CAJ | 학술논문

锦屏一级水电站是我国在建的世界最高拱坝,坝肩工程边坡高度达500 m,规模巨大.电站枢纽区地处深山峡谷地区,自然谷坡高陡,地应力水平较高,谷坡岩体卸荷强烈,并发育有断层、层间挤压带、深部裂缝等不良地质现象.在地质条件详细调查基础上,分析左岸缆机平台以上的顺坡向倾倒变形体、左岸1 800 m高程以上的楔形双滑变形拉裂体等坡体结构及其破坏模式,并进行边坡稳定性分区和计算分析.根据坡体结构特点,确定少开挖、弱爆破、强支护、分区分层支护、控制整体、以面覆点的开挖施工和加固设计原则,实施以预应力锚索和抗剪洞为主、辅以锚杆、混凝土框格梁等措施的局部和整体、浅表和深层的全方位、多层次边坡加固控制体系.精细设计并严格控制施工时序、爆破技术和工艺,保证建基面岩体质量,通过动态设计和完善的管理机制确保边坡施工安全.2006年7月～2009年9月边坡监测资料表明:边坡浅表最大横向位移79.5 mm,最大垂直下沉位移52.5 mm,主要受地层岩性和坡体结构控制;深层最大变形量60 mm,最大速率0.1 mm/d,主要受深部裂缝控制;目前位移均趋于收敛,满足安全控制标准.锦屏一级水电站坝肩高边坡工程的成功实施为我国工程建设提供新的经验和借鉴.
금병일급수전참시아국재건적세계최고공패,패견공정변파고도체500 m,규모거대.전참추뉴구지처심산협곡지구,자연곡파고두,지응력수평교고,곡파암체사하강렬,병발육유단층、층간제압대、심부렬봉등불량지질현상.재지질조건상세조사기출상,분석좌안람궤평태이상적순파향경도변형체、좌안1 800 m고정이상적설형쌍활변형랍렬체등파체결구급기파배모식,병진행변파은정성분구화계산분석.근거파체결구특점,학정소개알、약폭파、강지호、분구분층지호、공제정체、이면복점적개알시공화가고설계원칙,실시이예응력묘색화항전동위주、보이묘간、혼응토광격량등조시적국부화정체、천표화심층적전방위、다층차변파가고공제체계.정세설계병엄격공제시공시서、폭파기술화공예,보증건기면암체질량,통과동태설계화완선적관리궤제학보변파시공안전.2006년7월～2009년9월변파감측자료표명:변파천표최대횡향위이79.5 mm,최대수직하침위이52.5 mm,주요수지층암성화파체결구공제;심층최대변형량60 mm,최대속솔0.1 mm/d,주요수심부렬봉공제;목전위이균추우수렴,만족안전공제표준.금병일급수전참패견고변파공정적성공실시위아국공정건설제공신적경험화차감.
The arch dam in Jinping I hydropower station is the highest arch dam under construction in the world;the height of excavated slopes at abutments is over 500 m. The power station is located in high mountains and narrow canyons in Southwest China,where natural slopes are very high and steep with high geostress,intensive rock mass unloading,developed faults,interlayer compressive belts and deep unloading fissures. Based on detailed geological investigation,models of the slope structure and the corresponding failure mode are determined,such as tensile rip rock body at left bank above elevation 1 800 m;zoning and analysis of slope stability are also implemented. According to the characteristics of slope structure,the excavation and harnessing principles are determined as follows:little excavation,slight blasting and strong reinforcement,reinforcing each zone and layer respectively,holistic control and covering local weak points with global measures,local and global,implementing shallow and deep reinforcement controlling systems of slope with prestressed cables and shearing-resistance tunnels as main measures and bolts and concrete grids as complement. Time sequence of construction and blasting technique are precisely designed and firmly controlled to guarantee the quality of excavated rock mass;and dynamic design schemes and reasonable management rules are implemented to ensure the safety of construction. Monitoring data from July 2006 to September 2009 indicate that maximum displacement in surface part of the slope is 79.5 mm,in direction perpendicular to the river;and maximum deformation in deep unloading fissures is 60 mm with the maximum rate of 0.1 mm/d. The displacement tends to converge;and it meets the designed safety standards. The successful implementation of high slopes in Jinping I hydropower station provides new practical experience and reference for future construction of projects,and it indicates a new stage of the research and design of rock mechanics and engineering in China.