Preparation Technology And Performance Analysis Of Pervious Concrete

Pervious concrete is an ecological concrete.Its main structure is composed of a skeleton and a void.It uses coarse aggregate with a single particle size as the skeleton,which is little or no fine aggregate,and cement as a cementitious material.After mixing well with water,it is made into pervious concrete after a series of processes such as molding and curing.At present,the country vigorously promotes the green environmental protection process of the city,strives to build a "sponge city",and builds a harmonious relationship between human and nature.The development trend of cities in the future will also return to nature.The so-called"sponge city" is to transform the city's infrastructure,increase the versatility of basic building facilities,and form a "sponge" without puddles on rainy days and alleviating the surface temperature on sunny days.This article responds to the country's call for green building,optimizes the mix ratio of pervious concrete,independently develops new types of enhancers,and fully recycles construction waste,so that pervious concrete can be better applied to pavement construction in cities with heavy rainfall and more effectively solve urban "Heat island effect" and the drop of groundwater level.In addition,in terms of urban noise,it also plays a role of sound absorption and noise reduction,thereby improving people's living environment.The main research contents and results of this article are as follows:(1)Research on the mix ratio of pervious concrete.According to the design principle of concrete mix ratio,analyze the parameters such as porosity,aggregate particle size and water-cement ratio,comprehensively consider the requirements of the strength and water permeability of the pervious concrete,and use the model test empirical formula to design and calculate the pervious concrete mix ratio.The test results show that the optimal mixing ratio is 413.6 kg of cement,1470 kg of stone,124.1 kg of water,4.1 kg of emulsifier,and 3.8%of cement content in the enhancer.(2)Macroscopic properties of pervious concrete.Pervious concrete test pieces with design specifications of 100mm×100mm×100mm and ?100mm×50mm are tested for 7d and 28d compressive strength and water permeability.Combined with chloride ion content detection,ultraviolet light weather resistance test and freeze-thaw cycle test,the results all meet the requirements of GJJ/T135-2009"Technical Regulations for Pervious Cement Concrete Pavement".(3)Research on the proportion of the new enhancer.Starting from the properties of workability,impermeability and compressive strength of concrete,the appropriate components of the new enhancer are selected and compared with the test results of commercially available enhancers.XRD and infrared spectrum(FTIR)are also used at the same time.The technology make in-depth analysis of the raw material composition and performance of the enhancer,and conclude that the best new enhancer was composed of 78%silica fume,21%potassium lignosulfonate,and sodium silicate with a content of less than 10%.(4)Research on recycled aggregate pervious concrete.Four factors and three levels is designed with water-cement ratio,recycled aggregate content,sodium silicate content,and emulsifier content as the changing parameters.Using the volume method and orthogonal test method,the analysis of variance is obtained.The optimal solution is D1,C2,A1,and B2,that is,the emulsifier content is 1%of the cement content,the sodium silicate content is 3%of the cement content,and the mass ratio of the natural aggregate and the recycled aggregate is 1:0.45 and The water-cement ratio is 0.35.(5)Microscopic properties of pervious concrete.The perfect skeleton-void structure is formed inside the pervious concrete,which not only meets the strength requirements of the project,but also meets the ecological and environmental protection pervious and breathable requirements.Besides,the radiant results of the new enhancer for pervious concrete and recycled aggregate pervious concrete both meet the requirements of Class C and A decorative materials.Figure[39]table[39]reference[101]...