上覆堆载作用下砂性地层埋入式筒仓浮力分析

Buoyancy Analysis for Buried Silo in Sandy Stratum Under Overlying Surcharge Load

河南是国家粮食三大主产区之一,实现粮食大规模的绿色储粮利国利民,地下/半地下粮仓具有储量大、低温等优点是绿色储粮的理想仓型之一,但地下大体积结构抗浮设计问题突出。以入地式筒仓为研究对象,考虑仓周上覆堆载开展模型试验和理论研究,理论反演分析筒仓上浮时的临界状态对应的浮力折减系数。研究表明:随着筒仓周边施加的均布荷载不断增加,仓壁受土体侧摩阻力也逐渐增加,抑制仓体上浮;浮力在土体中存在着一定的折减。在饱和粗砂土质中,浮力折减系数估算为0.945;增加上覆荷载可以提升筒体埋深的设计潜力,为低温、绿色储粮提供更大可能。

Henan is one of the three major grain producing areas in China,and the realization of large-scale green grain storage is beneficial to the country and the people.The underground or semi-underground grain storage has the advantages of large reserves and low temperature,which is one of the ideal types of green grain storage,but the anti-floating design of underground massive structure is prominent.This study focuses on the buried cylindrical silo as the research object,conducts model experiments and theoretical research with considering the overlying load around the silo,and analyze the buoyancy reduction coefficient corresponding to the critical state of the silo floating by theoretical inversion.The research indicates that as the uniformly distributed load around the silo continues to increase,the lateral friction resistance of the silo wall to the soil also gradually increases,which inhibitis the upward flotation of the silo.Additionally,there is a certain reduction of buoyancy in soil.In saturated coarse sand,the estimated buoyancy reduction coefficient is 0.945.Increasing the overlying load can enhance the design potential of the buried depth of silo and provide greater possibilities for low-temperature and green grain storage.