机场填方高边坡稳定性设计计算理论及算法分析

Design Calculation Theory and Algorithm Analysis for the Stability of High-Fill Slopes in Airport Earthworks

目前许多机场的选址被迫在山地、丘陵等远离平原的地区。为了满足机场对平坦地形地势的要求会导致大量的土石方挖掘和填方高边坡的形成,这类边坡具有地质条件复杂,高度大,形成时间短的属性,其稳定性严重制约和影响着机场的设计、建设和运营。本论文的研究依托某机场填方高边坡工程和现场调研得到的数据,计算在不同填方高度下的地基基顶的压力值,并计算出地基沉降数值,均小于1 m,以此作为边坡稳定性分析的前提条件。然后开展边坡稳定性分析,通过对某机场填方高边坡工程进行现场调研,得到边坡相关数据。根据病害形成机理和研究区高边坡现状提出了影响边坡稳定性的影响因素,并对其进行边坡稳定性计算分析。论证不同填方高度、不同坡率、不同回填土下的边坡稳定性并进行敏感性分析得到:随着高边坡填方高度的增加,边坡稳定性逐渐变差,边坡稳定安全系数逐渐减小并趋于1.50;随着高边坡坡率增加,边坡坡体变得越倾斜,边坡稳定性变差,坡率在1:2.5、1:2.75、1:3.0时的稳定安全系数均大于1.30;中风化石料与块状填石作为回填土时,稳定安全系数均大于1.30,满足评价指标,边坡稳定性较好。

In recent years,due to the limited availability of flat terrain,many airports have been forced to be located in mountainous and hilly areas.To meet the requirements for flat terrain,substantial earthworks involving excavation and high-fill embankments are often necessary.These embank-ments are characterized by complex geological conditions,significant height,and short formation periods,which severely impact the design,construction,and operation of airports.This study,based on a high-fill embankment project at a particular airport and data obtained from field sur-veys,calculates the pressure values at the foundation top under different fill heights and deter-mines the foundation settlement values,all of which are less than 1 meter.These calculations serve as the preliminary conditions for slope stability analysis.Subsequently,a slope stability analysis is conducted.Field surveys of the airport’s high-fill embankment project provide data on slope gradient,slope height,and rock-soil layers.The study identifies factors influencing slope stability based on the mechanisms of damage formation and the current state of the high-fill em-bankments in the study area.Stability calculations are then performed to evaluate the slope stability under different fill heights,gradients,and types of backfill material.Sensitivity analysis reveals that as the fill height of the high embankment increases,slope stability deteriorates,with the stability safety factor gradually decreasing towards 1.50;as the slope gradient increases,making the slope steeper,stability decreases;the safety factor exceeds 1.30 for gradients of 1:2.5,1:2.75,and 1:3.0;when using moderately weathered rock and blocky fill as backfill materials,the stability safety factor exceeds 1.30,meeting evaluation criteria and indicating relatively good slope stability.