Experimental Study On The Influence Of Microsilica And Basalt Fiber On The Properties Of Rubber Concrete

As the enhancement of transporting industry in our country,numerous discarded tires are increasingly appearing.Putting discarded tires into rubber particles and mixing them into concrete can effectively relieve the stress carried out by discarded tires.Whereas,it will largely diminish the intension and the hardness of concrete as rubber particles are added inside.This problem seriously restricts the application of rubber concrete in construction projects.Micro-silica fiber rubber concrete,as a green composite material,resolves the problem of reduction which is caused by rubber.It enlarges the ability of hitting resistance and initial resistance of concrete from cracking inside.The thesis studied the properties of being dynamic and static on Micro-silica fiber rubber concrete in detail by comparing the early anti-cracking performance and microstructure of micro-silica fume fiber rubber concrete through compression tensile test,SHPB test,early plate crack resistance test and SEM test,so as to find out the optimal dosage of micro silica fume and basalt fiber and their mechanism elaborately.The major research concludes as follows:The volume of micro-silica fume can enlarge the extent of compressive strength and the rupture capacity on Micro-silica fiber rubber concrete.As the blending volume of basalt fiber is stable,the compressive strength value of the rubber concrete will continually grow,based on the increasing number of blending of the volume of micro-silica fume.However,it turns that the pulling resistance and rupture strength show an increase before they drop down.As the blending volume of silica fume is stable,the strength of pulling resistance and the rupture strength will present an increase and then decrease when adding more and more the basalt fiber inside the rubber concrete.When the volumes of two types of the blending adding in the micro-silica fiber rubber concrete meet 3 kg/m3 and 15%,the compressive strength of the rubber concrete attains its maximum.When the volumes of two types of the blending adding in the micro-silica fiber rubber concrete meet 3 kg/m3 and 10%,the strength of pulling and folding resistance on the rubber concrete achieves its maximum.Secondly,in the SHPB test,when the content of micro-silica fume remains unchanged.As the blending volume of micro-silica fume is stable,the compressive strength will have a bit increase and then decrease when adding more and more the inside the rubber concrete.As the blending volume of basalt fiber is stable,the compressive strength will continually increase when adding more and more silica fume inside the rubber concrete.When the volumes of the blending of silica fume and basalt fiber adding in the rubber concrete meet 3 kg/m3 and 15%respectively,the impact compressive strength reaches the maximum.When the content of micro-silica fume keeps unchanged,the fractal dimension of the fragments after crushing appears an increase at the first but then shows a decrease trend when mixing more and more basalt fiber.As the content of basalt fiber in the basalt fiber remains unchanged,the fractal dimension of the fragments after crushing clearly proves a continuous decrease under the enlarging number of inputted micro-silica powder.In addition,within an appropriate dosage range,the fragmentation of rubber concrete which is created by crushing can be improved by the mixing of basalt fiber and micro-silica fume in rubber.The content of micro-silica powder is in the range of 10%～15%,the impact crushing effect is the best andThirdly,after the micro-silica powder and basalt fiber are mixed into rubber concrete at the same time,the length of the early cracks on the surface of the rubber concrete slab is shorter,fewer in number,and smaller in width,and the cracking phenomenon has been very improved;compared with the rubber before improvement In concrete,the early crack reduction coefficient of micro-silica fume fiber rubber concrete is as high as 85.1%;the optimal amount of micro-silica fiber rubber concrete sample has a big improvement in crack resisting with the comparison with the criterion of rubber concrete sampling.Finally,due to the fact that there is a low ability of stickiness between the rubber particles and the cementing material mixed in the rubber concrete,the strength of concrete is obviously cut down.The fiber penetrates the internal cracks,which effectively prevents the cracking inside the concrete,by that increasing the strength of compressive,pulling and folding resistance.However,mass fiber content will cause the fiber The phenomenon of clumping and superposition,thereby reducing the integrity of the concrete,and eventually reducing the strength of compressive,pulling and folding resistance of the rubber concrete.Figure 37 table 12 references 86...