Study On Optimal Mix Proportion Design And Performance Of Ecological Concrete

With the continuous advancement of China’s ecological civilization construction,people’s awareness of environmental protection continues to strengthen,which puts forward new ecological needs for urban river slope protection on the basis of the traditional function of flood control and drainage.It is found that when the ecological concrete with continuous pores is used as the main material of river slope protection project,it can not only meet the strength requirements of engineering structure,but also realize the ecological functions of improving material exchange and purifying water quality,and has broad application prospects.This paper takes Water purification ecological concrete as the research object,adds SR-3special additives,and explores its optimal mix proportion and various properties through orthogonal experiment,compression experiment,permeability experiment,water purification experiment and freeze-thaw cycle experiment.The main conclusions of the experiment are as follows:1.The optimum mix proportion of SR-3 ecological concrete is as follows: the particle size of coarse aggregate is 6 ～ 9mm,the content of SR-3 is 15%(the mass ratio of additives to cement),the sand rate is 10%,and the water cement ratio is about 0.43.2.In the range of experimental variables,with the increase of coarse aggregate particle size,the compressive strength of ecological concrete decreases and the permeability coefficient increases,from 34.3mpa to 18.0mpa and 6.11mm/s to 11.34mm/s respectively;With the increase of SR-3 content,the compressive strength and permeability coefficient of ecological concrete increase from 20.6mpa to 33.6mpa and 6.88mm/s to 9.03mm/s respectively,and have the characteristics of early strength;With the increase of sand ratio,the compressive strength of ecological concrete increases and the permeability coefficient decreases,which increases from 27.3mpa to 33.9mpa and 10.47mm/s to 5.23mm/s respectively;With the increase of water cement ratio,the compressive strength and permeability coefficient of ecological concrete increase first and then decrease in a certain range,and the maximum peak appears at the water cement ratio of about 0.43,which are34.7mpa and 8.61mm/s respectively.3.Ecological concrete has excellent water purification capacity.In the 30 day water purification experiment,the maximum removal rates of TN,TP and COD are 42%,72.5%and 59.2%,respectively.4.SR-3 additive can improve the freeze-thaw durability of ecological concrete.After 45freeze-thaw cycles,the average mass loss rate of the experimental group added SR-3 additive is 5.12% and the relative dynamic elastic modulus is 63%;The average mass loss rate of the control group was 6.47%,and the relative dynamic elastic modulus was 60%.