红粘土的大气张力郎肯土压力

Atmospheric Tension Rankine's Earth Pressure of the Red Clay

本文总结了红粘土的大气张力郎肯土压力算法。其计算要点有,红粘土的实际饱和度、饱和度系数、自由水通道率、膜的抗剪强度贡献、大气张力郎肯土压力。"大气"指按绝对压强计算,"张力"指要素中含有收缩膜的表面张力。算例分析表明,按经典郎肯土压力,"上硬下软"的红粘土基坑上部主动土压力为负值,表示土体拉住支护,处理为零,这是错误的;而按大气张力郎肯土压力,表示坑内支护上的大气压强能抵抗主动土压力,扶住支护。分析还表明,这种基坑或边坡支护,采用土钉墙、加筋水泥土桩墙+锚杆(索),深基坑及高边坡采用框架格梁+锚杆(索),比较经济实用;但应注意基坑或边坡底应局部加强,以满足边坡稳定的要求。

In this paper,the algorithm of the atmospheric tension Rankine＇s earth pressure of red clay is summarized. The actual saturation of the red clay,the saturation coefficient,the rate of free water channel,the shear strength of membrane contribution,atmospheric tension Rankine＇s earth pressure are the calculation values. Refers to the atmosphere in absolute pressure calculation and the tension that the elements contained in contraction membrane surface tension. Calculation example analysis shows that,according to the classic Rankine＇s earth pressure,for the red clay foundation pit is ＂hard in top soft in low＂,the upper active earth pressure is negative,that is wrong to say the soil pull in support and the handle is zero. And according to the atmospheric tension Rankine＇s earth pressure,the atmospheric pressure on the pit supporting can resist active earth pressure and hold support. The analysis also shows that,this kind of foundation pit or slope support use soil nail wall,reinforced cement-soil pile wall ＋ anchor rod（ rope）,deep foundation pit and high slope can use frame beam ＋ anchor rod（ rope） can be more economical and practical. But attention should be paid to the bottom of the foundation pit or slope should be local strengthening if it can meet the requirements of the slope stability.