Research Of The Mix-Sand Concrete

The fine aggregate is one of the basic raw materials of the concrete. The quality of the aggregate plays an important role in workability of flesh concrete and physic mechanics property and duration of the harden concrete. The source of nature aggregate is less and less while the need with the develop of the construction is more and more , this has become a big conflict. Nowadays environment protection and continuable develop had become a develop strategy in the world. How to make full use of the local resource to decrease the cost of producing concrete is a principle of concrete industry. The new national stander GB/T14684-2001 "The sand used in construction" definitely request the production company must to provide the check out certificate of the production which force the supporter to build quality ensure system and promote the application of the machine made sand. The application of fine sand has been one of the character of Chongqing area. But compare with genera concrete, the fine sand concrete has the flowing characters: much cement component, low sand percentage, the conglutination of mix is a little big , concrete abrasion resistance is a little weaker, the shrink is comparative big . These heavily influence the application of fine sand in the road project high compression concrete project and prestress concrete project.Preparation, mechanics property, the long property and the duration of mix-sand concrete were research in this paper . The flowing is result of the research:(1) The preparation design of the mix-sand concrete can flow the preparation of nature sand concrete design, and the compression of concrete achieve the require of the stress guaranteed rate.(2) The modules of mix sand can be change by adjust the proportion of machine made sand and fine sand. There is a relation between the modules of mix-sand and component proportion. There exist a proper modules of the mix-sand which makes the property of mix-sand correspond with the medium modules sand.(3) The mechanics property of the mix-sand concrete almost the same with the medium modules sand concrete and can fully achieve the require of the design.(4) The shrink behave and the creep behave of the mix-sand concrete is the same with the behave of medium modules sand concrete which studied by other researcher.(5) With the higher of concrete design stress the water permeability, gas permeability...