基于分层标监测的德州城区地面沉降分层沉降特征浅析

自20世纪80年代开始,由于地层结构松散、固结程度低,地下水超采等原因,鲁西北平原区地面沉降持续发展。年沉降速率最快的区域位于东营南部的广饶县、滨州南部的博兴县和聊城东部的茌平区附近。德州地面沉降漏斗与周边沧州、衡水沉降区连成一片,成为鲁西北平原区最为典型的地面沉降发育区。其中德州城区国棉厂监测点1991—2017年累计沉降量已超过1400mm。该文简要介绍了德州分层标组施工工艺、监测方法,综合利用水准测量及分层标监测数据,开展了分层沉降特征研究,查明分层标组所在区域0～60m,60～300m,300～500m及500m以深地层因压缩变形引起的地面沉降速率分别为1.67mm/a,20mm/a,18.33mm/a,8.00mm/a。对引起地面沉降的主要因素进行了简要分析,对德州城区地面沉降监测工作提出了建议。

Analysis on Characteristics of Layered Settlement of Land Subsidence in Urban Area of Dezhou City Based on Layering Marks Monitoring

Since 1980s, due to loose structures, low degree of consolidation, and over exploitation of groundwater, land subsidence in the northwestern plain of Shandong province has been developing continuiously. The area with the fastest annual settlement rate is located in Guangrao county in the south of Dongying, Boxing county in the south of Binzhou and Muping district in the east of Liaocheng. Ground subsidence funnel in Dezhou is connected with the surrounding Cangzhou and Hengshui settlement areas, and becomes the most typical land subsidence development area in the northwestern plain of Shandong. Among them, the accumulated settlement of the National Cotton Factory monitoring point in Dezhou city has exceeded 1400mm from 1991 to 2017. In this paper, the construction process and monitoring method of the layering marks in Dezhou has been briefly introduced. By using leveling and layering marks monitoring data comprehensively, research on the characteristics of layered settlement has been carried out. It is identified that the ground subsidence rates in the depth of 0~60m, 60~300m, 300~500m and 500m due to compression deformation are 1.67mm/a, 20mm/a, 18.33mm/a and 8.00mm/a respectively. Main factors which caused land subsidence have been analyzed briefly, and suggestions have been put forward for the monitoring of land subsidence in the urban area of Dezhou city.