三峡导流明渠截流施工技术

三峡导流明渠截流具有水力学指标高、施工时间短、抛投强度大、分流条件较差和通航与施工干扰等特点.导流明渠截流设计流量为10 300 m3/s,相应截流总落差4.11 m,实际截流流量基本稳定在8 600 m3/s左右,总落差为2.5 m.采用明渠双戗堤立堵截流,需要研究解决龙口段施工技术、上下游戗堤进占相互配合、设置拦石坎和提高抛投强度、防止堤头塌滑等问题.由于施工保证措施,施工技术,施工组织得当,加上有利的水情和条件,导流明渠截流圆满成功.

River closure construction technology of TGP open diversion channel

The closure of the open diversion channel of the Three Gorges Project was characterized by its high hydraulic index, short construction time, great dumping intensity, poor flow diversion condition and some interference between navigation and project construction. The design discharge for the closure of the open diversion channel was 10 300 m\+3/s and the corresponding total drop was 4.11 m, while the actual discharge at the Three Gorges Project was about 8 600 m\+3/s, its corresponding total drop was about 2.5 m. The realization of the open diversion channel's vertical closure by double closure dykes need study and solve a series of problems: such as the construction technology for the closure gap section, the coordinated progression of the upstream and downstream closure dykes, the setting up of suitable stone-intercepting sill, the increasing of dumpimg intensity and the collapse prevention of the closure dyke nose. Since the construction-guaranteing measures, construction technology and construction organization were all suitable, and the water regime and flow condition were favorable, the river closure of the open channel achieved complete success.