|
Abstract Based on the study of time functions during dynamic analysis of mining subsidence both at home and abroad，the probability integral method is used to study the regularity that surface subsidence caused by underground mining varies with the changes of time and space；and the coordinate-time functions of dynamic surface movement and deformation are proposed. Compared to Knothe time function W(t)，the coordinate-time functions not only add a coordinate variable x，but also add several strata movement parameters(q，r，v，ω，?，t0) which are unified with the parameters used in static analysis of probability integral method. Relation formula of starting time t0 changing with coordinate variable x is studied. Compared to some typical time functions such as Knothe time function，subsidence coordinate-time function W(x，t) can overcome the imperfections of first derivative and second derivative that exist in Knothe time function. What?s more，the changing regularities of subsidence，subsidence rate，subsidence acceleration are correctly revealed. Besides，coordinate-time functions of dynamic tilt，dynamic curvature，horizontal movement，horizontal deformation，etc.. can be obtained from partial derivative calculation of x . Then，basic formulae of dynamic analysis of surface movement and deformation are established under conditions of semi-infinite mining and finite mining. Based on the above topic and analysis，practical verification combined with examples is accomplished. The results show that the conventional static analysis function is just a special case of the coordinate-time functions of surface movement and deformation；and the coordinate-time functions correctly describe the dynamic process of surface subsidence. The coordinate-time functions including several well-known strata movement parameters could fully reflect geological mining conditions and it deserves to be spread widely.
|
|
Received: 23 March 2011
|
|
|
|
2011, Vol. 30 
