青岛胶州湾海底隧道涌水断层注浆效果综合检验方法研究

STDUY OF COMPREHENSIVE TEST METHOD FOR GROUTING EFFECT OF WATER FILLING FAULT IN QINGDAO KIAOCHOW BAY SUBSEA TUNNEL

采用注浆全过程注浆压力–注浆量–注浆时间(P-Q-t)控制法、物探法、检查孔法与数字钻孔摄像法从宏观到细观对青岛胶州湾海底隧道F4–4涌水断层全断面帷幕注浆后的注浆效果进行检验,其中注浆全过程压力–流量–时间控制法将注浆压力限制在3～4 MPa,当注浆速度小于5 L/min超过20 min时,结束该孔注浆;TSP物探法对注浆前后的含水断层探测结果表明,注浆后围岩整体性得到提高,其变形模量提高19.1%,密度提高3.6%,泊松比下降7.1%,纵波波速VP增长0.8%,纵横波比VP/VS减小7.1%;按注浆孔的5%～10%钻探检查孔,当单孔出水量≤0.15 L/min时,达到注浆要求,满足开挖允许出水量标准;数字钻孔摄像法生成三维虚拟岩芯,计算裂隙充填浆脉的充填隙宽及产状,表明注浆后裂隙充填密实。4种检验方法综合判定含水断层注浆后围岩等级由V级提高到IV级,表明注浆效果良好,达到注浆止水加固的目的,综合检验法是检验注浆效果的有效方法,上述方法对类似工程具有一定的借鉴与指导意义。

Grouting pressure-grouting flow-grouting time（P-Q-t） control method in grouting entire process,geophysical method,check drilling method and digital camera method from macro to micro had been applied in testing in grouting effect of water filling fault F4-4 in Qingdao Kiaochow Bay subsea tunnel.P-Q-t control method in grouting entire process in which the entire process of grouting P-Q-t control act,grouting pressure in order to limit within 3-4 MPa,when the speed is less than 5 L/min grouting over 20 min,the grouting was ended;the TSP is used to check the surrounding rock after grouting.The results indicate that the integrity of surrounding rock has improved;and its deformation modulus has improved 19.1%;and its density has improved 3.6%;and its Poisson s ratio has reduced 7.1%;and the VP has improved 0.8%;and the ratio of longitudinal wave velocity of transverse wave velocity VP/VS has reduced 7.1%.The drilling inspection holes amount was 5%-10% of grouting holes.When the single-hole out of water was less than 0.15 L/min,it reached grouting requirements,then it meets the excavation allowed out of water standard.The digital camera method generated three-dimensional virtual cores,then calculated the fracture gap filling paste filling pulse width and the occurrence.It is indicated that the water-filled fissure filling compact.All of above four kinds of test methods determined that the surrounding rock level of water filling fault after grouting has improved from grade V to grade IV.The results show that the grouting effect is good;and it achieved the purpose of reinforcement of the grouting sealing.The comprehensive check method is an effective method of grouting.The above method has some referential and guidance significance to similar projects.