In the paper, we analyze 117 moderate-strong earthquakes occurred in Chinese mainland (Ms greater than or equal 5.5 in the east and Ms greater than or equal 6.0 in the west) since 1970, among them, 11 earthquakes (abo...In the paper, we analyze 117 moderate-strong earthquakes occurred in Chinese mainland (Ms greater than or equal 5.5 in the east and Ms greater than or equal 6.0 in the west) since 1970, among them, 11 earthquakes (about 9%) have direct foreshocks and 63 earthquakes (about 51%) have generalized foreshocks. The predominant time interval between foreshock and main earthquake is no more than 30 days with a spatial distance less than 50 km and a magnitude difference over 1. From the digital seismic data in Liaoning Province, we know that direct foreshock had an obvious shear-stress background before the Ms=5.6 and Ms=5.1 Xiuyan earthquakes occurred on Nov. 29, 1999 and Jan.15, 2000.展开更多
Ⅰ. INTRODUCTION The yield criterion or' materials under combined stresses is the important foundation for the research of constitutive law of materials, and widely used in the mechanics of solids, the strength of...Ⅰ. INTRODUCTION The yield criterion or' materials under combined stresses is the important foundation for the research of constitutive law of materials, and widely used in the mechanics of solids, the strength of structures and the elasto-plastic analysis of structures. The three present展开更多
基金Key Project of State Science and Technology in the tenth Five-year Plan (2001BA601B01-01-02).
文摘In the paper, we analyze 117 moderate-strong earthquakes occurred in Chinese mainland (Ms greater than or equal 5.5 in the east and Ms greater than or equal 6.0 in the west) since 1970, among them, 11 earthquakes (about 9%) have direct foreshocks and 63 earthquakes (about 51%) have generalized foreshocks. The predominant time interval between foreshock and main earthquake is no more than 30 days with a spatial distance less than 50 km and a magnitude difference over 1. From the digital seismic data in Liaoning Province, we know that direct foreshock had an obvious shear-stress background before the Ms=5.6 and Ms=5.1 Xiuyan earthquakes occurred on Nov. 29, 1999 and Jan.15, 2000.
基金Project supported by the National Natural Science Foundation of China
文摘Ⅰ. INTRODUCTION The yield criterion or' materials under combined stresses is the important foundation for the research of constitutive law of materials, and widely used in the mechanics of solids, the strength of structures and the elasto-plastic analysis of structures. The three present
