挂板式斜插桩板墙结构的桩间土拱效应分析

为研究不同桩间距变化对挂板式斜插式桩板墙受力机理的影响,采用ABAQUS有限元软件对5组不同桩间距下的挂板式斜插桩板墙模型墙后土压力、结构受力、桩间土拱效应、土拱强度随深度的变化趋势等进行了模拟分析。结果表明:由于挡土板倾斜和桩间土拱效应等的影响,挂板式斜插桩板墙墙后土压力分布模式与传统朗肯土压力明显不同,具体表现为桩后土压力大于朗肯主动土压力、斜插板后土压力小于朗肯主动土压力,呈锯齿状变化;斜插桩板墙桩结构受力随悬臂段增加迅速递增,板结构受力随悬臂段先增加后减小,随桩间净距加大,斜插板结构受力增加速度远大于桩。此外,土拱强度随悬臂深度的增加先增大后迅速减小,随桩间净距的增大整体上呈现减弱趋势。为尽可能充分利用土拱作用,建议合理桩间净距取3~4倍桩截面宽度。

An Analysis of Soil Arch Effect between Piles on Slanting Pile Wall Structure

In order to study the effect of different pile spacing on the stress mechanism of slanting pile-wall with hanging plate,ABAQUS finite element software was used to calculate the soil pressure behind the model wall of 5 groups of slab-mounted slanting pile with different pile spacing,structural stress,soil arch effect between piles,the variation trend of soil arch strength with depth is simulated.The results show that because of the influence of retaining plate tilt and soil arch effect between piles,the distribution model of soil pressure behind slanting pile-wall is different from that of traditional Rankine soil pressure,the soil pressure behind the pile is greater than that of Rankine active soil pressure,the soil pressure behind the inclined planking is less than that of Rankine active soil pressure,showing serrated changes;With the increase of the cantilever section,the stress of slanting pile increases rapidly,the force of plate structure decreases with the increase of cantilever section,as the net distance between piles increases,the increasing speed of force on the structure of inclined insert plate is much faster than that of pile.In addition,the strength of soil arch increases first and then decreases rapidly with the increase of cantilever depth,with the increase of net distance between piles,the overall has a trend of weakening.To make the best use of the earth arch,it is suggested to take 3~4 times the width of pile cross section for a reasonable net distance between piles.