The other day，Erqi Road River-crossing Passage Invested and Constructed by Wuhan City Investment Group Company（Jiefang Avenue—Yanjiang Avenue Section）The project successfully completed the concrete pouring of the bottom slab of the station section，The open-cut section has fully entered the construction stage of deep foundation pit floor，Verified again the use of double bottomCSMConstruction method（Milling deep mixing cement-soil mixing wall）+Foundation pit supporting form of underground continuous wall，And that construction of the ultra-deep foundation pit in the high artesian wat area is more efficient.、Reliable supporting scheme for foundation pit。

Project feature 1

Foundation pit excavation of shield working shaft 47.7 meters The water head difference inside and outside the foundation pit is up to 40 meters.

The Erqi Road River-crossing Passage is located between the Second Wuhan Yangtze River Bridge and the Erqi Yangtze River Bridge.，It is the first double-deck two-way six-lane shield tunnel on the Yangtze River.，Shield OD up to 15.5 meters，It is the largest shield tunnel under construction in China.，The shield end shaft area is only 70 meters away from the Yangtze River embankmentm，And the super-large diameter shield needs to cross the Yangtze River.，The design excavation depth of the end well area is 47.7m，The deepest point is equivalent to the height of a 16-story building excavated downward.。

The ultra-deep excavation depth makes the inside and outside of the foundation pit form nearly 40mThe water head is poor，Faced with such a complex working condition，Any carelessness in construction will cause incalculable losses.。

Project zoning depth map

Project feature II

CSM+Diaphragm wall double insurance foundation pit anti-seepage is foolproof

Integral reinforcement of shield end shaft areaCSMDeep mixing and reinforcement of cement-soil of equal thickn，The overall foundation pit is supported by double bottomCSM+Diaphragm wall。The Yangtze River in WuhanⅠTerrace，The foundation pit is close to the Yangtze River levee，Surrounding structures are extremely sensitive，Ultra-high confined water condition， All “Low probability，High risk”Problems should be resolutely avoided.。

Pile formation shall be based on actual conditions（The wall）Quality requirements，After several demonstrations, the original design was finally determined.MJSThe joint water stop of the diaphragm wall is adjusted to be continuously closed.CSMDrop to the bottom to stop water，Ensure the safety of foundation pit to the greatest extent！

Project Feature III

CSMConstruction method, equipment, low noise and micro-disturbance to ensure peripheral safety

Because the project is adjacent to Binjiangyuan Community, most of the piles are about 18mRammed expanded pile foundation，AdoptCSMThe construction method is also to minimize the impact of construction on the surrounding environment.。CSMThe construction method is low air pressure、In-situ forced mixing under low slurry pressure，The power system is an electro-hydraulic configuration，Can be adopted during construction“Hit one and jump three.”Construction method，Reduce the impact on the surrounding environment to a greater extent，It is a veritable low-noise micro-disturbance foundation construction equipment.。

Project feature IV

Core pulling sampling rate up to 95%The above core-pulling pass rate is 100%

To ensure the safety of foundation pit，Strict inspection has been carried out for each process.，YesCSMRandom sampling of hundreds of walls，The core pulling sampling rate is 95%Above，Core strength 1.0-3.0Mpa，Core-pulling percent of pass 100%，Foundation pit connectivity test，Total water yield of foundation pit 36m³/h，High-quality Seepage Impermeable Curtain Escorts Construction of Foundation Pit。

CSMIntroduction video of construction method

Shanghai Jintai has been the first since 2011.CSMConstruction equipment has been used for 12 years since it came out.。In these 12 years,，Continuous innovation and improvement of products，Continuous improvement and upgrading of functions。Kim TaeCSMConstruction method equipment occupies the absolute leading position in China in terms of product spectrum and application results.。

Zhengyu Kechuang（Wuhan）Geotechnical Engineering Co., Ltd. is one of the few professional companies focusing on the construction and promotion of ultra-deep cement-soil mixing wall in China.，Strong alliance with Shanghai Jintai Construction Machinery Co., Ltd.，Contribute to the new development of Wuhan。

AtCSMContinuous deep ploughing in the research and promotion of construction methods，Continuous development，Cross the river at Erqi Road（Jiefang Avenue—Yanjiang Avenue Section）Rebuild new achievements in the project，Climb the peak！