Application Research Of Porous Concrete In Tunnel Drainage In Karst Area

As a new building material integrating structure and functionality,porous concrete has been widely used in road engineering in recent years.In order to effectively control the water damage of tunnel pavement in karst area,this paper firstly carried out non-destructive testing tests on porous concrete specimens based on industrial CT scanning technology,and analyzed and analyzed the structural characteristics of porous concrete pores with the help of image processing technology and three-dimensional reconstruction technology.Secondly,the multi-point geostatistics method was used to reconstruct the pores of porous concrete,and the uncertainty of the reconstruction effect was evaluated at the same time.After that,numerical simulation technology was applied to calculate and characterize the seepage effect of porous concrete,and the differences were analyzed.The influence of pore structure characteristics on the drainage performance of porous concrete.Finally,the construction process and operation points of the tunnel porous concrete drainage pavement were summarized by building the test section,and the following conclusions were drawn:(1)Using non-destructive testing,image processing technology and three-dimensional reconstruction technology to obtain porous concrete pore models of different dimensions,and compared with the porous concrete pore model reconstruction based on multi-point geostatistics method,the results show that the two are more consistent High,multi-point geostatistical reconstruction of porous concrete pore model can be used as an effective supplement to the original modeling method,and the combination of the two methods can be widely used in the study of porous concrete pore reconstruction;(2)The pores of porous concrete mainly exist in the form of connected pores,with only a small amount of non-connected pores,and the larger the aggregate particle size,the greater the pore connectivity rate of porous concrete.When the porosity of the porous concrete is less than 12%,it will affect the connectivity of the pores of the porous concrete.When the porosity of the porous concrete is less than 7.7%,the connected pores disappear completely;(3)The connected porosity,critical pore radius and effective pore radius of porous concrete have a positive exponential relationship with the drainage performance of porous concrete.The tortuosity of porous concrete has a negative exponential relationship with the drainage performance of porous concrete;(4)In order to treat the water damage of the tunnel pavement,a set of pavement structure for the drainage pavement of the tunnel was designed;through the material composition design test,the porous concrete meeting the road performance was prepared,and a complete set of tunnels was summarized through the construction of the test road relying on the physical engineering.Construction process and operation points of porous concrete drainage pavement.