Strength Model And Application Of Upward Stratified Filling Body

With the augmentation of the social consciousness of environmental protection and safety, the developing mode of mining industry is changing so much, green mining is imperative. Filling mining method is an important way toward green mining, upward cut&fill is one of the most important methods, which is widely used at home and abroad, and is more and more applied seriously. In order to reduce the filling cost, upward cut&fill enerally use cemented fillings in the upper filled body, as upward mining work platform; The rest use the low-cost tailing filling. The main purpose of backfilled body is to provide the upward mining work platform.With the large-scale developing and increasing application of underground trackless equipments, the backfilled body strength design is more difficult. Traditional methods are for high-section filling body, can’t be used for upward layer filled body. At present a few design methods can be used to filled body strength, namely Terzaghi-Peck method and Tikov method, however, their strength values are large, which will raise the filling cost. And nether of them considered the thickness of cement layer.Therefore, the research on the panel mechanized to upward cut and fill method cement layer thickness and strength model has important theoretical meaning and engineering value.This article through studing the upper horizontal layered filling body at the bottom of the cement layer and the backfilling of the filling body stress condition and mechanism of backfilling materials that tailling filled body only need to bear of surrounding rock and overlying pressure, while the upper cementation layer to trackless equipment under dynamic load, dynamic load and filling body interaction mechanism is complex, studies have shown that large tensile stress at the bottom of the cementation layer upon layer cracking destruction, the most likely to lead to filling body cementation layer thickness, the greater the layer at the bottom of the smaller tensile stress.Through mechanism and stress analysis of filling body under trackless equipment dynamic loading. in reference to the design principle in roadbed engineering of roadbed, selecting the half sine pulse load, mine trackless equipment dynamic load fluctuation model is established. F=P+0.125Pmω2sin(ωt)×10-3 Using elastic mechanics method to calculate pack deflection value, compressive strength and shear strength of the expression under the action of vertical load and horizontal load respectively of trackless equipment, and synthesis, the calculation method of the components in the composite load, the cemented filling body strength models is established under the trackless equipment dynamic load, and the thickness design method is summed up for the first time.The thickness of cement layer should satisfy that:The compressive strength model of cement layer:The shear strength model of the cement layer:According to the filling body parameters of the west ore block of Dahongshan copper mine, using the above model to calculate reasonable cement layer thickness, compressive strength and shear strength under the action of part types of the Atlas scrapers, using the RFPA2D numerical analysis software simulate the calculation results, and it proves the model to be reasonable and reliable. Comparative and analyze the results with Terzaghi-Peck and Tikov method, the two methods’ results are significantly larger, it shows that the model is more economic and reasonable.Dahongshan copper mine west ore block point pillar to slice stoping method of stope engineering practice has proved that according to the model built in this paper, strength and thickness, it is concluded that the strength and thickness of the values, backfilling filling ratio design and two layered application, the results showed that after days the trackless equipment can normally operat on the filling body, and the backfilled body has no obvious phenomenon of fracturing damage and digging holes, the engineering application effect is very good, practice shows that this model is scientific.They can provide the reference for mines layered filling body design in the future.