盾构隧道的结构病害及其成因探析和治理措施

随着大量盾构隧道投入运营,隧道结构的病害问题逐渐显现。本文从影响和引起隧道结构病害的原因出发,对盾构隧道服役寿命期内其结构病害的情况进行了总结,阐述了盾构隧道结构病害、劣化的主要类型及其内在和外在的表征形式。事实显示,引起盾构隧道结构病害的主要成因包括:运营期特殊荷载导致的隧道结构突发损伤、隧道结构耐久性不足和隧道结构变形等长期行为产生的损伤。盾构隧道结构的病害和损伤主要包括管片和路面结构混凝土开裂、破损剥落;钢筋锈蚀且与混凝土粘结力降低;管片连接螺栓锈蚀或长期受应力腐蚀作用产生扭曲变形甚至断裂;隧道衬砌环纵缝的错台变形、接缝张开等;另外还包括隧道管片、衬砌接头、螺栓孔等位置的渗漏。

Structure Damage and Its Cause Analysis and Protecting Measures of Shield Tunnel

With a large number of shield tunnels are put into operation,the tunnel structure damage problem appears gradually.In this paper,the structure damage of shield tunnels during its service life are summarized based on the analysis on factors that influence and cause the damage.The main forms of existing shield tunnel damage or degradation are stated,as well as the inherent and exterior characterization in the form.The fact indicated that the main reasons which induced existing shield tunnel damage are as follows：shield tunnel sudden damage induced by special load in operation period,damages because of the lack of structure durability and structural malformation.The shield tunnel structure damage or degradation includes：concrete cracking and spoiling of segment or pavement structures, steel corrosion and concrete adhesion stress reduction,distortion or fracture induced by segment connecting bolt rust or long-term stress corrosion,deformation of tunnel lining’s collar joint or juncture-open,in addition to the leakage at segment,lining joint and bolt hole.