Research On Fire Prevevtion And Noise Reduction Technology Of Long Highway Tunnel

With the increase of tunnel length and traffic density, the potential threat from tunnel fire is increasing, noise pollution is increasingly serious. This dissertation has search into the fire protection and noise reduction of long tunnels,the main contents includes following few aspects:1.The paper analyses the three main factors influencing the performances of concrete in fire through simulating the practical heating curve in the fire(moisture content, strength and aggregate),the results show that the quality loss of concrete is enlargement by the moisture content increasing, also the concrete dekrepitation is more severe; Just for concrete strength, the concrete fire resistance get worse and quality loss enlarge with the improvement of concrete strength; With an increase of thermal stability of macadam concrete, spalling resistance becomes larger. Granite stone concrete has the highest fire resistance,followed by baslt stone concrete, limestone rubble concrete.2. In order to improve the fire performance of the lining concrete,some measures have been taken.The critical moisture content as an evaluation index of concrete resistance to burst test,draws a blowout of fireproof fiber concrete critical moisture content of 79%,but higher than the other three kinds of concrete, also the crack resistance is best;In addition,based on the different dosage of fireproof fiber concrete fire experiment was carried out, It can be seen,Along with the increase in fiber content, concrete after fire damage reduced;The fireproof fiber concrete permeability resistance test,conclud that fireproof fiber concrete permeability resistance is slightly lower than those of normal concrete;In the fire retardant fiber concrete mixed with fly ash, greater degree of improve the permeability resistance of concrete.3. By testing different concrete slab side temperature field and the in the region,can be seen the different concrete slab side temperature field are basically identical,the springback value were small at the same temperature field, present along with the increase of temperature,the springback value loss is enlarge.4. To tunnel noise reduction aspect, based on several kinds of commonly used on the market to test the sound absorption coefficient of sound absorption material, and the test results show that in the average absorption coefficient with effective ability, on the basis of considering different frequencies of sound absorption effect and the tunnel construction convenience, economy, preliminary selected 30 mm thick inorganic fiber coating applied in tunnel lining concrete.5. The mix design is studied in order to improve the anti-sliding and abrasion resistance performance of the low noise exposed-aggregate cement concrete road. The results show that the road performance are excellent when the sand ratio is 20% and the ratio of the aggregate with size of 4.75~9.5mm and that with size of 9.5~13.2mm is 2:1. Compared with the road performance of ordinary cement concrete, it is found that the anti-sliding resistance performance of exposed-aggregate-concrete is greatly improved in the premise of guaranteeing abrasion resistance, also the sound absorption capability of exposed-aggregate cement concrete is doubled.