基于TJS工法的盾构隧道运营变形控制

Deformation control of shield tunnel operation based on tunnel jet system method

开展隧道洞内全方位微扰动高压喷射注浆(TJS)工法对运营隧道变形控制的研究.基于典型区间运营隧道实测数据,采用Plaxis 3D有限元数值模拟软件分析TJS工法横断面布置中桩长、打设角度、桩径对隧道加固效果的影响,通过在隧道底部打设局部垫层的方法优化TJS工法.结果表明,桩长越长、角度越接近40°、桩径越大,对隧道沉降的控制效果越明显. TJS工法加固后的隧道地表沉降减少16.38 mm,水平收敛变形为未加固时的42.87%.局部垫层能够显著提升TJS桩的加固效果,“两侧短中间长”的布置能够兼顾加固效果和降低施工成本.

A study was carried out on the deformation control of operational tunnels using the tunnel jet system(TJS)method.Based on measured data from a typical operating tunnel section,a finite element numerical simulation software Plaxis 3D was used to analyze the influence of pile length,pile angle and pile diameter on the tunnel reinforcement effect in the cross-section arrangement of the TJS method.A method for optimizing the TJS method was proposed by placing a partial cushion layer at the bottom of the tunnel.Results showed that a longer pile length,an angle closer to 40 degrees,and a larger pile diameter led to a more pronounced ability to control tunnel settlement.The ground settlement of the tunnel reinforced by the TJS method was reduced by 16.38 mm,and the horizontal convergence deformation was 42.87%of that of the unreinforced tunnel.A partial cushion layer greatly enhanced the reinforcement effect of TJS piles,the layout of“short on both sides and long in the middle”reduced construction costs while taking into account the reinforcement effect.