格值分段计算重力单程观测,三程循环观测法的公式

总结了大测程重力仪分段标定的格值相对变化大于/1400时,单程、三程循环重力观测值居于不同测程段内可能出现的8种计算公式.     

总结大测程重力仪的分段格值整理重力资料的几种情况

对于大测程重力仪,当分段标定的格值相对变化大于1/1 400时,应使用分段格值对重力资料进行整理.文中总结了如何使用重力仪的分段格值计算在不同测程段上观测点重力值可能出现的几种情况.     

岩层真厚度计算公式述评：兼与佟再三,佟洁,许边远同志商榷

从列昂托夫斯基的三个传统公式到沈忠悦的一个通用公式,使岩层真厚度计算简便得多。但沈氏公式中带有绝对值,所以当连续测量地层剖面而进行厚度累计时容易出错。虽然文朴、徐开礼讨论了负厚度问题,但仍需人工选择不同公式计算或判断正负号,甚至出现文中规定的正负号变换原则与实际情况相矛盾的情形。由此可见,岩层真厚度计算的关键问题乃是厚度值的正负问题,即负厚度的识别和负号的应用。笔者等曾规定,导线从岩层下层面往上层面方向前进时所控制的岩层厚度为正厚度,导线从岩层上层面往下层面方向前进时所控制的厚度为负厚度,并在沈忠悦公式的基础上,根据岩层面法线与导线之情况相符,选择的参数可直接取自野外实测数据,避免了过程性人工换算环节。     

多硅白云母晶体化学式几种方法的讨论 ——用电子探针数据计算

根据多硅白云母晶体化学模型的特点，比较了几种白云母晶体化学式的计算方法，提出的化学计量性方法，较合理地反映了多硅白云母晶体化学模型的特点，并解决了电子探针分析数据中Fe^3 /Fe^2 的问题。     

利用抗剪强度计算地基承载力特征值方法探讨

利用不同地层情况的计算实例,分别采用抗剪强度指标厚度加权平均法和附加应力面积法对地基承载力特征值进行计算,对计算结果进行分析,对不同的计算方法的理论原理进行了剖析,提出利用附加应力系数法计算抗剪强度指标标准值的结论。同时提出抗剪强度指标应采用不固结不排水剪指标,当持力层为粉土时应对其抗剪强度指标进行75%的折减的方法和建议。为合理利用抗剪强度指标计算地基承载力特征值提供了有益的参考。     

Discussion on the calculation of the rights protection radius of the geothermal well for stratified thermal reservoir

In order to ensure the sustainable exploitation of geothermal resources and prevent the occurrence of thermal breakthrough during the process of geothermal water reinjection, the authors systematically summarized the calculation formulas of the rights protection radius of the geothermal well in this paper. Three shortcomings in the calculation method of the rights protection radius of the geothermal well were identified through theoretical derivation. (1) The parameter f, which is defined as the ratio of the specific heat of water to that of thermal reservoir rocks, is defective. (2) The value of the thermal reservoir recovery rate defined as 0.15 is relatively unilateral, which is not applicable for geothermal wells with different lithology. (3) The calculation time is fixed as 36 500 d, which is not appropriate for geothermal wells with interval development. Based on the problems above, the authors redefined the parameter f and used variables to replace the previous thermal reservoir recovery rate and exploitation time, which can be identified according to different thermal reservoirs and specific exploitation time. By comparison of the applicable conditions of different calculation formulas of the rights protection radius of the geothermal well, the authors proposed that different calaulation formuas should be chosen based on the relationship of the size between β^-1-α and 3λ. And by comparison of the rights protection radius calculation formulas for the mining well and the recharge well, it is found that the rights protection radius of the mining well is always bigger than that of the recharge well. Finally, Shuiwen residential area of Decheng district was taken as an example to verfity the theoretical results.     

层状热储地热井权益保护半径计算探讨

为保证地热资源的可持续开采,防止地热尾水回灌时发生热突破现象,文章系统整理了地热井权益保护半径的计算方法。通过理论推导,发现开采井权益保护半径的计算方法有3个不足之处: (1)公式中参数f定义为水比热与热储岩石比热的比值,存在缺陷; (2)热储回收率取值0.15,较为片面,不能代表不同岩性热储回收率的取值; (3)计算时间固定为36 500 d,较为片面,不适用于地热井间歇开采期。针对上述问题,该文重新给定了参数f的定义,并将热储回收率和开采时间以变量符号替代,可根据不同热储层和具体开采时间加以确定。通过研究不同回灌井权益保护半径计算方法的适用条件,提出应根据(β^-1-α)与3λ的大小关系选择不同的计算公式。对开采井和回灌井权益保护半径计算公式进行对比,发现开采井权益保护半径恒大于回灌井权益保护半径,并以德城区水文家园开采系统和回灌系统为例进行计算,验证了理论推导的结果。     

Comparative Seismic Risk Studies for German Earthquake Regions on the Basis of the European Macroseismic Scale EMS-98

Within the framework of recent research projects, basic tools for GIS-based seismic risk assessment technologies were developed and applied to the building stock and regional particularities of German earthquake regions. Two study areas are investigated, being comparable by the level of seismic hazard and the hazard-consistent scenario events (related to mean return periods of 475, 2475 and 10000 years). Significant differences exist with respect to the number of inhabitants, the grade and extent of urbanisation, the quality and quantity of building inventory: the case study of Schmölln in Eastern Thuringia seems to be representative for the majority of smaller towns in Germany, the case study of Cologne (Köln) stands for larger cities. Due to the similarities of hazard and scenario intensities, the considerable differences do not only require proper decisions concerning the appropriate methods and acceptable efforts, they enable conclusions about future research strategies and needs for disaster reduction management. Not least important, results can sharpen the focus of public interest. Seismic risk maps are prepared for different scenario intensities recognising the scatter and uncertainties of site-dependent ground motion and also of the applied vulnerability functions. The paper illustrates the impact of model assumptions and the step-wise refinements of input variables like site conditions, building stock or vulnerability functions on the distribution of expected building damage within the study areas. Furthermore, and in contrast to common research strategies, results support the conclusion that in the case of stronger earthquakes the damage will be of higher concentration within smaller cities like Schmölln due to the site-amplification potential and/or the increased vulnerability of the building stock. The extent of damage will be pronounced by the large number of masonry buildings for which lower vulnerability classes have to be assigned. Due to the effect of deep sedimentary layers and the composition of building types, the urban centre of Cologne will be less affected by an earthquake of comparable intensity.