配比煤水力压裂起裂特性研究及破裂效果分析

发布时间：2018-06-17 23:28

本文选题：水力压裂 + 起裂压力　；参考：《安徽理工大学》2017年硕士论文

【摘要】：水力压裂技术广泛应用于多个工程领域且已得到有效发展。在煤矿开采中,水力压裂技术通过向煤层中注入高压水破碎煤体、浸润煤体,促使煤体冲击危险性向深部转移,达到有效缓解冲击地压的目的。由于现场水力压裂技术具有不可重复性,近年来学者将研究焦点转向实验室,然而实验室实验的不完善、可靠性以及实验结果缺少评价成为本文的研究重点。本文采用理论研究、实验研究和数值模拟分析的方法进行水力压裂实验研究,一方面对水力压裂实验进行补充,另一方面通过理论分析和数值模拟的比较验证实验的可靠性,并对实验进行探索性评价,主要包括以下内容:(1)实验室水力压裂实验通过仪器合理布置与实验的前期处理保证试样能顺利进行,同时通过同种材料不同配比得出的不同单轴抗压强度的试样,且随着单轴抗压强度的增加水力压裂实验的试样起裂压力升高。(2)通过水力压裂实验过程中的水压检测与试样起裂过程观察,得出不同单轴抗压强度试样在水力压裂不同阶段的试样表面渗透情况与水压变化过程各阶段之间的关系,同时观察得到不同配比的试样其水压升高、起裂以及破裂的时间特点;(3)通过ANSYS模拟软件输出的数据与实验中各阶段数据的计算结果误差较小,为1.33%、0.98%、0.87%,因此可认为实验结果是较为准确且实验并没有破坏试样的断裂力学性能,证明了实验的准确信,确保了实验的可信度。(4)通过多组实验的数据整理和记录,通过能量法与面积分数法的相互验证,得出同种配比的试样其起裂效果随着起裂压力的升高,能量释放越充分、破裂面面积分型维数越大,裂隙发育效果越好。
[Abstract]:Hydraulic fracturing technology is widely used in many engineering fields and has been developed effectively. In coal mining, hydraulic fracturing technology by injecting high pressure water into the coal seam to break coal body, infiltrate coal body, promote the coal body impact risk to the deep transfer, to achieve the purpose of reducing the impact ground pressure effectively. Because the field hydraulic fracturing technology is not repeatable, in recent years, the research focus has been turned to the laboratory. However, the imperfection, reliability and lack of evaluation of the experimental results have become the focus of this paper. In this paper, theoretical research, experimental research and numerical simulation analysis are used to study the hydraulic fracturing experiment. On the one hand, the hydraulic fracturing experiment is supplemented; on the other hand, the reliability of the experiment is verified by theoretical analysis and numerical simulation. And the exploratory evaluation of the experiment includes the following contents: 1) the hydraulic fracturing experiment in the laboratory can be carried out smoothly through the reasonable arrangement of the instrument and the preliminary treatment of the experiment. At the same time, the specimens with different uniaxial compressive strength obtained from different proportions of the same material, With the increase of uniaxial compressive strength, the fracture initiation pressure of hydraulic fracturing test samples is increased. The relationship between the surface permeability of samples with different uniaxial compressive strength at different stages of hydraulic fracturing and each stage of hydraulic pressure change is obtained. At the same time, the water pressure of samples with different ratios is observed. The time characteristics of crack initiation and rupture are as follows: (1) the error between the data output by ANSYS simulation software and the data of each stage in the experiment is relatively small, which is 1.330.98 / 0.87. therefore, it can be considered that the experimental results are more accurate and do not destroy the fracture mechanical properties of the specimens. The accuracy of the experiment is proved, and the reliability of the experiment is ensured. (4) through the data collation and recording of many groups of experiments and the mutual verification of the energy method and the area fraction method, it is concluded that the initiation effect of the specimen of the same proportion increases with the initiation pressure. The more energy is released, the larger the integral dimension of fracture surface is, and the better the effect of fracture development is.
【学位授予单位】：安徽理工大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TD712.6

【参考文献】