摘要
为快速恢复南昌红谷隧道冬汛灾后被冲毁的模袋砂堰体,给围堰内剩余工程提供无水作业条件,选用"土石围堰+塑性混凝土钻孔咬合桩和高压旋喷桩防渗体系"新型堰体恢复方案:水中利用抓斗船沿围堰轴线抛填石块,陆上利用自卸汽车外运黏土从堰体两端逐步抛填直至堰体合拢,采用成孔过程中对周边地层扰动较小的反循环钻机施工塑性混凝土钻孔咬合桩,并在新做塑性混凝土咬合桩与原围堰塑性混凝土防渗墙接茬处施工高压旋喷桩加强止水。实践证明:重建土石围堰具有施工速度快、成本相对较低、作业区域小、稳定性好、抗渗能力强等优点,适用于沉管隧道江中围堰的新建和重建等临时性水利工程。
The sandbag cofferdam of Honggu Tunnel in Ganjiang River was destroyed by winter season. It has to be reconstructed so as to provide waterless working conditions for further construction. New construction scheme of ＂earth- rock cofferdam ＋ plastic concrete bored secant pile and high pressure jet grouting pile seepage prevention system＂ is adopted. The scheme includes, rock filling along axial line of cofferdam by grab dredger, rock pushing towards cofferdam by dump truck, using plastic concrete bored secant pile constructed by reverse circulation drill and high pressure jet grouting pile seepage prevention system. The construction practice shows that the reconstructed earth-rock cofferdam has advantages of rapid construction, low cost, small operating area, stable and impermeable; so that it can be applied to new and reconstructed temporary hydraulic engineering works.
出处
《隧道建设》
北大核心
2016年第9期1114-1119,共6页
Tunnel Construction
关键词
沉管隧道
模袋砂围堰
土石围堰
围堰重建
塑性混凝土钻孔咬合桩
immersed tunnel
sandbag cofferdam
earth-rock cofferdam
reconstructed cofferdam
plastic concrete boredsecant pile
