【作者】 王正帅；

【导师】 邓喀中；

【作者基本信息】 中国矿业大学 ， 大地测量学与测量工程， 2011， 博士

【摘要】 老采空区上方兴建建(构)筑物作为一项行之有效的采矿塌陷地利用措施,兼具增加建设用地、恢复地物景观、改善矿区生态环境等优点,在采矿塌陷地治理中有着广阔的应用前景。本文在收集、分析老采空区地表沉陷资料的基础上,采用非线性理论,系统研究了老采空区时空变形规律、预测方法及预测参数体系,构建了老采空区上方建筑地基稳定性评价模型,为老采空区上方建筑利用提供了必要的技术支持。主要成果如下:(1)提出了地表动态沉降的全过程预测模型,并将其与概率积分法相结合,建立了采动区地表任意点在任意时刻沿任意方向的移动变形预测模型。分析了老采空区残余沉降持续时间、残余沉降量与地质采矿条件之间的关系。研究表明,基岩厚度越大、工作面推进速度越小,则残余沉降量越大、残余沉降持续时间越长。(2)研究并建立了老采空区概率积分法动态参数体系。统计分析表明,采动程度越高,残余下沉系数和残余主要影响角正切越小;基岩采厚比越大,时间参数越小,下沉系数和主要影响角正切的变化过程越缓慢。(3)提出了概率积分法参数辨识的多尺度核偏最小二乘回归方法(multi-scale KPLS),为缺乏实测资料的矿区求取概率积分法参数提供了一种新的方法。建立了概率积分法修正模型,实例分析表明,该模型较好地解决了下沉曲线和水平移动曲线在边界附近收敛过快的问题。(4)开展了老采空区残余沉降时变特征的多尺度分析。分析表明,老采空区残余沉降具有明显的周期性,各变化周期表现出一定的阶段性;同一采空区中,不同测点有相等或近似相等的显著变化周期和持续时间。(5)针对老采空区残余沉降序列具有随机波动性的特点,建立了老采空区残余沉降预测的WT-SVM、GM-Markov和DGM(2,2)模型,分别适用于观测序列长度l≥20、10≤l<20和6≤l<10等情况下的残余沉降预测,其预测步长不宜超过l/5步、4步和2步。(6)提出了导水裂缝带高度预测的模糊支持向量机模型(FSVM),以导水裂缝带高度不能与建筑物荷载扰动深度相重叠进行荷载作用下的老采空区稳定性评价;建立了老采空区稳定性的模糊可拓评价模型。实例分析表明,上述两种评价方法与基于概率积分法修正模型的老采空区残余沉降预测相结合应用于老采空区稳定性评价是可行、有效的。该论文有图66幅,表47个,参考文献202篇。更多还原

【Abstract】 Building on the old goaf, an effective measure to reclaim subsidence land induced by mining, will be widely applied for treating the subsidence land ascribing for these advantages, such as increasing available construction ground, resuming the scenery of old goaf surface, improving the environment of the mining area, and so on. On the basis of collecting and analyzing the field data of surface subsidence and using non-linear theories, the law of spatio-temporal deformation, prediction methods and parameters system were studied systemically and the evaluation model of foundation stability of old goaf buildings was constructed, which would provide the indispensable technology support for construction utilization above the old goaf. The main results are as follows:(1) Integrated prediction model of surface dynamic subsidence was proposed in this dissertation, and combining with probability-integral method, another prediction model was presented to calculate the movement and deformation of arbitrary point in mining area in any direction and at any time. The relationship was analyzed between geological mining conditions and the duration time and value of residual subsidence. The results show that the duration and the value of residual subsidence increase with increasing the thickness of rock strata and decreasing the advance speed of the working face.(2) Dynamic parameters system of probability-integral method was established. Statistical analysis shows that residual subsidence coefficient and the main influential angle tangent decrease with increasing the mining degree, and the time parameter decreases with increasing the ratio of rock strata and mining thickness and the movement process of subsidence coefficient and the main influential angle tangent become slower.(3) A novel method named multi-scale kernel partial least-squares regression (multi-scale KPLS) was proposed to identify parameters of the probability-integral method in mining area lacking of filed data, at the same time, amended probability-integral method was put forward in this dissertation, which effectively solved the problems of quick convergence on the edge of subsidence and horizontal movement curves.(4) Multiple scales analysis on time variational character of old goaf residual subsidence was carried out. It has been found that residual subsidence of the old goaf presents obvious periodicity, and each cycle shows certain characteristics; in the same goaf, there are equal or approximately equal notable periodicity and duration time in different observation points.(5) Aiming at the character of random fluctuation of residual subsidence sequence of old goaf, three prediction models of it were presented in this dissertation, including wavelet support vector machines (WT-SVM), grey Markov prediction model (GM-Markov) and discrete grey model of 2 order 2 variables (DGM(2,2)), which was applicable to predict the length of observation sequence l conforming to the requirements of l≥20, 10≤l<20 and 6≤l<10 respectively. Meanwhile, the corresponding prediction step should limit within l/5, 4 and 2 respectively.(6) Height prediction of water fractured zone based on fuzzy SVM was brought forward. According to the prediction value, stability of the old goaf could be concluded by the criterion, namely, the old goaf is steady if the influential depth does not reach the water fractured zone. Moreover, stability evaluation of old goaf based on fuzzy extension model was proposed to estimate whether the old goaf was suitable for buildings or not. A case study was given in this dissertation and the results indicated that the two methods mentioned above and residual subsidence prediction based on amended probability-integral method could be adopted to evaluate the old goaf stability effectively.There are 66 figures, 47 tables and 202 references in this dissertation.更多还原