城市地质条件适宜性评价是支撑城市规划建设区控制性详细规划编制和工程建设前期开展的专项地质调查工作.北京地区调查评价内容包括地形地貌、水文地质、工程地质等3项基础地质条件,活动断裂、地面沉降、地裂缝、崩塌、滑坡、泥石流、采空塌陷、岩溶塌陷、砂土液化、地下水污染、土壤污染等11项地质环境要素,地下水资源、深层地热资源、浅层地热能等3项地质资源要素.在现有标准基础上,结合北京地区城市地质工作实践,新建了1:10000和1:2000精度城市地质条件调查方法体系,并设定了工作布置参数;构建了城市地质条件评价指标体系,包括61项评价指标,其中新增指标20项、修订指标31项、引用现有标准指标10项.

城市地质资源环境承载力要素监测是城市发展中后期的重要基础性工作.监测体系建设的目标是全面掌握地质要素变化规律,为城市发展安全提供保证.该体系建设的总体思路是基础坚实、问题明确、平面分区、纵向分层、立体成网、全面采集、可靠传输、云端存储、抓住奇点、把握关联、构建模型、预测趋势、多级服务、有效应用.该体系的基础是数据采集系统,核心是分析系统,关键是应用系统.该体系的建设运行,可有效地提高城市地质安全保证水平.本文以北京市为例介绍了地质资源环境监测体系建设的实践.

In the operation of connecting brine wells,whether the connection is successful depends on the precision of the directional wells on the one side,and on whether the setting up of solution cavities in the straight wells satisfies the designed requirements (usually called building a slot) on the other side.If the building of a slot fails to strictly match the specifications of the design,then the difference between the actual solution cavity and the calculated results may result in failures in the connction of wells and repetition of operations.The design and calculation of solution cavities are related to the thickness of the target (salt) layer,the dip angle and the methods of brine mining.

北京市地质工程设计研究院前身是北京市地矿局101地质队.自1958年成立以来,曾荣获国家地质总局"大庆式企业"、原地矿部"地质找矿重大贡献奖"、"国家功勋地质队"等称号.

As the development of city construction, more and more high-rise buildings emerge in dense down town. Due to the narrow space of engineering and dense underground pipe nets, the spaces which can be used to construct become even smaller. Meanwhile the safety of around buildings should be taken into account while excavating the foundation pit. The contracy construction method of deep foundation pit successfully resolved the problems mentioned above. The main technical peculiarities, main technical measures and their existing problems of the contrary construction method were further discussed after the working principles of the method were clarified.

降水对逆作法施工尤为重要.逆作法施工中通常采用坑内深井井点降水,而在北京王府井大厦工程中充分利用了场地的水文地质条件,大胆地采用了自渗井点降水,取得了良好的降水效果,经济、社会效益显著.