【作者】 赵红莉；

【导师】 徐志胜；

【作者基本信息】 中南大学 ， 土木工程， 2013， 博士

【摘要】 摘要：我国公路隧道近年来向长大化方向发展,正常运营时污染物在隧道内累积达到较高浓度的可能性和火灾事故的危险性呈上升趋势,公路隧道通风排烟技术是隧道安全运营的重要保障。因此,本文对公路隧道的各种通风排烟方式进行了系统的研究,提出了基于网络模型的公路隧道的通风排烟计算方法,并将研究成果运用于实际工程中,通风排烟网络解算结果得到了火灾模型试验的验证。本论文的研究工作主要包括以下几个方面的内容：(1)在公路隧道通风计算中引入通风网络理论,系统的研究了纵向通风模式、半横向通风模式、横向通风模式和组合通风模式下隧道正常运营通风的风流特点和风压组成,绘制出了各通风系统的通风网络图,建立了公路隧道各种通风模式下的正常营运通风网络解算模型,提出了风机配置方法。(2)建立了公路隧道火灾通风排烟网络解算模型,给出了不同隧道通风排烟模式下主要技术参数、所需风机风量、风压的计算方法。(3)编制了基于质量描述的隧道网络通风模拟计算程序,该程序可完成分支风量、风压、风速、通风阻力、风机数量等参数的求解计算。(4)对集中排烟模式下排烟阀和排烟道所在分支的风阻系数随不同排烟阀设置方案的动态性变化进行了研究。获得了不同排烟阀设置方案下,行车道和排烟道内烟气温度分布、排烟道内和排烟阀处烟气流速分布,确定了分支密度和风阻系数这两个关键参数。(5)将研编的通风网络计算程序应用于苍岭隧道集中排烟模式下火灾通风排烟技术研究。获得了排烟阀设置方案、排烟方式、排烟量和漏风量对排烟道内和排烟阀处烟气流速的影响规律,确定了较好的排烟阀设置方案。最后,采用模型试验方法对火灾通风网络计算结果进行验证,证实了网络程序的可靠性。(6)基于贝叶斯网络的逻辑,建立了通风排烟系统设备正常工作的贝叶斯网络模型,分别获得了通风排烟系统设备正常工作和失效的概率计算公式。通过对隧道通风排烟模式的系统研究,建立了正常营运工况、火灾工况的通风网络解算模型,实现了风量、风压、风速、通风阻力、风机数量等参数的求解,为以后公路隧道通风设计和计算提供了参考。更多还原

【Abstract】 Abstract:In recent years, the road tunnels in China are growing both in length and scale, which makes it more possible for the contamination to accumulate to a high concentration and result in a disaster, and the tunnel ventilation and smoke extraction technology becomes the key guarantee for the tunnel security. So, in this paper, a systematic research on ventilation and smoke extraction modes of tunnel is carried out, and method is proposed based on the network model for calculation and design of tunnel ventilation and smoke exhaust system. And then, it is applied to a practical engineering, and the results calculated by ventilation network model are validated through fire model tests. The main work of the paper are as follows:(1) The ventilation network theory is introduced into the calculation of road tunnel ventilation systems, the flow characteristics and compositions of ventilation power are analyzed respectively under longitudinal ventilation mode, semi-transverse ventilation mode, transverse ventilation mode and combination ventilation mode, network graphs of the tunnel ventilation systems are drawn, and calculation models based on network and how to configure fans in normal operation condition under different tunnel ventilation modes are proposed.(2) Calculation models based on ventilation network in fire operation condition are proposed, and the method for calculating central technical parameters, the air flux and pressure of fans in need under different tunnel fire ventilation modes are provided.(3) A road tunnel ventilation network calculation procedure with the air flux expressed by mass flux is developed. The procedure can realize the calculation of mass flow rate, wind pressure, wind speed, ventilation resistance and number of fans in need.(4) The dynamic variations of wind resistance coefficient attached to smoke vent and smoke duct branches with the different smoke vent design schemes under central exhaust mode are studied in this paper. In different smoke vent design scenarios, the smoke temperature distributions along tunnel ceiling and smoke duct, the smoke flow velocity distributions along the duct and through the vent are acquired. Finally, the two key parameters, wind density and wind resistance coefficient of network branches are determined.(5) The calculation procedure is applied to the research of smoke extraction technology in Cangling tunnel with central exhaust mode, the rule how the smoke vent design schemes, smoke exhaust modes, exhaust volume and air leakage influence the smoke flow velocity distributions along the duct and through the vent is gained, and proper vent design scheme is proposed. In the end, the reliability of the network procedure is approved by comparing the calculation results of procedure in fire operation condition with reduced-scale model fire tests.(6) A bayesian network model is established to reliability analysis of fire ventilation system devices based on bayes theory, and the formulae for calculating the possibility of ventilation system devices in working state and in failure state are provided, respectively.Based on the systematic research of ventilation and smoke extraction modes in tunnel, network models are established for the tunnel ventilation calculation in normal operation condition and in fire operation condition, and the mass flow rate, wind pressure, wind speed, ventilation resistance and number of fans in need can be solved, which has a reference meaning to future road tunnel ventilation system design and calculation.更多还原