Test Research Of Modified Cement Concrete Containing Scrap Rubber Powder

As a kind of solid waste,the quantity of scrap tyre is increasing rapidly year by year.It not only takes up of land,but may also cause environment problems.So how to deal with the scrap tyre has become an emergent problem all around the world.There are researches present that putting rubber piece(powder) into cement concrete can improve its toughness.And also can make concrete having some properties such sound insulation,heat insulation,good energy absorption,good absorption of shock and better durability etc.In this paper,80mesh,100mesh,120mesh,and 150mesh rubber powder whose average size are similar to the bubbles which the air entraning agent made are added to the control concrete by the quantities of 10kg/m~3,20 kg/m~3,30 kg/m~3 derectly.Do some researches on the freeze resistance tests.At the same time,fresh concrete mechanical property,freeze resistance, crack resistance etc are also tested.Finally,reveals the influence of these characters by the quantity and size of rubber particles.The results show that:(1) after added fine rubber powers,the apparent density decreases by the increasing of rubber quantity.But the fine rubber particles pad the holes of the concrete make the concrete's density doesn't decrease rapidly by adding 100,120,150mesh rubber.The slump of rubberized concrete is increased by the decreasing of rubber size.(2) The rubberized concrete's compressive resistance,flexure resistance decrease by the rubber powder quantity increasing,but the toughness increase.And the elastic modulus decrease.(3) In order to remove the zinc stearate in rubber particles,do some pretreatment which put rubber particles in NaOH liquid to improve the cohesion of rubber particles and paste matrix and increase the strength of concrete.But the result shows that the compressive strength of rubber concrete doesn't increase markablely.(4) Putting fine rubber particles whose size are equal to put lots of "bubbles",the freeze resistance improved markablely,and the hole structure of concrete is improved.(5) Rubber is elastic;its entraining can improve the cracking resistance of rubberized concrete.The concrete containing 120mesh rubber particles have the best properties.Adding 10kg/m~3 can improve freeze resistance markablely.And contrast with other three size particles,it gets better strength.