Study On The Theory And Parameters Of Surface Subsidence Prediction Of The Overlying Strata And Bed-Separation Under Grouting

Method of reducing subsidence by grouting in bed-separations in overburden is a active one to control surface subsidence. By this time, the technology is advanced in theory and engineering. Many mines took the test of reducing subsidence by grouting in separations in China, and succeeded.The new scheme of equivalent materials simulation technique, simulation test of equivalent materials under constant temperature and humidity is proposed. The purpose is to analyze the law of the overlying strata displacement and the surface subsidence by model experiment of equivalent materials and to make the simulation results quantitative. On the base of Elastic Mechanics, theory of offset error is founded through analyzing the main origin of error and its amenability in the course of experiment.The dynamic displacement of overburden strata and surface is studied by adopting the method of numerical simulation, under the condition of idiographic geology. The process of the movement of surface with the face advanced is simulated factually.According to theory of key strata, the relation between overlying strata structure and bed-separations developing process is discussed. The stage property and period property of bed-separations development is also analyzed. The development law of strata fracture is analyzed in the cross direction by use of the equation for the deflection of strata beam. This depends on the strata' s property of anti-pressure and non-anti-tensibility. At the same time, this takes the strain as index. The expression of strata beam' s fracture distance between two steps is deduced based on its strain. The relation between development of bed-separations and width of face is also analyzed.The thesis combines to National Natural Science Foundation (NO. 50174035). The method of estimating the surface subsidence under grouting is studied. The effect of reducing subsidence is evaluated by the ratio of mining and grouting. The distribution of fine coal ash influences upon subsidence is analyzed. The...