Experimental Study On Improving The Mechanics And Sulfate Corrosion Resistance Of Rubber Lightweight Aggregate Concrete By Water Glass

The recycling rate of industrial waste such as rubber and fly ash is low,and it has been widely used in the construction field in recent years.Pumice is rich in mineral resources in Inner Mongolia.In order to reduce the burden on the environment and develop a green economy,rubber,fly ash,and pumice can be used in concrete to improve the frost resistance and sound insulation performance of the concrete and reduce the weight of the concrete.However,the addition of these materials will also reduce the strength of concrete,and alkaline excitation is an important method to increase the strength of concrete.Therefore,in this article,different amounts of water glass are added to the lightweight rubber aggregate concrete,and 20%fly ash is used instead of cement.The concrete is subjected to mechanical tests,SEM tests,and NMR tests to study the changes in the mechanical properties of the concrete under the action on water glass modification and excitation.The mass loss rate and relative dynamic elastic modulus are measured through the freeze-thaw cycle test of clear water and the sulfate freeze-thaw cycle test.Combined with the results of microscopic freeze-thaw tests,the frost resistance of lightweight rubber aggregate concrete was explored.The following conclusions are drawn through experimental analysis:(1)Through SEM test and EDS test,it is concluded that OH~-produced by water glass hydrolysis can modify the surface of rubber.With the increase of water glass content,the modification effect is enhanced.After modification,the rubber powder has a positive effect on concrete mechanics and frost resistance.(2)The incorporation of water glass can optimize the mechanical properties of rubber lightweight aggregate concrete.Its compressive strength increases first and then decreases with the increase of water glass content.The compressive strength of c oncrete reaches the best when the water glass content is 2%..Water glass can improve the mechanical properties of 80 mesh rubber concrete,making it basically the same as the28d strength of 20 mesh rubber concrete with optimal content.The rubber lightw eight aggregate concrete can reduce cement consumption by 20%while ensuring its strength.(3)Perform logarithmic function curve fitting on the strength of water glass rubber lightweight aggregate concrete of various ages,and use the measured data to es tablish a BP neural network fitting model.Through data comparison,it is found that the stability of the BP neural network prediction model and the comprehensiveness of the parameters are It is better than the curve fitting model.(4)Through the freeze-thaw cycle test of fresh water and the freeze-thaw cycle test of 5%sodium sulfate brine,it is concluded that the freeze-thaw of 20 mesh rubber lightweight aggregate concrete is better than that of 80 mesh rubber lightweight aggregate concrete,and the freeze-thaw of 20 mesh and 80 mesh rubber lightweight aggregate concrete The optimal content of water glass in the cycle test is 2%.