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土体龟裂是一种常见的自然现象,会对土体的工程性质产生显著的负面影响,是许多工程地质和环境地质问题的直接诱因,要研究龟裂,首先需要解决研究方法问题。基于国内外近些年围绕龟裂所开展的工作,着重对研究方法进行了系统的归纳和总结,对比分析了各种方法的优缺点,得到如下认识:(1)土体龟裂研究方法总体分为试验研究和数值模拟研究两大类,试验研究又可分为室内试验和现场试验,目前该课题主要以室内试验为主;(2)室内试验常用的试样主要有泥浆样和压实样两种,且前者更受学界欢迎;(3)土体龟裂试验主要涉及两方面的关键仪器设备,一方面是用于控制试验的环境条件,代表性的为环境箱,另一方面是用于监测龟裂发育过程的相关参数,尤其是裂隙几何形态参数,代表性的有图像采集装置、激光扫描仪、CT机、ERT和分布式光纤等;(4)在试验方法方面,多采用控制变量法研究一个或几个参数对土体龟裂形成及发育规律的影响,包括试样初始状态、尺寸大小、厚度、土质成分、环境温度、相对湿度、试样/容器接触条件和干湿循环次数等;(5)采用数字图像处理技术能快速提取龟裂网络的几何形态结构参数,较其他技术更具前景;(6)现场试验可以最大限度的反映真实裂隙的形成和发育规律,但由于这类试验费时费力投入大等客观原因,报道相对较少;(7)数值模拟是研究土体龟裂的重要手段之一,但由于现阶段关于龟裂发育机制没有统一认识,相关研究还处于起步阶段。最后,针对当前的研究不足提出了今后土体龟裂课题的研究重点。
Soil cracking is a common natural phenomenon that will have a significant negative impact on the engineering properties of soils. It is the direct cause of many engineering geology and environmental geology problems. To study cracks, we must first solve the problem of research methods. Based on the work carried out around the crack in recent years at home and abroad, the research methods are systematically summarized and summarized, the advantages and disadvantages of each method are compared and analyzed, and the following understandings are obtained: (1) Divided into two major categories of experimental research and numerical simulation studies, experimental studies can be divided into indoor tests and field tests, the subject mainly to indoor test-based; (2) commonly used in laboratory test samples are mainly mud-like and compaction And the former is more popular with the academic community. (3) Soil crack test mainly involves two key instruments and equipment, one is used to control the environmental conditions of the test, the representative for the environmental box, on the other hand is For monitoring the development process of crack related parameters, especially fracture geometry parameters, representative of the image acquisition device, laser scanner, CT machine, ERT and distributed optical fiber; (4) in the test methods, the use of more The control variable method is used to study the influence of one or several parameters on the formation and development of soil cracks, including initial state, size, thickness, soil composition, ambient temperature, relative humidity, sample / container contact strip And the number of wet and dry cycles; (5) The digital image processing technology can quickly extract the geometrical structure parameters of the cracked network, which is more promising than other technologies; (6) The field test can reflect the formation and development of real fractures to the maximum extent (7) Numerical simulation is one of the most important methods to study soil cracking. However, due to the lack of uniform understanding of the mechanism of crack development at this stage, Related research is still in its infancy. Finally, according to the current research problems, the research topics of soil cracking in the future are put forward.