【作者】 杜荣军；

【导师】 夏玉成；

【作者基本信息】 西安科技大学 ， 矿产普查与勘探， 2008， 硕士

【摘要】 国内外关于采煤沉陷机理及其规律的研究已经取得了大量的研究成果,但由于对地质因素考虑不周,对采煤沉陷与地质因素之间量化关系的研究程度较低,目前已经取得的相关研究成果,还不能满足在采前对开采沉陷进行准确预计的要求。本文主要通过计算机数值试验,提取出在一定开采条件下构造介质、构造界面、构造应力等地质因素与采煤沉陷的关系数据,然后利用支持向量机软件,构建上述地质因素与地表最大下沉值之间的量化关系式。本文研究工作取得以下主要成果:在不考虑构造界面和构造应力情况下,如果采深（覆岩厚度）保持不变,松散层厚度与地表最大下沉值正相关,基岩层厚度与地表最大下沉值负相关。覆岩综合硬度和土岩比是能够综合反映构造介质（覆岩）厚度特征和硬度特征的两个因素,前者与地表最大下沉值负相关,后者与地表最大下沉值正相关。在没有煤层覆岩中各个岩层的物理力学参数,因而无法准确计算覆岩综合硬度的情况下,可利用土岩比代表构造介质特征对采煤沉陷进行预计。土岩比与地表最大下沉值的量化公式如下:f₄（x） = -80.54*（0.49x+1）¹⁰+80.54*（0.06x+1）¹⁰-524.8776在不考虑构造应力情况下,以RFPA软件中的均值度模拟节理密度,随着均值度增加,即节理密度减小,地表最大下沉值相应减小。随着节理倾角增加,地表最大下沉值先减小后增大,其最小值对应的节理倾角在40°～50°间,且节理倾角不同,地表最大下沉点出现的位置有所不同。在不考虑构造界面影响的情况下,随着挤压应力的增大,地表最大下沉值减小,但下沉范围有所扩大。在节理倾角一定的情况下,随着挤压应力的增大,地表最大下沉值减小;在相同强度的挤压应力作用下,随着节理倾角增大,地表最大下沉值先减小后增大。在逆断层倾角、落差一定时,随着挤压应力的增大,地表最大下沉值减小,地表下沉盆地范围则有所增大;在一定强度的挤压应力作用下,随着逆断层落差的增加,地表最大下沉值增加。在正断层倾角、落差一定的情况下,随着拉张应力的增加,拉张应力区的分布范围扩大,地表最大下沉值增大,下沉盆地的范围则无明显变化。更多还原

【Abstract】 As so far now, the mechanisms and the regularity of how geological factors influencing the mining subsidence had been studied a lot, but due to the geological factors had not been fully considered, so the quantitative relation between these factors and the mining subsidence had little been realized, and the research achievement at present can’t meet the demand of accurate prediction before the mining activities. So by means of numerical test, this paper got the date between the geological factors, such as tectonic medium, interfaces and stresses, and mining subsidence under some certain mining conditions. At last, the quantitative relations were established. The main results were as following :Without considering structural interfaces and tectonic stresses, when the mining depth was certain, the losses thickness had a negative relation with the ground maximum subsidence value, and the relation was positive between the bedrocks thickness and the maximum subsidence value. The comprehensive hardness of overburdens and the ratio of soil and rock thicknesses could be used to reflect the thickness and hardness characteristics of tectonic medium, and the former had a negative relation with the ground maximum subsidence value, the latter had a positive relation. If the phicical and mechanical parameters of overlying strata couldn’t be obtained, then the comprehensive hardness of overburdens couldn’t be actually calculated, under this situation, the ratio of soil and rock thicknesses could be used to predict the mining subsidence as the main structural medium factor, and the quantitative relation between the ratio and the maximum subsidence value was as following :f₄（x） = -80.54*（0.49x+1）¹⁰+80.54*（0.06x+1）¹⁰-524.8776Without tectonic stresses’s influencing, letting average degree of rock represent the joint density in RFPA numerical software, when the average degree of rock increased, the joint density would reduce meanwhile, and the maximum subsidence value would reduce accordingly. As for the joint’s angle, the maximum value would decrease firstly and then increase, the minimum appeared when the joint angle was between 40 degree and 50 degree, and the position of the maximum value in the groud was different as the angle changed.For the tectonic medium without interfaces, with the increasing of compressive stresses value, the groud subsidence value would reduce while the scope would enlarge. For the overburden obtaining joints, the maximum subsidence value would reduce when the angle was fixed but the compressive stress value increased, and the maximum subsidence value would reduce firstly and then increase when the compressive stress value was fixed but the angle increased. For the reverse fault, the maximum subsidence value would reduce with the subsidence scope enlarging when the drop and angle were fixed, and the maximum subsidence value would increase with the drop’s increasing when the compressive stress was certain. When it was to the normal fault, with the increasing of tensile stress value, the distribution scope of tensile stress area enlarged, the maximum subsidence value increased, but the scope of subsidence basin had little change.更多还原