using a new intelligent equivalent tensioning system and relying on the foundation pit support project in Ezhou Aeronautical Metropolitan Area, the field test of the anchor cable is carried out. By comparing the tensioning process of the new tensioning system with that of the traditional equipment, the analysis shows that the new tensioning equipment can rapidly and efficiently perform the equivalent tensioning of a single anchor cable, and can anchor the anchor with a stable tensioning force, thus effectively reducing the prestress loss;the new tensioning equipment can reduce the plastic deformation caused by excavation after the anchor cable is anchored and avoid the loss of prestress of the anchor cable by repeatedly loading the anchor cable. The intelligent equipment and tensioning method can provide a useful reference for the construction of prestressed anchor cables in relevant foundation pits.