Research On The Post-construction Settlement Characteristics Of Embankment Of Internal Waste Dump And Parameters Optimization Of The Overlying River

The hazards control, such as landslide of dumps and mud slides, is related to the mining safety life and property safety for people. The background of the paper is the river realignment in the coal inner dump of yuanbaoshan mine in chifeng. Combining in-situ research, laboratory tests, field monitor, analytical method and numerical method, settlements of the fill material and the stability of the slope were analyzed to support the river realignment in mining engineering in theory. The research has a significant influence on the safety of the river realignment in mining engineering. The main conclusions and achievement are as follows:On the basis of the research of rheology tests for sand gravel, an experiential creep model was presented and this model was suitable for the sand gravel. The stress-strain relationship of this model was presented by the exponential function. The strain-time relationship of this model was presented by hyperbolic function; compared with the laboratory tests, this model described the creep process of sand gravel under the different stress level and the fitting extent were high. This model was established by using the data of laboratory tests with the stress level 0.2?0.4? 0.6?0.8 and the results with the stress level 0.3?0.5?0.7 were predicted by this model. Comparing the predicted results and laboratory tests, the fitting extent was high and the predicted results had a good agreement with the laboratory tests. Based on the secondary development of the model in FLAC^3D and simulated the loading process, the numerical simulation and laboratory tests indicated that the fitting extent of these two curves was high, which verified the reliability of the FLAC^3D and provided the foundation to the FLAC^3D creep engineering.Based on the creep characteristic of the dump and the Burgers model, the dump was researched by using stratified summation method. During the dumping, the settlement of the bottom layer occurred under the variable load of the upper layer gravity. Therefore, it is necessary to establish a burgers creep model which is suitable for the settlement of dump. Coefficient of viscosity in this model was modified and nonlinear coefficient of viscosity was introduced to describe the whole process of the dump. This model calculated the settlements during the dumping, the settlements after the dumping and the total settlements in the analytical view. On the basis of the monitoring data of dump in qidashan iron mining, global search was applied by using simulated annealing-particle swarm algorithm, simulated annealing algorithm, particle swarm algorithm and nonlinear least square method. The results indicated that simulated annealing-particle swarm algorithm was a suitable method with less error and high fitting extent.Based on the data of monitoring for western dump in the inner dump of yuanbaoshan, the inversion of creep parameters was applied to acquire the parameters of the consistent Burgers model. The numerical simulation of the dumping was researched by using FLAC^3D for fine grained soil sand ?Burgers model? and gravel soil ?the developed sand-gravel model?. The settlements of the monitoring points were analyzed for the different extent of dumping. Combining the analysis of the location of the river, and the empirical settlement function with the numerical results of the monitoring points, the relationship between the maximum position of the river in the top platform of the inner dump and the dumping time was obtained. The results indicated that the distance between the selected position of the river and the original point was less than or equal to 136.8 m for the 2 years dumping. The final dumping position was 310 m.After the determination of the dumping position and region of the river, the regulation of the stability safety of the slope and the seepage characteristics of the dump were researched under the continuous heavy rainfall and short time heavy rain on the basis of the saturated-unsaturated seepage and analytical method of stability of the slope. The results indicated that the safety of the slope decreased with the continuous rainfall. It can be obtained that drainage cushion had an important influence on the stability of the slope. With drainage cushion in the inner dump, the initial safety of the slope was 1.347. However, this safety was larger than 1.3 under the continuous heavy rainfall and short time heavy rain, which satisfied the standard. Without drainage cushion in the inner dump, the initial safety of the slope was 0.901, which did not reach the standard. Based on the analysis on thickness of the drainage cushion, when the thickness of the drainage cushion was larger than or equal to 3 m, the thickness of the drainage cushion had a small influence on the initial water level safety of the slope was larger than 1.3 and reached the standard.In view of the above problems of the river realignment in yuanbaoshan dump engineering, the innovative achievements were as follows:?1? Based on the burgers model and the dumping process, creep model of settlements during and after the dumping was established. ?2? The method aimed at the selection of the position of the river in the inner dump was built and broke through the examples that built the rivers in the inner dumps. ?3? On the basis of the saturated-unsaturated seepage and analytical method of stability of the slope, the traditional limited equilibrium method was modified to analyze the stability of the slope of the inner dump under the continuous heavy rainfall and short time heavy rain and researched the regulation of the effects of rainfall infiltration on the stability of the slope in the inner dump.