降雨对徐州地震台体应变观测干扰显著。为研究降雨干扰的基本特征，明确其影响机制，建立符合该测点的数值模型，就含水层导水系数、渗透率、降雨系数开展数值模拟，对降雨干扰进行定量分析。结果表明：2020年以来，该台体应变降雨系数明显增大，降雨响应时间缩短、响应幅度增大；基于体应变降雨积累模型进行数值模拟，可知在降雨量75—120 cm的常见降雨事件中，该台含水层渗透系数K值在6.4—24.1 mm/h范围内分布密度较大，若K值取为核密度平均值，即K = 15.5 mm/h时，拟合结果更接近真实形变变化，二者的相关系数均在0.8以上，模型响应效果较好。
Rainfall significantly interferes with the body strain observation at Xuzhou Seismic Station. In order to study the basic characteristics of rainfall interference, clarify its influence mechanism, establish a numerical model conforming to the measurement point, carry out a numerical simulation of aquifer water conductivity, permeability, and rainfall coefficient, and conduct quantitative analysis of rainfall interference. The results show that the rainfall coefficient for the strain at the station has increased significantly since 2020, and the rainfall response time has shortened, and the response amplitude has increased. The numerical simulation based on the rainfall accumulation model of body strain shows that in common rainfall events with rainfall of 75-120 cm, the distribution density of the aquifer permeability coefficient K value is relatively large in the range of 6.4-24.1 mm/h. If the K value is taken as the average nuclear density, that is, K = 15.5 mm/h, the fitting result is closer to the true deformation change. The correlation coefficients of both are above 0.8, and the model has a good response effect.
2023,44（6）: 109-115 收稿日期：2023-6-19
DOI：10.3969/j.issn.1003-3246.2023.06.016
基金项目：中国地震局监测、预测、科研三结合课题（项目编号：3JH-202301035）
作者简介：郝冉（1991—），男，工程师，主要从事定点形变观测与研究工作。E-mail：haoran910106@163.com
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