Compared with rock roof roadways, coal roof roadways are more sensitive to changes in the stress field due to excavation and mining. For thick-coal-roof roadways, the roof damage range usually exceeds the length of roof bolts, which brings security risks to roadway support. Taking the thick-coal-roof roadways as the study subject, the failure evolution of a thick coal roof under inefficient support was studied for two important geological conditions, namely the gob effect and variation in the coal roof thickness. The field investigation and numerical simulation were performed. The results showed three severely damaged areas from shallow to deep in the thick coal roof, namely a lower area, upper middle area, and coal-rock interface area. The failure of lower coal roof directly affected the stability of the entire thick coal roof. The residual abutment stress of adjacent gob aggravated damage to the lower coal roof. Roof subsidence and damaged area obviously increase with the thickening of coal roof. A critical failure height in the thick coal roof is found. An improved support was proposed adopting a thick anchorage structure and roof surface reinforcement for thick-coal-roof roadways. A field test showed that the coal roof surface of the roadway remained smooth and intact during excavation and mining period. The deformation of the roadway in mining period was reduced by 50%. The damage height of the thick coal roof was also reduced.

与岩石顶板巷道相比，煤顶板巷道对开挖和开采引起的应力场变化更为敏感。对于厚煤顶巷道，顶板损伤范围通常超过顶板螺栓长度，给巷道支护带来安全隐患。以厚煤顶巷道为研究对象，针对采空区效应和煤顶板厚度变化两个重要地质条件，研究了低效支护下厚煤顶板破坏演化规律。进行了实地调查和数值模拟。结果表明，厚煤顶由浅到深三个严重破坏区，即下部区、中上部区和煤岩界面区。下煤顶板的破坏直接影响到整个厚煤顶板的稳定性。相邻采空区的残余邻接应力加剧了下煤顶板的破坏。随着煤顶板的加厚，顶板下陷和破坏面积明显增加。发现了厚煤顶的临界破坏高度。针对厚煤顶巷道，提出了一种采用厚锚固结构和顶面加固的改进支护方案。现场试验表明，在开挖和开采期间，巷道煤顶面保持平整完好。开采期巷道变形减少50%。厚煤顶的破坏高度也降低了。针对厚煤顶巷道，提出了一种采用厚锚固结构和顶面加固的改进支护方案。现场试验表明，在开挖和开采期间，巷道煤顶面保持平整完好。开采期巷道变形减少50%。厚煤顶的破坏高度也降低了。针对厚煤顶巷道，提出了一种采用厚锚固结构和顶面加固的改进支护方案。现场试验表明，在开挖和开采期间，巷道煤顶面保持平整完好。开采期巷道变形减少50%。厚煤顶的破坏高度也降低了。