摘要
TB水电站河床坝段基坑面积广,开挖工程量大。坝基岩性单一,均为辉长岩,其弱风化、微风化岩石饱和抗压强度平均值高,属坚硬岩。基坑水平建基面开挖前,针对施工条件及岩性特点进行了复合消能现场试验。通过平整度检测、爆破振动测试以及爆破损伤程度检测数据分析,验证了建基面开挖采用复合消能爆破的可行性并确定了爆破开挖参数。该坝基开挖采用复合消能爆破技术,既保证了建基面开挖质量,也大大缩短了开挖工期,为大坝基础垫层混凝土如期浇筑提供了良好条件。
The area of the foundation pit of the riverbed dam section of TB Hydropower Station is big and the amount of excavation is large. The dam foundation is of a single rock type of gabbro, which is a hard rock as the average saturated compressive strengths of the weakly weathered and slightly weathered rock are rather high. Before the excavation of the horizontal foundation surface of the foundation pit, in-situ tests of the shock-reflection blasting are carried out considering the construction conditions and the lithologic characteristics. The feasibility of the shock-reflection blasting technique in the foundation excavation construction is verified with the analysis of the flatness tests, blasting vibration tests and the blasting damage tests. Also, the blasting excavation parameters are determined. Practice shows that the application of the shock-reflection blasting technique in the dam foundation excavation not only ensures the excavation quality of the foundation surface, but also greatly shortens the construction period, which provides favorable conditions for the on-schedule pouring of the dam foundation cushion concrete.
作者
赵银超
Zhao Yinchao(Sinohydro Bureau 8 Co.,Ltd.,Changsha 410004,China)
出处
《水电与新能源》
2022年第11期8-13,共6页
Hydropower and New Energy
基金
国家自然科学基金资助项目(编号:50809052)。
关键词
水利工程
辉长岩
基坑开挖
复合消能爆破
water conservancy project
gabbro
foundation pit excavation
shock-reflection blasting technique
