盾构软土地层微扰动正穿超高建筑物技术

Technology of Underpassing Buildings with Micro Perturbation by Shield in Soft Soil

当盾构隧道从建筑物正下方穿过时,盾构施工常会对上部建筑物产生较大影响,需采取有效措施减小影响。常州地铁1号线要穿越科教城的两所高校,校内建筑物较多,且沉降控制要求较高。从设计、施工两方面探讨盾构微扰动正穿建筑物的措施:控制推进速度、土压力、出土量、同步注浆、二次注浆等参数;采用有效的纠偏、盾尾防漏方法;进行土体改良;注意管片拼装细节,加强监测。实践证明,这些措施达到了预期目的。

When the shield tunnel passes underneath, the shield construction often has a great impact on the buildings above. Thus effective measures should be taken to reduce the impact. Changzhou Metro Line 1 is due to under-pass two universities in the Science and Education City where high-rising buildings are clus- tered, which puts heavy demands on the settlement control. The measures of passing beneath buildings with micro perturbation by shield are explored from the aspects of design and construction. The practice has proved that by controlling advance speed, soil pressure, the unearthed amount, synchronous grouting and secondary grouting, and by taking effective action such as error correction and shield tail leakproof, soil im- provement as well as paying attention to the details of the shield segment assemble and monitoring, the shield can safely pass beneath the high buildings.