论文部分内容阅读
盾构施工会对周围土体产生扰动,形成超孔隙水压力,引起工后固结沉降。运用应力释放理论推导与衬砌相邻的土体初始超孔隙水压力计算公式。假定扰动范围边界呈圆弧状,确定初始超孔隙水压力的分布范围;同时运用应力传递理论,推导分布范围内任一点土体的初始超孔隙水压力计算公式。通过对实测资料的分析可知,计算值与实测值吻合较好。算例分析表明,与衬砌相邻的土体初始超孔隙水压力呈近似圆形(顶部小、底部大);随着到衬砌的径向距离增加,土体初始超孔隙水压力呈凹曲线形状;隧道底部的等值线最密,即变化最快;隧道顶部上方土体、不同深度处土体初始超孔隙水压力,以隧道轴线处为最大,呈现类似Peck曲线形状。
Shield construction will disturb the surrounding soil, forming excess pore water pressure, causing post-construction consolidation settlement. The stress release theory was used to deduce the formula of the initial excess pore water pressure of the soil adjacent to the lining. Assuming that the boundary of the disturbance range is arc-shaped, the distribution range of the initial excess pore water pressure is determined. At the same time, the initial excess pore water pressure formula of soil at any point in the distribution range is deduced using the stress transfer theory. Through the analysis of measured data shows that the calculated value is in good agreement with the measured value. The case study shows that the initial excess pore water pressure of the soil adjacent to the lining is approximately circular (small top and large bottom). The initial excess pore water pressure of the soil is concavely curved with the increase of the radial distance to the lining ; The contour at the bottom of the tunnel is the most dense, that is, changes most rapidly; the initial excess pore water pressure of the soil above the top of the tunnel at different depths is the largest at the axis of the tunnel, showing a Peck-like curve shape.