Study On The Basic Properties Of Concrete Prepared From Marine Raw Materials

To explore chlorine salt from seawater and sea sand and stone basic performance of concrete,the influence of the test to explore the sea sea sand concrete and water stone concrete,concrete in bottom of sea sand stone,the water of the sea sea sand stone concrete?hereinafter referred to as Marine concrete of the preparation of raw materials?and ordinary concrete,a total of five kinds of concrete,respectively research in seawater immersion and the mechanical properties and durability of the wet and dry environment.The main research results of this paper are as follows:?1?The effect of Marine raw materials on the mechanical properties of concrete was studied through the compressive strength and splitting tensile strength tests of the specimens,and the conversion relationship between the compressive strength and splitting tensile strength of the concrete prepared by Marine raw materials was obtained through regression analysis.The results show that the Marine raw materials have obvious influence on the mechanical properties of concrete,and the incorporation of Marine raw materials can improve the compressive strength and splitting tensile strength of concrete.?2?The durability studied in this paper includes carbonation resistance,anti-permeability,anti-freezing and shrinkage resistance.The results show that the concrete prepared from Marine raw materials has better carbonation resistance and impervious performance than that of ordinary concrete under the condition of short-term seawater immersion,but the frost resistance is worse,and the shrinkage value is higher than that of ordinary concrete.terials in seawater immersion condition are better than that in seawater dry-wet circulation condition.In the case of short-term seawater immersion,seawater corrosion improves the mechanical properties and durability of concrete,while in the case of long-term seawater immersion,seawater corrosion reduces the mechanical properties and durability of concrete.?3?Marine raw materials of concrete in seawater immersion conditions of compressive strength,splitting tensile strength,carbonation resistance,permeability resistance and freeze resistance performance are better than in seawater dry-wet circulation condition,in the short term,sea water,sea water corrosion of concrete compressive strength,splitting tensile strength,carbonation resistance and impermeability resistance,in the long-term water immersion,sea water corrosion reduces the concrete compressive strength,splitting tensile strength,carbonation resistance and permeability resistance.?4?According to the microstructure analysis,the C₃A hydration product in ordinary Portland cement and the Friedel's salt generated by Cl^-in the concrete prepared by Marine raw materials did not form a large number of holes in the concrete prepared by Marine raw materials,but the volume became smaller and the shrinkage value became larger.In the short to medium term,Cl^-enters into the concrete prepared by Marine raw materials.It mainly plays a physical adsorption role and is absorbed around the pores in the concrete,so as to optimize the pore structure and improve the compactness.Therefore,the mechanical properties and durability of the concrete prepared by Marine raw materials are improved.In long-term seawater immersion,Cl^-enters into the concrete prepared by Marine raw materials,which mainly plays a role of chemical bonding and forms Friedel's salt.As a result,the volume becomes smaller and pores are formed in the concrete,which reduces the mechanical properties and durability of the concrete prepared by Marine raw materials.Therefore,the microstructure analysis results are in good agreement with the experimental results.