The conventional design criterion of the safety factor for pillar stability is a deterministic approach characterised by non-random and exact values of its input parameters i.e. strength and stress. The integrity of pillars often jeopardized when some fluctuations or deviations occur in their strength and stress due to uncertainties in field conditions. To counter these unknown fluctuations or deviations, the coal pillars are designed with safety factors greater than unity and their exact values are selected based on local geomining factors. This practice does not guarantee stability against the geomining uncertainties and consequently lock-up the coal in the bigger size of the pillars. Therefore, to assess the variability in the input parameters in pillar design, this paper presents a probabilistic approach to analyse the stability of coal pillars considering the cases of stable and failed pillars in Indian coalfields. The databases of input design parameters are collected for stable and failed coal pillars from different Indian coal mines. The probabilistic distribution fittings of strengths, stresses and safety factors of stable flat, stable inclined, failed flat and failed inclined pillar cases are derived to know their means and standard deviations. The Monte Carlo Simulation and the First Order Reliability Method have been implemented to solve the limit state functions. The failure probabilities estimated for stable flat, stable inclined, failed flat and failed inclined cases are 0.29, 0.28, 0.56, and 0.99 respectively. The analysis recommends the safety factors of corresponding threshold failure probabilities of stable flat pillars as 1.61 and for stable inclined pillars as 1.41 in Indian mines with the ranges of design parameters considered in their databases. Therefore, the probabilistic stability analysis can provide an additional design criterion to select the optimum safety factor of pillars for improved recovery rates in coal mines.

支柱稳定性安全系数的常规设计标准是一种确定性方法，其特征在于其输入参数（即强度和应力）的非随机和精确值。由于现场条件的不确定性，当支柱的强度和应力出现一些波动或偏差时，支柱的完整性往往会受到威胁。为了应对这些未知的波动或偏差，煤柱的安全系数设计为大于 1，并根据当地地质挖掘因素选择其准确值。这种做法不能保证对地质开采不确定性的稳定性，从而将煤炭锁定在更大尺寸的支柱中。因此，为了评估支柱设计中输入参数的可变性，本文提出了一种概率方法考虑印度煤田稳定和失效煤柱的情况，分析煤柱的稳定性。输入设计参数的数据库是为来自不同印度煤矿的稳定和失效煤柱收集的。推导出稳定平面、稳定倾斜、失效平面和失效斜柱案例的强度、应力和安全系数的概率分布拟合，以了解它们的均值和标准偏差。已经实施了蒙特卡罗模拟和一阶可靠性方法来解决限制状态函数。对于稳定的平坦、稳定的倾斜、失败的平坦和失败的倾斜情况，估计的失败概率分别为 0.29、0.28、0.56 和 0.99。分析建议印度矿山稳定平柱相应阈值失效概率为1.61，稳定斜柱安全系数为1.41，设计参数范围在其数据库中考虑。因此，概率稳定性分析可以提供额外的设计准则来选择支柱的最佳安全系数以提高煤矿的采收率。