地质统计学在地层岩土参数分布规律研究中的应用

发布时间：2019-06-21 21:45

【摘要】：随着改革开放的日益深入,房地产业在市场经济中占据着日趋重要的地位,并长期受到全社会的广泛关注。尤其近几年来,城市建设的步伐不断加速,高层超高层建筑越来越多,旧城改造新建楼房也是见缝插针。建筑业的蓬勃发展也带动了相关领域工程技术的不断进步,如基础勘测、基坑工程、地下工程、地基处理等等。加强对地层空间不确定性因素与确定性因素的研究是实现工程建设稳步进行的根本途径。在我国经济富庶的东南沿海地区,地层土壤空间分布规律是制约土地规划和工程建设的重要因素,同区域环境一起影响着该区土地利用和经济发展。在区域尺度下,对于整个研究区域地块内地层岩土参数空间分布特征及其影响因素进行系统而科学地认识,是工程顺利实施的有力保证,对区域单元上的宏观决策问题具有重要的指导作用。本论文以典型的滨海相沉积地层为研究区域,旨在摸清现阶段主要地层参数的整体变异状况,明晰其空间变异特征及空间分布格局,并揭示不同尺度下地层岩土参数与相关环境因素之间的关系。本论文岩土参数取自《江苏省阜宁县向阳花苑1#~22#楼勘探报告》,主要研究地层有第3层淤泥质粉质粘土层,计有43个勘探孔;第8层粉质粘土层,计有43个勘探孔,层厚4.0~5.3m;第9层粘土层,计有29个勘探孔。采用经典统计学(整体特征变异、方差比较、均值分析等)、地质统计学(变差函数、克里格空间插值)、状态空间数值模拟等方法,对各主要研究地层岩土参数的空间变异特征、空间数值模拟及预测、不同研究尺度下的相关影响因素进行了细致的分析,现将主要研究结果列示如下:(1)研究区域地层岩土参数的含量整体变化水平在本区域处于中等偏弱变异水平。地质统计学分析表明,淤泥质粉质粘土层岩土参数液限、塑限、液性指数为中等变异参数,块金系数小于0.25;粉质粘土地层参数表现为中等变异的有孔隙比、压缩模量,块金系数在0.25~0.75之间;粘土层地层岩土参数表现为中等变异的有压缩模量,X方向与Y方向块金系数在0.25~0.75之间。变异函数分析比较发现,各主要地层岩土参数在区域勘测尺度上无明显各向异性。(2)本文研究了地层岩土参数间的空间相关性规律:淤泥质粉质粘土地层含水率与孔隙比存在强正相关关系,相关系数0.9410,压缩系数与压缩模量存在强负相关关系,相关系数-0.9450;含水率、孔隙比、液性指数、压缩系数等参数指标在不同方向上存在较好的空间协相关性,X方向变程a接近于5.7m,Y方向变程a接近于7.1m;含水率和孔隙比自相关性较好,全局变程值范围设为7m。粉质粘土地层含水率与孔隙比、液性指数为强正相关关系,相关系数大于0.73,压缩系数与压缩模量为负相关关系,负相关系数为-0.9527;含水率与液性指数、压缩系数指标在不同方向上存在较好的空间协相关性,其相互协相关性变程值均接近于5 m;液限、塑限、压缩模量存在着较强的空间自相关性,其全局变程值可设为7 m。粘土地层含水率与孔隙比、液限、塑限间存在较强的正相关关系;液限与塑限、塑性指数间存在较强的正相关关系;粘土地层含水率与孔隙比、液限、塑性指数、液性指数等参数指标在不同方向上的变化有着较好的空间协调性,其协相关性变程值可确定为5.5 m;含水率、液限、塑限、塑性指数、液性指数有着较强的空间自相关性,其全局变程值可设为6 m。(3)相关地层岩土参数尺度下的研究及最优尺度的选择分析表明,含水率、液性指数、压缩系数的变差函数模型,在不同的尺度下不具有可比较性。含水率、液性指数、压缩系数的空间变化对各个尺度的响应各不相同;含水率与压缩系数的空间最优尺度设为8 m为宜,液性指数设为10 m为宜。(4)对研究区域内不良地层的研究,重点阐述了地质统计学在勘测设计与施工中的应用。分析表明,淤泥质土地层液限、塑限、液性指数变异性较大,应加密勘测;不同方向空间变异规律研究显示,淤泥质土地层Y方向的空间变异性较大,对该方向应进行重点勘测。通过最优无偏空间插值,即克里格插值,绘制了主要地层压缩系数空间分布图,对指导进一步的勘测设计与施工有一定的实际应用意义。(5)区域尺度上,自然因素,如大气降水、明塘、暗塘、河流分布、土壤组成成分等,对地层岩土参数具有显著影响;人为因素,如勘测误差、实验测试方法,与上述自然因素之间也存在相互关系,并显著影响各岩土参数指标。整体来看,地层土壤参数指标具有中等偏弱的空间变异性,分布较为稳定。本文以大量的野外勘测数据为研究基础,从整体上明晰了滨海相沉积地层土壤参数如含水率、孔隙比、液限、液性指数、塑限、塑性指数、压缩系数以及压缩模量的空间变异特性及其与相关环境因素之间的内在联系。可靠的地层参数空间数据丰富了滨海相沉积地区数据库,为该区土壤参数指标空间变异及相关研究的深入开展提供了整体框架指导,也为今后该区大尺度上数字土壤制图、地层沉积模拟、地质环境评估等提供了可靠的数据支持,相关研究结果也将为研究区域各项建设工程的宏观决策提供理论和实践指导。
[Abstract]:With the deepening of the reform and opening-up, the real estate industry occupies an increasingly important position in the market economy, and has been widely concerned by the whole society for a long time. In recent years, the pace of urban construction has been accelerating, and the high-rise and super-high-rise buildings have become more and more, and the new building in the old city is also a joint pin. The development of construction industry has also led to the progress of engineering technology in the relevant fields, such as foundation survey, foundation pit engineering, underground engineering, foundation treatment and so on. It is the fundamental way to strengthen the steady progress of the project construction by strengthening the study of the factors of the uncertainty of the formation space and the deterministic factors. In the southeast coastal area of China's rich economy, the distribution of the spatial distribution of the formation soil is an important factor to restrict land planning and engineering construction, and the land use and economic development of the region are affected with the regional environment. In the regional scale, the systematic and scientific understanding of the spatial distribution characteristics and the influencing factors of the formation rock and soil parameters in the whole area of the study area is a strong guarantee for the smooth implementation of the project, and has an important guiding role on the macro-decision problem on the regional unit. In this paper, a