摘要
研究目的:为解决超深富水卵石地层的止水加固难题,在北京某在建工程基坑中的富水密实卵石地层中开展超高压旋喷注浆法加固现场试验,由地面垂直实施数组咬合或单一的超高压旋喷试验桩,在基坑开挖过程中对超高压旋喷试验桩的成桩直径、桩体强度、桩间咬合、咬合体强度及渗透系数进行现场测量和试验测定。研究结论:(1)超高压旋喷注浆法在超深富水密实卵石地层中能形成1.5 m以上直径的加固桩体,试验最大直径2.6 m;(2)超高压旋喷桩间能形成完整咬合体,旋喷桩及桩间咬合体平均强度达10 MPa以上,渗透系数达10-8cm/s级别,能实现卵石地层的加固或注浆止水;(3)超高压旋喷注浆技术在超深富水卵砾石地层中是适用的,技术可行,可以作为超深富水卵砾石地层加固和注浆止水的辅助工法加以推广应用。
Research purposes ： To solve the problem of water sealing and strengthening in ultra - deep and water - rich gravel stratum, the field test was carried out with the super high pressure jet grouting method, several sets of lock - joint or single high pressure jet grouting piles were constructed in the foundation pit which was under construction in Beijing, the diameter, strength and hydraulic conductivity of test piles and overlaps were measured in situ and by the experiments during the excavation of the foundation pit. Research conclusions： （ 1 ） Large diameter piles can be formed by super high pressure jet grouting in ultra - deep and water - rich dense gravel stratum, the diameter of which can be larger than 1. 5 m, the largest diameter in the experiment is 2.6 m. （2） Overlap between super high pressure jet grouting piles can be formed in ultra - deep and water - rich gravel stratum, of which the mean strength is over 10 MPa and hydraulic conductivity can reach to the level of 10-8 cm/s, which can fully meet the requirements of reinforcement or water sealing. （3） Super high pressure jet grouting technology is feasible in technique and suitable for ultra - deep and water - rich gravel stratum, the method can be used as an auxiliary method for reinforcement and water sealing in similar stratum.
出处
《铁道工程学报》
EI
北大核心
2017年第12期13-17,共5页
Journal of Railway Engineering Society
关键词
超高压旋喷注浆
卵砾石地层
注浆加固
试验研究
super high pressure jet grouting
gravel stratum
grouting reinforcement
experimental study
