Experimental Study On Mechanical Properties And Durability Of Aeolian Sand Concrete

During the 13th five-year plan period,Yulin will invest 50.9 billion yuan to construct 300 key projects,which will definitely lead to the upgrading of construction sand contradiction.The use of aeolian sand instead of river sand to mix aeolian sand concrete reduces the constru ction cost,and also conforms to the national economic development direction of reducing ene rgy consumption,reducing emissions and protecting the environment.In addition,the current s ituation of insufficient supply of river sand in Yulin area has been well postponed.From the p erspective of the national demand for building materials in the region,the research on the engi neering applicability of aeolian sand concrete has been carried out which solves the problem of the northern desert areas building materials production,can fundamentally improve the ecological.environment,also broaden the sources of building sand and ease the pressure from shortage of national infrastructure with sand,then reduce the construction cost.From the perspective of the development of the discipline,the deterioration mechanism of aeolian sand concrete in freezing-thawing durability can be revealed from the microscopic perspective,which can fill the gap in the existing regional aeolian sand concrete durability research,enhance the understanding of aeolian sand concrete durability mechanism and enrich the connotation of this discipline.In view of this,this paper is as follows:(1)This article first has carried on the slump of aeolian sand and early compressive str ength test,experimental study on the two sand ratio,30%and 35%,respectively use 0%,15%,45%,100%of the aeolian sand replacement ordinary river sand,fingding the compressiv e strength of block under the different aeolian sand replacement rate.The research has s hown that with the improvement of aeolian sand replacement ratio,slump and compressive str ength showed a trend of increase after decrease first and sand ratio increased from 30%to 35%when the compressive strength,the use of origin software.(2)When it comes to the aeolian sand replacement rate under different sand ratio an d the block of antifreeze performance,research has shown that with the increase of aeolian sa nd replacement rate,aeolian sand concrete frost resistance first decreased and then increased t he trend,45%below the replacement rate,antifreeze performance is inversely proportional t o the displacement rate,and more than 45%is proportional to the large quantity of aeolian sa nd is to improve its frost resistance performance.When the sand ratio was increased from 30%to 35%,the frost resistance of the test block was improved.The basic theory of damag e mechanics was cited.(3)Study the compressive strength and frost resistance of the test block from the micros copic perspective.The result shows that the number of pores is not the reason to determine th e frost resistance,but affects the compressive strength.The more pores,the lower the compres sive strength.However,the pore area and porosity determine its frost resistance.The smaller t he pore area or the larger the small pores occupy,the lower the porosity,the higher the frost re sistance.(4)Aeolian sand to establish the life prediction model of concrete,due to previous multi-purpose single dosage to characterization of freeze-thaw damage degree,but isn't a single free ze-thaw damage factors,this paper uses relative dynamic elastic modulus and mass loss rate o f double indexes to establish a suitable for life prediction model of aeolian sand concrete,effe cts and the theoretical results fit well with the measured data,to provide a theoretical basis fo r subsequent scholars.