typical sea-sea facies sedimentary formation is used as the research area. The purpose of this paper is to find out the overall variation of the main formation parameters in the current stage, to clarify its spatial variation and spatial distribution pattern, and to reveal the relationship between the rock-soil parameters and the related environmental factors at different scales. The geotechnical parameters of this paper are taken from the exploration report of 1 # ~ 22 # building in FuNing County, Jiangsu Province. The main research strata include the third layer of silty clay layer, including 43 exploration holes, and the 8th layer of silty clay layer, including 43 exploration holes, with the layer thickness of 4.0-5.3m, and the 9th layer of clay layer. There are 29 exploratory holes. The spatial variation characteristics, spatial numerical simulation and prediction of the rock and soil parameters are mainly studied by the methods of classical statistics (overall feature variation, variance comparison, mean analysis, etc.), geostatistics (variogram, Kriging space interpolation) and state space numerical simulation. The main results of the study are as follows: (1) The overall change level of the soil parameters in the study area is at a moderate and weak variation level in the region. The geological and statistical analysis shows that the rock-soil parameter liquid limit, the plastic limit and the liquid-liquid index of the silty clay layer are medium variation parameters, the block gold coefficient is less than 0.25, the formation parameters of the silty clay are medium-variation with the porosity ratio, the compression modulus and the block gold coefficient between 0.25 and 0.75; The rock-soil parameters of the clay-layer formation are medium-variant with compressive modulus, and the coefficient of gold in the X-direction and the Y-direction is between 0.25 and 0.75. The analysis of the variation function shows that the geotechnical parameters of the main formation have no significant anisotropy in the regional survey scale. (2) The spatial correlation of the formation rock and soil parameters is studied in this paper. There is a strong positive correlation between the water content of the silty clay formation and the pore ratio, the correlation coefficient is 0.9410, the compression coefficient and the compression modulus have a strong negative correlation, the correlation coefficient is 0.9450, the water content and the pore ratio, The parameter indexes such as the liquid index and the compression coefficient have good spatial corelation in different directions. The direction of X direction is close to 5.7 m, and the direction of the Y direction is close to 7.1m; the water content and the aperture ratio are better than the self-correlation, and the global range of the range is set to 7 m. The water content and the porosity ratio of the silty clay formation are strongly positive correlation, the correlation coefficient is greater than 0.73, the compression coefficient is negative correlation with the compression modulus, the negative correlation coefficient is-0.9527, the water content and the liquid index, The compression coefficient index has a better spatial cocorrelation in different directions, and the correlation of the correlation of the covariates is close to 5 m; the liquid limit, the plastic limit and the compression modulus have a strong spatial autocorrelation, and the global variation value can be set to 7 m. The water content of the clay formation is equal to the pore ratio and the liquid limit, There is a strong positive correlation between the