基于应力多边形与震源机制解的深部岩体应力状态预测方法初探  

Preliminary investigation on the deep rock stresses prediction method based on stress polygon and focal mechanism solution

作　　者：王璞 王成虎[1] 杨汝华 侯正阳 王洪 WANG Pu;WANG Chen-hu;YANG Ru-hua;HOU Zhen-yang;WANG Hong(Institute of Crustal Dynamics,China Earthquake Administration,Beijing,100085,China;School of Engineering and Technology,China University of Geosciences,Beijing 100083,China)

机构地区：[1]中国地震局地壳应力研究所,北京100085 [2]中国地质大学(北京)工程技术学院,北京100081

出　　处：《岩土力学》2019年第11期4486-4496,共11页Rock and Soil Mechanics

基　　金：国家自然科学基金资助（No.41574088）~~

摘　　要：深部岩体应力量值确定一直是区域地应力场研究中的热点和难点问题,常用的深部岩体应力量值预测方法多以拟合经验公式外推确定为主,缺乏理论依据且可靠性低。研究工作基于应力多边形理论,结合侧压力系数K与震源机制解应力形因子R,在大范围应力预测结果基础之上,对深部应力量值进行了精细限定。以河北易县紫荆关地区的原地应力测量为参考,结合震源机制解资料,估算获得6、11、19km深度处最大侧压力系数Kmax分别为1.07±0.07、1.14±0.14、1.09±0.09,最小侧压力系数Kmin分别为0.85±0.15、0.88±0.12、0.86±0.14,并以此计算最大、最小水平主应力,结果的相对偏差在6%~17%之间;利用震源机制解和水压致裂法联合确定的研究区最大水平主应力方向为N44.4°E。研究提出并建立的联合震源机制参数R和应力多边形限定深部应力状态为深部岩体应力状态估算提供了新的途径。The determination of deep rock stresses is a focused and difficult issue in the study of regional stress field. Most estimating methods for deep rock stresses depend on the extrapolation of fitting empirical formula, which are short of theoretical basis and unreliable. This research proposed the lateral pressure coefficient polygon with reference to stress polygon theory, combined with stress factor R to better constrain stress distribution polygon. The Zijingguan fault belt in Yi county, Hebei province was chosen as the application area. Based on focal mechanism and in-situ stress measurement data in this area, Kmax, the maximum lateral pressure coefficient, and Kmin, the minimum lateral pressure coefficient, were estimated for the deep rock masses of 6 km, 11 km and 19 km respectively. The results showed that Kmax at three depths are 1.07 ± 0.07, 1.14 ± 0.14, 1.09 ± 0.09 and Kmin are 0.85 ± 0.15, 0.88 ± 0.12, 0.86 ± 0.14 respectively. The relative deviation of results is between 6% and 17%. The orientation of the maximum horizontal principal stress, jointly determined by hydraulic fracturing and focal mechanism methods, is N44.4°E. The method proposed and established in this research provides a new estimate means for deep rock stresses.

关 键 词：深部岩体应力状态 紫荆关断裂 应力多边形 应力形因子 水压致裂法 

分 类 号：TU452[建筑科学—岩土工程]