To study the performance of smoke control in tunnels with roof openings under the conditions of natural ventilation and various combinations of shaft parameters, a series of orthogonal experiments were conducted. Taking the shaft width, height, group space and the number of the shaft as the controllable factors and the maximum smoke temperature under the tunnel ceiling, smoke diffusion rate and smoke sedimentation rate as the evaluation index, some optimized schemes, which aim at lowering the maximum smoke temperature under the tunnel ceiling and re-ducing the smoking diffusion rate and smoke sedimentation rate, were obtained. The results show that the tempera-ture around the tunnel ceiling is lower than 100℃in each case;the shaft width has the largest influence on the maxi-mum smoke temperature around the ceiling;the shaft height has a large influence on both the smoke diffusion rate and the smoke sedimentation rate;and the shaft group space affects the smoke diffusion rate significantly.%为了研究竖井不同尺寸参数组合变化时,自然通风半敞开式隧道发生火灾时的防排烟性能,文章设计并开展了一系列小尺寸模型试验,选取竖井宽度、高度、组间距以及每组竖井数量作为可控因子,选择顶棚附近最高烟气温度、烟气扩散速率和烟气沉降速率作为考核指标,分别得到了降低顶棚附近最高烟气温度、减小烟气蔓延速率和烟气沉降速率的竖井优化方案.研究结果表明,各工况顶棚附近最高烟气温度均小于100℃,竖井宽度对顶棚附近最高烟气温度影响最大,而竖井高度对烟气扩散速率和烟气沉降速率影响均比较大,竖井组间距对烟气扩散速率影响显著.
展开▼
