Preparation And Study Of Performance Of Environmental Fireproof Coating For Tunnel

With the increase of traffic density,tunnel has got great attention by planners due to convenient and flexible,the number is increasing.Tunnel fire occurs frequently at home and abroad,because the complexity of transport and structure of tunnel.The top priority of the construction of tunnel is fire protection.It's a good way that spray fireproof coating on the lining structure of tunnel for the fire protection,which is convenient,efficient and low-cost.In this paper,we developed the tunnel fireproof coating,which has adva ntage of low density,high bond strength,well fire resistance,nontoxic and well weather-resisting,by choosing raw materials,determining basic formula,testing on each raw materials which has an effect on the performance of coatings,optimizing the formula,determining optimal formula and comparing with the tunnel fireproof coatings existed,to the poor fire resistance and adhesion of the coating,on the basis of the existing research of tunnel fireproof coating.The group of bond in this study contains high alumina cement,Portland cement and redispersion emulsoid powder,they work together and contribute to high bond strength,the bond strength of the optimal formula is 0.8Mpa,which is far more than the Specification,which requires the bond strength is 0.1Mpa;the group of insulation filler includes expanded vermiculite,expanded perlite and so on,they not only have well performance of fire-resistance but also have low density,which is 597 Kg/m3;the system of foaming and flame retardant respectively composed by melamine,pentaerythrotol,ammonium polyphosphate,aluminum hydroxide,magnesium hydroxide and zinc borate,on one hand,the system of foaming can inflate and bring bubbles at high temperature,then the gaps of the fireproof coating will be filled with the bubbles,so that it can prevent temperature rely effectively,on the other hand,zinc borate can do well with the other two flame retardants,finally we know the fire resistance of the optimal formula is 204min;the group of the assistant contains super plasticizer and entraining agent,they work together and contribute good workability of the optimal formula of tunnel fireproof coating.