Research On Roof-Contacted Filling Based On Expanding Material

Recently, geological disasters occurs frequently due to the exploitation of underground mineral resources where surface subsidence, ground collapse, rock blasting, rock caving and other disasters have become increasingly prominent, which has affected the socio-economic development seriously. Back-filling method using the filling body to manage ground Pressure, control rock avalanche and surface subsidence, it can alleviate many problems faced by underground mining. However, due to the inherent nature of the filling slurry, unclosed roofs phenomenon occurs frequently. This is a security risk to the normal production of mine.To solve the problem of unclosed roofs, this article analyzed the factors affecting unclosed roofs in-depth. Starting from the root causes unclosed roofs:bleeding and settlement of the slurry, low filter efficiency of the retaining walls. On the one hand, introduced the Expansion Material of aerated concrete in building to solve the problem of bleeding and settlement, making the slurry expands, to make the roof contact. On the other hand, summarize the advantages and disadvantages of existing retaining wall, on the basis of the existing retaining wall, Proposed a new type, to solve retaining wall's problem: Labor-intensive?low Filter rate and bad blocking effect. Main ceontents and main conclusions of this paper are summarized as follows:(1) Combined with the production of aerated concrete, choosing the right expansion material based on chemical reactions.(2) Take Hong toushan tailings as aggregate, ordinary 325# portland cement as cementitious material, Hydrogen peroxide as gas former to determine the concentration and the amount of blowing agent added, Select the appropriate concentration range of slurry and the appropriate amount of peroxide.(3) Make the test of expansion properties, bleeding properties, compressive strength of the Filling slurry, Studied the relationship between the amount of hydrogen peroxide and expansion, bleeding and compressive strength properties.(4) Summarized the factors which affect the expansion results of slurry during the experiment, Analyzed how pore structure affect the performance of filling body.(5) Summarized the advantages and disadvantages of present retaining wall proposed a combined retaining wall and tested its strength. Using the simulation software of ANSYS to imitate filling process to optimize the structure.