Experimental Study On Reparation Of Ecological Permeable Brick With Slag

Blast furnace slag is a type of waste discharged from a blast furnace during smelting iron production.The slag production is 25%-50% of the pig iron output.Slag is often used in road construction,backfilling,production of mixed materials and cement.However,the overall utilization rate of slag is not high,and the remaining part has no purpose.It will also invade the land,causing river channels and traffic jams and damaging the ecological environment.At present,the increasing scarcity of water resources has become a global problem,especially in China.China is a country with low precipitation but flooding.With the concept of the sponge city,people are increasingly aware of the importance of improving the ecological environment.Therefore,for the construction of a sponge city,the supporting facilities for permeable pavement are the key.For these severely water-scarce cities,the promotion of pervious bricks has played a positive role in protecting groundwater levels.In rainy weather,rainwater can quickly infiltrate into the ground through permeable bricks to relieve the pressure in the city's interior and make groundwater replenish.After consulting related literature and research,it is concluded that the use of slag to produce ecologically permeable bricks is technically more reliable than that used to substitute stone materials in cast-in-place concrete.The use of slag to make ecological permeable bricks makes extensive use of waste slag,preventing waste of resources,encroachment of land,pollution of soil,water resources and air environment,and achieving win-win economic and social benefits.In this paper,according to the structural characteristics of the ecological permeable bricks and the current status of their functions,a systematic experimental study has been conducted on the mix ratio design method,physical-mechanical properties and preparation process of the permeable bricks.The main research contents and results are as follows:(1)Considering the influence of permeability coefficient and strength of pervious bricks in a comprehensive manner,the volumetric method is used to test the mix ratio design of ecological pervious bricks.(2)Mixture ratio design of pervious bricks: Study of various parameters(water-cement ratio,sand particle size,silica fume infiltration,water-reducing agent permeation,compression load)on pervious brick performance(pervious to water,compressive strength,flexural resistance,The impact of wear resistance and frost resistance.Through experimental research,the optimum water-cement ratio of pervious bricks is about 0.3-0.4,and the proportion of silica fume is appropriate(2%of cement quality).In the case of ensuring the strength of concrete permeable bricks,the less water-reducing agent is,the better the water-permeability is,and the compressive strength and flexural strength of the permeable bricks are decreasing.The frost-resistance of concrete permeable bricks is better.The size of compaction load is inversely proportional to the permeability of water.The higher the compaction load,the higher the compressive strength and flexural strength,the smaller the length of the grinding pit,the higher wear resistance,and the better the antifreeze performance.(3)The design and technical requirements for permeable brick facing,leveling layer,base layer,cushion,soil foundation and drainage were introduced respectively.The excavation of permeable brick roadbeds,the laying of cushions,the laying of basic layers,the laying of leveling layers and The paving process was described.