Study On Escape And Rescue System Effectiveness Of Underground Road

At present, planning and construction of domestic underground road has entered a rapid development period, respected by Beijing and Shanghai. Reasonable and effective arrangement of escape passage is the necessary precondition to ensure personnel successful self-help and external rapid rescue when underground road is during a fire. However, suitability and effectiveness of escape passage is still unclear, lacking corresponding design standard to refer. On the basis of personnel safety evacuation rules and the most unfavorable evacuation scenario, aiming at cross passage and up and down escape staircase, personnel evacuation fundamental parameters, reasonable cross section type and safety spacing limit value are studied by using typical project cases, evacuation experiment and evacuation numerical simulation. The major studies and achievements are as follows:(1) Based on the systematical arrangement of a large number of engineering cases, considering general characteristics of underground road in urban center and using evacuation risk and rescue convenience as the evaluation index, the escape passage classification system of underground road was built, which answers the applicability of different evacuation pattern and provides fundamental basis for the selection of escape facility in underground road.(2) Carried out cross passage evacuation experiment under different passage widths and spacing in the transverse evacuation platform. The relationship between passage width and personnel evacuation efficiency was obtained and the critical exit width of cross passage was found by continuously observing capacity change of cross passage with width from 1.2m to 2.0m. Personnel complete evacuation time was got and relationship between cross passage spacing and evacuation time was analyzed by decomposing evacuation process and observing personnel net evacuation time under passage spacing from 200m to 400m.(3) Carried out escape staircase evacuation experiment under conventional staircase width (0.8m) in the vertical evacuation platform, which ascertains evacuation performance of escape staircase, reveals cluster flow law and queuing phenomenon in the bottleneck, and proposes reasonable arrangement pattern and crowd relief suggestions of up and down escape staircase.(4) Inherited classical evacuation simulation model of underground road. Corrected key evacuation analysis parameters (such as evacuation speed and passage capacity) of the model by introducing measured value to raise accuracy and credibility of simulation. Verified the relationship between safety evacuation time and passage spacing and put forward upper limit control value of cross passage spacing through evacuation simulation under cross passage spacing from 200m to 500m. Obtained relationship between staircase width and personnel evacuation efficiency and put forward effective staircase width and accepted upper limit of staircase spacing through evacuation simulation under different staircase spacing for four groups staircase with width from 0.8m-1.4m.(5) Considering personnel evacuation behavior theory and characteristic phenomenon in the evacuation experiment, further put forward optimum setting pattern for two kinds of evacuation passage, which can provide scientific guidance for the performance-based design of underground road escape passage.