| Underground engineering by groundwater erosion for a long time,and groundwater penetration with the building depth and increase,acrylic emulsion waterproof material,good performance,green environmental protection,very fit the waterproof and impermeable requirements of underground engineering.But at present,its high performance and low cost can not be taken into account,and there are deficiencies in the research of impermeability characteristics of underground engineering.In order to solve the above problems,this paper prepared waterproof coating by using acrylic emulsion(pure acrylic emulsion)and styrene acrylic copolymerization emulsion(styrene acrylic emulsion).It not only overcomes the problems of high cost and low strength of pure propyl emulsion to prepare waterproof coating,but also makes up for the shortcomings of poor effect of styrene propyl emulsion waterproof coating.The impermeability test is researched and designed innovatively,and the impermeability of underground engineering waterproof coating is revealed.In this paper,16 groups of orthogonal tests were designed to determine the initial ratio.Through the investigation of the properties of the film,the effects of acrylic emulsion composite ratio,alcohol ester dodecyl,sodium hexametaphosphate solution on the film properties were analyzed.Single factor test was carried out to optimize the ratio of two groups with better performance,and the effects of heavy calcium mesh number and defoamer on the tensile strength,fracture elongation,impermeability,impermeability and drying time of the film were investigated.The results show that:(1)The anti-seepage characteristics are mainly manifested as drum on the surface of the coating under the action of water pressure and continuous pressure drum rupture and seepage.The maximum and minimum difference of hydraulic pressure between the drum and seepage water in the same ratio is 0.8MPa and 0MPa.Proper adjustment of the ratio in practical engineering will leave enough time for the disposal of seepage problems in underground engineering.(2)When the composite ratio of two component waterproof coating pure propyl emulsion and styrene propyl emulsion was 0.37,5% sodium hexametaphosphate solution,wetting agent,alcohol ester 12,coupling agent,defoamer accounted for3.75%,0.2%,2.5%,0.3%,0.7% of the liquid components,respectively;The mass ratio of solid component 800 mesh heavy calcium to 1250 mesh talc was 9:1;When the ratio of solid component to liquid component is 0.93,the comprehensive performance of the coating is the best.The tensile strength and fracture elongation were 1.11 MPa and316%,respectively.The water pressure of drum and seepage is 0.8MPa and 1.4MPa.(3)With the increase of the dosage of alcohol esters,the elongation at break increases and the tensile strength decreases.The effect of sodium hexametaphosphate on the mechanical properties of the film is not obvious,too much sodium hexametaphosphate will make the film crack;The defoaming agent can improve the fracture elongation of the film and the defoaming agent can improve the tensile strength of the film,while the plasticizing agent can reduce the tensile strength.The film performance was enhanced with the increase of the number of heavy calcium mesh.The tensile strength of the coating decreases with the increase of the ratio of pure propyl emulsion to styrene propyl emulsion... |
