Study On The Application Of Waste Sintered Brick In Permeable Concrete

Sintered clay brick is one of the most important building materials in the last century.With the expiration of the service life of houses built in the last century,it is bound to face demolition and transformation.The disposal of discarded sintered brick has become an urgent problem to be solved.In addition,China encourages the development of sponge city construction at the present stage,so the country has a large demand for permeable materials.Moreover,permeable concrete can reduce noise and alleviate urban "heat island effect".If these waste clay bricks are used in concrete,resource utilization rate can be greatly improved.Because of the physical and chemical properties of clay brick,its absorption of water is high,crushing index is big,the activity is good,accordingly,scientific method disposal and reasonable utilization of construction garbage have great significance to sustainable development,resource conservation,environmental protection.This paper studies the composition of permeable concrete material minimum requirements,using the abandoned sintered brick for preparation of porous concrete base material,will be broken after sintered brick by screening the waste can be divided into different particle size of aggregate,the application of the brick aggregate classification of different particle sizes,modified with different particle size of aggregate,inorganic modification,organic modification and inorganic and organic composite modification,reached the requirements of national standards of the secondary aggregates,in order to strengthen waterproof concrete durability,permeable concrete structure design can be divided into three layers,respectively to three layer structure to optimize mixture ratio,The image method was used to study the influence of internal pore characteristics of pervious concrete on its basic properties,providing a reference for further study of recycled aggregate pervious concrete.Due to the nature of waste sintered bricks,orthogonal experiments were designed to find the pervious concrete mix ratio that conforms to the national standard,which can be put into the market as pervious pavement material.The bottom layer of pervious concrete is prepared from 9.5 ～ 16 mm recycled aggregate of discarded sintered bricks,with a design thickness of 50 ～ 80mm;the surface layer is prepared from 4.75 ～ 16 mm recycled aggregate of discarded sintered bricks,with a design thickness of 50 ～ 80mm;the surface layer is made of 2.36 ～ 4.75 mm recycled sintered bricks and organic solvents,with a design thickness of 15 ～ 20 mm.The corresponding test blocks made of bottom layer,bottom layer and surface layer were designed for mix ratio and tested and analyzed in terms of performance.It was determined that the ratio of bottom layer was recycled aggregate: silica fume: fly ash: cement: brick powder: water: 62.4% : 2.9% : 5.9% :14.3% : 6.2% : 8.3%.The ratio of surface layer to recycled aggregate: silica fume: fly ash:cement: brick powder: water is 61% : 5.5% : 5.5% : 13.6% : 5.8% : 8.6%.When the ratio ofrecycled aggregate to epoxy resin is 85% : 15%,the surface layer achieves the best performance.Through orthogonal test designed with three levels and four factors,the performance of pervious concrete was improved by increasing compressive strength and ensuring permeability coefficient.It was determined that the maximum value of freeze-thaw cycle was F125,while that of pervious concrete with aggregate size of 9.5 ～ 16 mm could only reach F25.Through orthogonal test analysis of variance,the compressive strength of porous concrete factors influencing the strength of the sorting,natural aggregate replacement rate > >polypropylene fiber water-cement ratio > aggregate size,including the influence of the natural aggregate particle size of permeable concrete strength,the strength of the influence factors of permeable concrete permeable coefficient,aggregate size > > polypropylene fiber natural aggregate replacement rate > water-cement ratio,aggregate fraction of the size distribution of permeable concrete permeable coefficient most affected.Finally selected when polypropylene content is 1%,the natural aggregate replacement material was 75%,choice of aggregate particle size of 4.75 ～ 9.5 mm,water cement ratio 0.325 with the best,permeable concrete indicators can meet the requirements of national standards,and polypropylene content is 1%,the natural aggregate replacement material was 50%,the aggregate size selection,water cement ratio of 0.3 4.75 ～ 16 mm system with the permeable concrete compressive strength is19.4 MPa,can also be used as a waterproof layer of the bottom layer and the surface of concrete structure.