地铁工程换乘通道高压旋喷桩试桩技术

摘要

Pick to:Due to this project with the existing subway member transfer, and geological buried depth of borehole is high, the intensity is high, in the form of enclosure structure design can only adopt the construction process of small oscillation, so the transfer channel for retaining structure design of rotary digging drill pile+dual pipe jet grouting pile and stop water heavy curtain to ensure that rotary spray pile water stop curtain to meet the design requirements, the water sealing results more attention should be paid to security risks, the pressure of high pressure spray on both subway station through the change to the high pressure jet grouting pile channel test pile construction technique through the scene test to determine the size of water cement ratio, speed of rotary spray pipe, mud pump pumping pressure, air compressor, gas pressure, the maximum dosage of cement, etc. Craft parameter, ensure that transfer channel of jet grouting pile construction smoothly.%由于本工程与既有的地铁员进行换乘，且地质岩面埋深高，强度高，在围护结构设计形式只能采用振动性小的施工工艺，因此换乘通道的围护结构设计为旋挖钻桩+高压双管旋喷桩止水帷幕，为确保旋喷桩止水帷幕的止水效果达到设计要求，更要注意高压喷浆对既有地铁站的压迫安全风险，现通过本次换乘通道高压旋喷桩试桩施工技术通过现场工艺试验确定浆液的水灰比、旋喷钻杆的提升速度、泥浆泵的送浆压力、空压机的送气压力、水泥的最大用量等工艺性参数，确保换乘通道旋喷桩施工的顺利进行。