成贵铁路四川红层段瓦斯特征分析及勘察阶段划分隧道瓦斯工区类别的建议

Analysis on Gas Characteristics of the Sichuan Red-bed Section of ChengduGuiyang Railway and Suggestion on Division of Gas Working Areas in the Survey Stage

结合成贵铁路四川红层段钻孔瓦斯浓度测试,在数据统计的基础上分析其与地层年代、地质构造、隧道埋深的相关性,并提出定性、定量划分瓦斯工区类别的建议。结果表明,成贵铁路四川红层段(含煤地层除外)隧道瓦斯浓度与地层年代相关性不明显,地质构造对瓦斯运移、积聚起控制性作用,隧道瓦斯浓度与埋深正相关性明显。根据以上结论在勘察阶段结合地质构造及收集的调绘资料对瓦斯工区可做定性划分,根据瓦斯浓度测试结果可做瓦斯工区定量划分,定性与定量相结合最终确定瓦斯工区类别。

Combining with the borehole gas concentration tests for the Sichuan red-bed section of the Chengdu-Guiyang Railway, this paper analyzes its correlation with the stratum chronology geological structure, and tunnel depth on the basis of data statistics, and puts forward the suggestion to qualitatively and quantitatively divide gas working areas. The results show that the correlation between the tunnel gas concentration and the stratum chronology is not significant in the Sichuan red-bed section of the Chengdu-Guiyang Railway(except coal-bearing strata);geological structure plays a controlling role in gas transport and accumulation;and the positive correlation between the gas concentration and the tunnel depth is significant. According to the above conclusions, it could qualitatively divide the gas working areas according to the geological structure and mapping information collected during the survey stage,and quantitatively divide the gas working areas according to the gas concentration test results. The final categorization of gas working areas can be determined by combining the qualitative and quantitative results.