|
|
|
| New progress in grouting reinforcement theory of water-rich soft stratum in underground engineering |
| ZHANG Qingsong1, ZHANG Lianzhen1,2, LI Peng1,3, FENG Xiao1
|
New progress in grouting reinforcement theory of water-richsoft stratum in underground engineeringZHANG Qingsong1, ZHANG Lianzhen1, 2, LI Peng1, 3, FENG Xiao1(1.Geotechnical and Structural Engineering Research Center, Shandong University, Jinan 250061, Shandong, China;
2.College of Pipeline and Civil Engineering, China University of Petroleum, Qingdao 266580, Shandong, China;
3. College of Engineering, Ocean University of China, Qingdao 266071, Shandong, China |
|
|
|
|
Abstract At present, China is the country with the greatest scale and difficulty in the construction of tunnels and underground projects. Fault fracture zone, water-rich sand strata and other water-rich soft strata have become the most common unfavorable geologic bodies in the construction of underground engineering. Grouting is the main method to treat water-rich soft strata. Based on the characteristics of the project team, the latest research progress in grouting reinforcement theory, simulation test and grouting control method in water-rich soft strata was introduced. In terms of grouting reinforcement theory, considering the layered characteristics and space attenuation characteristics of reinforced soil, a quantitative method for calculating the reinforcement effect of splitting grouting was established by synthesizing the performance parameters and spatial distribution of grouting veins, compacted strata and undisturbed strata. What's more, considering the inhomogeneity of the retention space of cement particles caused by filtration effect in sand layer, a quantitative strength calculation method of grouting reinforced composition ground was established for the permeation grouting form of plane radial flow. On this basis, the spatial attenuation characteristics of grouting strength were revealed. In the aspect of simulation test of grouting reinforcement, a simulation test system for grouting after water inrush and mud inrush of tunnel was developed. The rule of priority filling and diffusion in cavities and soft broken areas and the law of multi-sequence split grouting diffusion in closed space strengthened area were summarized. A visual simulation test system for splitting grouting was developed, which could reveal the variation rule of split channel shape with time during grouting. The influence range of splitting and compaction grouting under test conditions was obtained. In terms of grouting control methods, the corresponding grouting control methods for muddy fault fracture zone and water-rich sand layer were put forward respectively, which could provide effective guidance for grouting engineering practice in water-rich weak stratum.
|
|
Received: 24 May 2018
Published: 22 February 2019
|
|
|
|
|
|
|
|
