浅议杭州地铁隧道有害气体的危害及防治对策

Discussion on the Harm of Harmful Gases of Hangzhou Tunnel and Its Countermeasures

研究目的:杭州地铁1号线Ⅰ标段滨康路站至西兴站区间含有沼气层,沼气(瓦斯)在隧道里的聚集将直接危胁到盾构施工和建成后运营安全,可能的瓦斯爆炸甚至会危及地上建筑物和周边的居民。通过室内模拟实验与分析和现场足尺试验测定,提出临界影响值和预防措施。研究结论:通过分析地下工程有害气体对施工及环境的危害程度,拟定了针对土层中有害气体需进行的安全评估内容。以杭州地铁工程为例,研究确定了沼气排放的解决方法,通过室内模拟实验和现场足尺试验测定沼气浓度对施工和运营的临界影响值,并采用在地面上打一定数量的排气孔,将富涵在地下浅层中的沼气排出,降低或消除沼气引起的安全隐患,确保了地铁施工和运营期的安全。

Research purposes： Marsh gas exists in the area from Binkang Road Station to Westxing Station of Line 1 of Hangzhou subway.If the marsh gas gathers in the tunnel,it＇ll cause harms to the construction of shield tunnel and the operation safety of the tunnel,and even the probable gas blast can cause the harms to the surrounding residents and buildings.Based on indoor simulation experiment and analysis as well as the full-scale experiment,the critical influence values and preventive measures are presented.Research conclusions：Through analyzing the harmful degree of harmful gas on the underground construction and environment,the security assessment contents necessarily done to the harmful gas contained in soil is are worked out.For construction of Hangzhou subway,the study is done on the solution to emission of the marsh gas.By doing the indoor simulation experiment and field full-scale experiment,the critical influence values of the marsh gas on the construction and operation of tunnel are obtained.In addition,it is necessary to drill some holes into ground to emit the marsh gas contained in shallow soil for reducing or eliminating the hidden safety danger so as to ensure the safety of the tunnel construction and operation.