plastic limit and the plastic limit, there is a strong positive correlation between the liquid limit and the plastic limit and the plasticity index, the water content of the clay formation and the pore ratio, the liquid limit, the plasticity index, the liquid index and other parameters have better spatial coordination in different directions, The value of its cocorrelation can be determined to be 5.5m; the water content, liquid limit, plastic limit, plasticity index and liquid index have a strong self-correlation, and the global variation value can be set to 6 m. (3) The research on the scale of the relevant formation rock and soil parameters and the selection analysis of the optimal scale show that, The variation function model of water content, liquid index and compression coefficient is not comparable at different scales. The spatial variation of the water content, the liquid index and the compression coefficient is different to the response of the various scales; the optimal size of the space between the water content and the compression coefficient is 8 m, and the liquid permeability index is 10 m. (4) The application of the geostatistics in the design and construction of the survey is mainly discussed in the study of the bad formation in the study area. The analysis shows that the soil layer liquid limit, the plastic limit and the liquid index variability of the silty soil layer are large, and the survey should be carried out; the spatial variability of the spatial variation in different directions shows that the spatial variability in the Y direction of the silty soil layer is large, and the focus survey should be carried out in this direction. By using the optimal unbiased space interpolation, that is, the Kriging interpolation, the spatial distribution of the main formation compression coefficient is drawn, and it is of practical significance to guide the further investigation and design and construction. (5) The natural factors, such as the atmospheric precipitation, the open pond, the dark pond, the river distribution, the soil composition and the like on the regional scale, have a significant influence on the rock and soil parameters of the formation; human factors, such as survey errors, experimental test methods, and the above-mentioned natural factors also have a mutual relationship, And the indexes of the rock and soil parameters are obviously affected. As a whole, the soil parameters of the formation have moderate and weak spatial variability, and the distribution is more stable. In this paper, based on a large number of field survey data, the soil parameters such as water content, pore ratio, liquid limit, liquid index, plastic limit and plasticity index are clearly defined. The spatial variation of compression modulus and the compression modulus and the internal relationship with the related environmental factors. the reliable formation parameter spatial data enriches the database of the shore-and-sea-phase deposition area, provides an overall framework guide for the further development of the spatial variation of the soil parameter index in the area and the related research, and also provides a digital soil mapping and formation deposition simulation in the large scale in the future, The geological environment assessment and so on provide reliable data support, and the relevant research results will also provide theoretical and practical guidance for macro-decision-making of various construction projects in the study area.
【学位授予单位】：苏州科技学院
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TU43

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