Yunnan Tin Tong Sub-concave Loose Rock Grouting Reinforcement Pilot Study

With the highly development of technology on underground works and foundation engineering, more and more projects have proved that grouting in underground works and foundation engineering with complex engineering geology and hydrogeology is a new economical technology and can ensure security and quality. Application of grouting in many fields makes it get great development in every aspect, and lots of experiences are gotten from them. But till today, researches on grouting theory in loosen rock mass are not many. So, researching on grouting theory in loosen rock mass and its consolidated mechanism is of great significance.According to the characteristics of grouting in loosen rock mass, the author studied and deducted formula of different nature liquid under corresponding flow model to calculate distribution of flow velocity, quantity of flow and pressure drop. These formulas reflect the relationship between the grouting amount, grouting time, grouting pressure and grouting range, and also reveal movement and diffusion rules of grout in loosen rock mass, which can provide theoretical basis for design and construction work of grouting project in loosen rock mass.The author did commercial test on grouting in loosen rock mass based on Tangziwa grouting project in loosen rock mass. First, fixed the area of grouting consolidation used the theory of retaining wall, and used 3-D finite element program to simulate the stability of it. Then, designed reasonable grouting construction scheme combined with practical situation of the project. Also, studied key techniques about grouting in loosen rock mass, such as drilling technique, collaring sealing technique and so on. At last, built 3-D model of grouting consolidation, which can reflect clearly practical situation and effect of grouting strengthen. Appraise grouting effect combined with practical construction of the project, and the result indicate that the project can reach anticipated effect.Good strengthen effect in loosen rock mass has been gotten through the research methods of theoretical analysis-engineering example-theoretical analysis. Based on the project, further cognition of the regularity about grouting in loosen rock mass.