Experimental Study On Mechanical Properties And Duurability Of Foamed Cement

The bubble light soil is a new lightweight building material,which is a kind of air bubbles,solidified materials,adding materials and other additives,which are mixed by a certain proportion of design.Because of its small density and easy to control,self-reliance good,convenient construction,short process cycle,save project cost,energy saving and environmental protection and other advantages are used in more fields.This paper investigates the application of bubble light soil at home and abroad in recent years,analyzes the characteristics of various materials in the mixed light soil of bubbles and carries out laboratory tests.The engineering waste soil and fly ash are selected as test materials,combined with the common foaming agent in the project and market,three kinds of common foaming agents were selected to prepare the bubble mixed light soil,the physical properties and engineering properties of the foaming agent were tested and screened,the suitable foaming agent and additive were selected as the test materials for the later preparation of light soil,The durability of the mixed lightweight soil is studied,such as adaptability,water absorption,moisture stability,wet and dry,freeze-thaw and solution erosion.The contents of this paper mainly include the following aspects:(1)Three kinds of blowing agent were selected and compared,the foaming agent with good physical properties and economy was selected.(2)Preparation of different additives(silty clay and fly ash)of the bubble light soil,and the physical properties of the mixture(fluidity,bulk density,adaptability),preparation of specimens for later tests.(3)Through the laboratory test to determine the water absorption,durability,chemical corrosion resistance and mechanical properties,and other aspects of performance indicators,analysis of the amount of raw soil,the amount of bubble mixed with the bubble mixture of light soil compressive strength and durability of the correlation between the reasonable range of matching.The following conclusions were obtained in the experiment:(1)The bubbles showed better stability when the 3%-stabilizing agent was added,and the effect of the stabilizing agent was not increased with the increase of bubble group.(2)The content of silty clay and fly ash is controlled in the range of 35%~45% and 60%~65% respectively,and its engineering properties(wet bulk weight,fluidity,adaptability)are better and meet the requirements of construction code.(3)Considering the wet-dry effect on the mechanical properties of the material has a certain weakening effect,the amount of air bubbles should be controlled in the 10%~12% range;The intensity of the bubble light soil increases with the increase of the amount of bubble and the intensity of compressive strength decreases.(4)With the increase of wet and dry cycle,the compressive strength of silty clay system and fly ash system is reduced with different degrees,and the amount of silty clay and fly ash in the range of 50%~67% and 33%~40% is smaller than that of the pressure attenuation of the bubble light soil.