根据关键层理论建立了沿空留巷巷道直接顶弹性力学模型，通过位移变分法推导了隔离墙下沉量与支撑阻力之间的数学表达式，发现两者之间满足线性关系，得出了沿空留巷巷道顶板下沉存在“给定变形”的特点，并给出了变形量的计算公式。研究发现沿空留巷隔离墙的主要作用不是强制抵挡巷道顶板下沉，而是维护顶板稳定，通过提高隔离墙承载能力来强制控制顶板下沉的作用不明显。 利用计算机数值模拟软件分析了不同接顶高度下隔离墙与巷道围岩的受力与变形，得出接顶高度存在一个合理范围。合理的接顶高度可以有效改善墙体的侧向变形和墙体下沉，采用混凝土充填隔离墙建议接顶高度选择200~300mm，接顶高度过小时墙体难以适应顶板强制下沉而发生破坏，接顶高度过大又会引起巷道围岩变形较大，且不利于顶板稳定。根据隔离墙让压技术要点，提出采用预支撑混凝土隔离墙可以改善隔离墙力学性能，使巷道顶板支撑荷载由柱体向墙体平滑过渡，避免顶板在墙体形成有效支撑能力之前将墙体压坏。 基于隔离墙让压要点对传统沿空留巷技术进行了优化，将优化后的沿空留巷技术实践到乌兰煤矿5868运输巷道，通过矿压监测数据分析，将隔离墙下沉量与巷旁支护阻力随回采工作面推进划分成三个阶段，即隔离墙快速下沉阶段、隔离墙支撑阻力过渡阶段和隔离墙承载阶段。提出让压隔离墙对维护沿空留巷巷道围岩稳定起到的作用非常显著，为矿山沿空留巷提供了可靠的理论依据与技术指标。

The elastic mechanics model of gob-side entry retaining’s immediate roof is established based on critical layer theory, and the arithmetic expressions between subsidence and support resistance of separation wall is deduced by the displacement variational method, and their linear relations is discovered as well. Moreover, it is concluded that the subsidence of roadway roof of gob-side entry retaining is given deformed and calculation expression of deformation is available in this thesis. This thesis points out that the main function of gob-side entry retaining’s separation wall is to maintain the stability of roadway roof, not to resist the subsidence of it. This thesis also points out that there will have no obvious effect to have a forcible control of roof’s subsidence by increasing loading capacity of separation wall. The stress and deformation of the separation wall and roadway’ surrounding rock in different roof contact height is analyzed by numerical simulation software, and it is concluded that there exists a reasonable value for the roof contact height, which can improve the separation wall’s lateral deformation and subsidence effectively. 200mm to 300mm of roof contact height is suggested if using filling concrete separation wall. A too low roof contact height will damage the separation wall for the reason that the forcible subsidence of roadway roof is difficult to support, while a too tall roof contact height will cause a larger deformation of roadway’s surrounding rock and go against with roof’s stability. Based on key points of yielding technology of separation wall, this thesis puts forward that pre-supporting concrete separation wall can improve the separation wall’s mechanical property, which makes a smooth transition of roadway roof’s supporting loading from pillar to wall, and avoids roof’s damaging of the separation wall before the wall can support effectively. The traditional gob-side entry retaining technology is optimized based on the key points of separation wall’s yielding technology. After carrying the optimized gob-side entry retaining technology out to Wulan coal mine 5868’s haulage roadway, it is discovered, by mine pressure monitoring data, that with the proceeding of stope face, the subsidence of separation wall and roadway-side’ support resistance can be divided into 3 phrases, which is the rapid subsidence phrase of the separation wall; the transitional phrase of separation wall’s support resistance and the loading phrase of the separation wall. The thesis puts forward that the separation wall with yield pressure has a very obvious effect in maintaining roadway’s surrounding rock’s stability in gob-side entry retaining, which provides reliable theoretical foundation and technical index for gob-side entry retaining in coal mine.