In the construction of long-span sea crossing bridge, it is often necessary to build huge pier foundation in deep water, which often uses steel cofferdam to block water, forming dry construction conditions. Under the ...In the construction of long-span sea crossing bridge, it is often necessary to build huge pier foundation in deep water, which often uses steel cofferdam to block water, forming dry construction conditions. Under the condition of silt layer exceeding 40m and deep water, the construction technology of double wall steel cofferdams is adopted for the steel cofferdams of bridge caps. Baiteng river section of Jinhai super large bridge between Zhuhai and Jinan is adjacent to Jinhai highway bridge (Baitenghe bridge). The left and right sections of the highway are located on both sides of the railway. The main pier 129 # - 130 # (corresponding to the left and right sections of the highway) crosses the main channel of Baitenghe river with a span of 180m, and the stratum is mainly composed of two layers. The average thickness of the muddy layer is about 45m, and the highway and railway are adjacent to each other, so it is difficult to construct the cofferdam. According to the construction characteristics of this project, this paper studies the construction technology of steel sheet pile combined cofferdam and underwater concrete bottom sealing.展开更多
In the present study, an analytical solution is presented to solve the problem of combined seepage, under a sheet piling cofferdam, applied to dewatering systems. Existence of the sheet pile creates a confined seepage...In the present study, an analytical solution is presented to solve the problem of combined seepage, under a sheet piling cofferdam, applied to dewatering systems. Existence of the sheet pile creates a confined seepage followed by an unconfined seepage in the same field, which presents a combined seepage problem. Two equations were developed to analyze the combined seepage underneath a sheet piling wall. Using such equations, both the maximum height of the free surface just behind the sheet piling cofferdam (H<sub>o</sub>) and the quantity of seepage discharge to be pumped out from the construction site (q) can be determined. The main parameters affecting the combined seepage characteristics underneath a sheet piling wall are: The depth of permeable foundation layer (T), the horizontal distance behind the sheet pile (X), the depth of excavation in the construction site (D), the embedded depth of sheet pile (S), the retained water head (H<sub>1</sub>), the accumulated seepage water depth (H<sub>2</sub>), and the side slope factor of excavation line (M). Study showed that, the above parameters have a great effect on the combined seepage, but with different extents.展开更多
文摘In the construction of long-span sea crossing bridge, it is often necessary to build huge pier foundation in deep water, which often uses steel cofferdam to block water, forming dry construction conditions. Under the condition of silt layer exceeding 40m and deep water, the construction technology of double wall steel cofferdams is adopted for the steel cofferdams of bridge caps. Baiteng river section of Jinhai super large bridge between Zhuhai and Jinan is adjacent to Jinhai highway bridge (Baitenghe bridge). The left and right sections of the highway are located on both sides of the railway. The main pier 129 # - 130 # (corresponding to the left and right sections of the highway) crosses the main channel of Baitenghe river with a span of 180m, and the stratum is mainly composed of two layers. The average thickness of the muddy layer is about 45m, and the highway and railway are adjacent to each other, so it is difficult to construct the cofferdam. According to the construction characteristics of this project, this paper studies the construction technology of steel sheet pile combined cofferdam and underwater concrete bottom sealing.
文摘In the present study, an analytical solution is presented to solve the problem of combined seepage, under a sheet piling cofferdam, applied to dewatering systems. Existence of the sheet pile creates a confined seepage followed by an unconfined seepage in the same field, which presents a combined seepage problem. Two equations were developed to analyze the combined seepage underneath a sheet piling wall. Using such equations, both the maximum height of the free surface just behind the sheet piling cofferdam (H<sub>o</sub>) and the quantity of seepage discharge to be pumped out from the construction site (q) can be determined. The main parameters affecting the combined seepage characteristics underneath a sheet piling wall are: The depth of permeable foundation layer (T), the horizontal distance behind the sheet pile (X), the depth of excavation in the construction site (D), the embedded depth of sheet pile (S), the retained water head (H<sub>1</sub>), the accumulated seepage water depth (H<sub>2</sub>), and the side slope factor of excavation line (M). Study showed that, the above parameters have a great effect on the combined seepage, but with different extents.
