Large-scale shaking table tests were conducted to study the dynamic response of a slope reinforced by double-row anti-sliding piles and prestressed anchor cables. The test results show that the reinforcement suppresse...Large-scale shaking table tests were conducted to study the dynamic response of a slope reinforced by double-row anti-sliding piles and prestressed anchor cables. The test results show that the reinforcement suppressed the acceleration amplification effectively. The axial force time histories are decomposed into a baseline part and a vibration part in this study. The baseline part of axial force well revealed the seismic slope stability, the peak vibration values of axial force of the anchor cables changed significantly in different area of the slope under seismic excitations. The peak lateral earth pressure acting on the back of the anti-sliding pile located at the slope toe was much larger than that acting on the back of the anti-sliding pile located at the slope waist. The test results indicate an obvious load sharing ratio difference between these two anti-slide piles, the load sharing ratio between the two anti-sliding piles located at the slope toe and the slope waist varied mainly in a range of 2-5. The anti-slide pile at the slope waist suppressed the horizontal displacement of the slope surface.展开更多
The Three Gorges Project is one of the essential key projects for flood controlling and water resources regulation in the Yangtze River. The project includes a river-crossing dam, underground powerhouses, and navigati...The Three Gorges Project is one of the essential key projects for flood controlling and water resources regulation in the Yangtze River. The project includes a river-crossing dam, underground powerhouses, and navigation structures. Because of the huge size and complicated construction technologies, the project faced a series of challenging engineering issues. In terms of rock mechanics, there are many key technical issues, including the sliding resistance and stability of the dam section along the foundations of powerhouses No.l-5, the ,,;lope stability of the double-line five-stage shiplock, excavation of large-scale underground powerhouses, and curtain grouting under the dam. With decades of scientific research and 16 years of practical construction experiences and reservoir operations, these key technical issues in construction of the Three Gorges Project are successfully resolved, which will attribute to the development of hydropower technology. On the basis of the monitoring data during construction and normal operation periods of the Three Gorges Project, this paper presents a systematic analysis of these key rock mechanical issues in terms of behaviors, solutions, dynamic controlling, monitoring arrangement and integrated assessment.展开更多
The stability of a gravity dam against sliding along deep-seated weak planes is a universal and important problem encountered in the construction of dams.There is no recommended method for stability analysis of the da...The stability of a gravity dam against sliding along deep-seated weak planes is a universal and important problem encountered in the construction of dams.There is no recommended method for stability analysis of the dam on deep-seated weak planes under earthquake condition in Chinese design codes.Taking Tingzikou dam as an example,the research in this paper is focused on searching a proper way to evaluate the seismic safety of the dam against sliding along deep-seated weak planes and the probable failure modes of dam on deep-seated weak planes during earthquake.It is concluded that there are two probable failure modes of the dam along the main weak geological planes in the foundation.In the first mode,the concrete tooth under the dam will be cut and then the dam together with part foundation will slide along the muddy layer;in the second mode,the dam together with part foundation will glide along the path consist of the weak rock layer under the tooth and the muddy layer downstream the tooth.While there is no geological structure planes to form the second slip surface,the intersection of the main and the second slip surface is 40 to 80 m downstream from dam toe,and the angle between the second slip surface and the horizontal plane probably be 25 to 45 degrees.展开更多
基金financially supported by the National Key R&D Program of China(No.2018YFC1508601)the Fundamental Research Funds for the Central University(20822041B4038)
文摘Large-scale shaking table tests were conducted to study the dynamic response of a slope reinforced by double-row anti-sliding piles and prestressed anchor cables. The test results show that the reinforcement suppressed the acceleration amplification effectively. The axial force time histories are decomposed into a baseline part and a vibration part in this study. The baseline part of axial force well revealed the seismic slope stability, the peak vibration values of axial force of the anchor cables changed significantly in different area of the slope under seismic excitations. The peak lateral earth pressure acting on the back of the anti-sliding pile located at the slope toe was much larger than that acting on the back of the anti-sliding pile located at the slope waist. The test results indicate an obvious load sharing ratio difference between these two anti-slide piles, the load sharing ratio between the two anti-sliding piles located at the slope toe and the slope waist varied mainly in a range of 2-5. The anti-slide pile at the slope waist suppressed the horizontal displacement of the slope surface.
文摘The Three Gorges Project is one of the essential key projects for flood controlling and water resources regulation in the Yangtze River. The project includes a river-crossing dam, underground powerhouses, and navigation structures. Because of the huge size and complicated construction technologies, the project faced a series of challenging engineering issues. In terms of rock mechanics, there are many key technical issues, including the sliding resistance and stability of the dam section along the foundations of powerhouses No.l-5, the ,,;lope stability of the double-line five-stage shiplock, excavation of large-scale underground powerhouses, and curtain grouting under the dam. With decades of scientific research and 16 years of practical construction experiences and reservoir operations, these key technical issues in construction of the Three Gorges Project are successfully resolved, which will attribute to the development of hydropower technology. On the basis of the monitoring data during construction and normal operation periods of the Three Gorges Project, this paper presents a systematic analysis of these key rock mechanical issues in terms of behaviors, solutions, dynamic controlling, monitoring arrangement and integrated assessment.
文摘The stability of a gravity dam against sliding along deep-seated weak planes is a universal and important problem encountered in the construction of dams.There is no recommended method for stability analysis of the dam on deep-seated weak planes under earthquake condition in Chinese design codes.Taking Tingzikou dam as an example,the research in this paper is focused on searching a proper way to evaluate the seismic safety of the dam against sliding along deep-seated weak planes and the probable failure modes of dam on deep-seated weak planes during earthquake.It is concluded that there are two probable failure modes of the dam along the main weak geological planes in the foundation.In the first mode,the concrete tooth under the dam will be cut and then the dam together with part foundation will slide along the muddy layer;in the second mode,the dam together with part foundation will glide along the path consist of the weak rock layer under the tooth and the muddy layer downstream the tooth.While there is no geological structure planes to form the second slip surface,the intersection of the main and the second slip surface is 40 to 80 m downstream from dam toe,and the angle between the second slip surface and the horizontal plane probably be 25 to 45 degrees.
