Research of the prediction method and environment conservation due to coal mining subsidence in North China

为了解决采矿引起的沉陷问题，我们与国内领先的研究机构合作开展了这个项目。在合作期间，我们邀请中国研究人员到日本，并派我们的研究人员到中国调查沉降的现状。总结了调查研究结果。由于中国的煤矿开采大多为地下开采，人们认为地面沉降是不可用的。受影响面积约为1.33 ~ 2亿m^2，呈逐年递增趋势。一般来说，对地表结构的相应影响如下：沉降、坡度、曲率、水平运动和纵向应变。事实上，每一个影响因素都是交替作用的。在中国的许多地区，有许多低坡度河床的河流。沉降可能影响整个流域，并可能产生排水等问题。九州大学开发了一种新的利用地理信息系统（GIS）预测沉降过程的分析系统。该方法已在华北两个有代表性的地区得到应用。对开挖过程引起的沉降进行了精确预测，并对铁路、桥梁等地面结构的影响进行了评价。提出了一些思路，并对开挖规划进行了修改，以减小沉降影响。在煤矿开采的开挖规划中，要正确评价相应的影响和影响，并制定相应的对策。本文的研究成果可用于构建地质环境保护体系，实现资源与环境的和谐发展。

In order to solve subsidence problem due to mining, we cooperate with the leading research institutes in China to carry out this project. During the cooperation, we invite the Chinese researchers to Japan, and send our researchers to China to investigate the current status of subsidence. The investigation and studied results are summarized.Because most of the coal mining in China is underground mining, it is believed that the subsidence is unavailable. The influenced area is about 133〜200 million m^2 increasing every year. Generally, the corresponding influences to the surface structure are discussed as follows : subsidence, slope, curvature, horizontal movement and longitudinal strain. In fact, each influencing factor works alternatively. In many areas, there are a lot of rivers with a low gradient riverbed in China. Subsidence may influence the whole watershed area and some problems such as drainage may take place. Kyushu University has developed a new analysis system to predict the subsidence procedure by using Geographic Information System (GIS). The method has been applied to two representative districts in North China. The subsidence because of excavation process is precisely predicted, and its influences to surface structure such as the railway and bridge are assessed. Some ideas have proposed and the excavation planning is modified to reduce the subsidence impact.In the excavation planning of coal mining, the corresponding influences and impact should be evaluated correctly and the corresponding counter measures have to be prepared. Concerning the theme of creating a good new environment nowadays, the research results could be used to establish a geo-environment conservation system, and the development of resources could be in harmony with the environment.