Study On The Preparation And Testing Of Rubber Concrete Modifier

Rubber concrete has excellent engineering properties, and therefore, the currentresearch and application of rubber concrete at home and abroad is becoming moreand more. But the rubber concrete also has its own limitations, and the root of theproblem is that the reduction of compressive strength. To overcome the limitationsof rubber concrete， that due to the incorporation of rubber particles can lead toreduced strength of the concrete, to improve its own strength and crack resistance,and to increase the practicability we need to start from its additive materials-rubber particles. Study on the modification of rubber particles can change theinternal bond strength of concrete from the microscopic structure, thus improvingthe mechanical properties of rubber concrete, that is, through adding modifiers toimprove the performance of rubber concrete.The paper based on C20concrete, using1-3mm rubber particle and10%of theamount of volume to replace part of fine aggregate to do experiment.By researchdifferent methods of modification to develop appropriate modifier. The modifiedmethods include washing, inorganic solution, organic solution and homemademodifiers,then to prepare standard rubber concrete for mechanical tests andmicroscopic scanning electron microscopy tests. and calculating the loss ofcompressive strength and splitting tensile strength of28d age. This experimentreferences research methods at home and abroad, using water, inorganic solution,organic solution and homemade modifiers to modify the rubber particles, and testingthe mechanical properties of rubber concrete, and then conducting experimentalstudy of its microscopic mechanism. Mechanical tests include standard specimenscompressive strength and splitting tensile strength of28d age before and aftermodification. Microscopic scanning electron microscope tests are to ovserve thechange of rubber particle’s surface and that if the rubber particles are well bondingwith the cement matrix before and after modification.The results showed that: 1) Washing, NaOH solution, KH560solution, KH570solution both canenhance the strength of rubber concrete, and the effect of KH570solution is the best.And inorganic modifier and organic modifier both has an optimum concentration ormass fraction.2) The self-modifying agent甲19-1and sodium silicate made obvious effectcompared with the others, but there is no advantages compared with the silane, so itstill needs improvement.3) The composite effect of NaOH solution and KH570solution is significant,and they had no significant effect on the compressive strength and splitting tensilestrength of rubber concrete in the limitted concentration or mass fraction. But theirmodification process is relatively complex.4) The usage of modifiers is different. We need to wash the rubber particlesafter treatment with inorganic modifiers (three times is appropriate).organic modifiertreated We need to put rubber particles into the oven for heating, setting70degreesin30minutes. The composite modification need to deal with the rubber particleswith inorganic modifier firstly, and then is the organic modifier.