“广蓄”电站地下厂房岩壁吊车梁施工

Construction of rock abuttal for bridge crane in an underground pumped storage power plant

广州抽水蓄能电站(广蓄)地下厂房,全长146.5米,高44.54米,宽22米,是我国规模较大的水电站地下厂房。厂房位于黑云母花岗岩体内,岩性坚硬。由于岩壁吊车梁具有缩窄厂房开挖宽度,自上而下分层开挖,缩短地下厂房施工工期,吊车梁受力明确,结构安全,便于施工等优点。经比较采用了岩壁吊车梁方案.岩壁采用光面爆破.控制振松范围不大于20厘米,岩台倾角不小于20°(±3°),对不稳定岩体采用随机锚杆加固,处理 F_(7012)断层蚀变带,采用浅层挖除、回填混凝土塞、浅层锚杆补强措施。混凝土采用二级配 R=200~#浇筑,单位水泥用量330公斤/立方米。根据施工质量追踪,以及观测监测表明:施工质量好,获1991年度能源部优质工程单项奖。

The underground power—plant of Guangzhou pumped—storage hydropower station.witha length of 146.5m,width of 44.54m,height of 22m,is a large—scale one of its kind in China.Thefoundation is hard biotite—granite.After alternative comparison,rock crane abuttal on side wall wereadopted as they have such advantages as of less excavation width of plant,convenient successive excava-tion by layers from top to bottom,shortening of construction period,simplicity of stress analysis,struc-tural reliability and easiness for construction.Rock side walls were formed by means of smooth surfaceblasting with affected loosing fringe ranging less than 20 cm and desirable angle of inclination of the rockberm.Unstable blocks of rock mass were anchoraged and reinforced by bolts.For F_(?)fault affectedzone,weak rock was excavated in the form of a shallow trough and back filled with bolt—anchored con-crete plug.Two grade aggregates R200# concrete was used with a cement content of 330kg/m^3.Thesubsequent inspection and observation revealed that the rock abuttal construction quality is excellent,and it was awarded a specific prize by Ministry of Energy in 1991.