Effect Of Electric/Magnetic Field Activated Water On Properties Of Cement Mixture

With the rapid development of science and technology,the previous cement concrete composition contains water,cement,sand and stones,but this can not meet the needs of social progress now.Thus,the fifth and sixth components of the cement concrete appear in succession-admixtures and mineral admixtures,which are clearly an integral part of high performance concrete,however,the emergence of new things will inevitably bring some drawbacks,for example,the most important thing is the pollution problems in the production process to environment,once the emissions of pollutants can not be dealt with in strict accordance with requirements,contrary to the national environmental sustainability policy,this is not conducive to the environment-friendly society.Therefore,the neglected raw materials—water,has become a research hot spot nowadays.At present,many researchers have used external electric or magnetic field,laser radiation and other methods to change the nature of mixing water,improving the activity of water,and further use it to mix cement-based materials,making cement hydrate sufficiently and improving cement mixture performance.In this paper,the effect of electric and magnetic field activated water on the performance of cement admixture is studied by combining theoretical explanation and experimental tests.This experiment is divided into two parts: electric field and magnetic field.The electric field experiment includes high voltage electrostatic field activation water,high frequency electric field activation water and alternating voltage applied to the cement mixture,The experimental results were compared with ordinary water and concluded.Magnetic field experiment is made by homemade magnetizing device,select three experimental parameters,design a different magnetic field strength(280,450,650,800mT)? water velocity(0.4,0.6,0.7,0.9,1.0m/s)and the number of water cycles to study the effect of magnetic activated water on the performance of cement mixtures.The research ideas start from the structural properties of water,explain and analyse the activation principle of electromagnetic field,and then combine the cement hydration reaction theory to verify that the activated water can improve the performance of cement mixture.It is explained that the activated water can accelerate the hydration reaction of cement and make the reaction more fully,generate more hydration products to make the structure of cement mixture more compact,improve the fluidity and mechanical properties of cement mixture.The experimental results show that,compared with non-activated water,in some specific experimental conditions,electromagnetic field activation of water can improve the performance of cement mixture,but there is no absolute superiority,mainly includes:(1)Compared with ordinary water,under the action of 2400 V high voltage electrostatic field,water treated for 60 minutes can improve the fluidity of cement paste,and when high frequency electric field is 15 MHz,water treated for 30 minutes has a great effect on the fluidity of cement paste,under the action of 15 V AC voltage,the fluidity of cement paste mixed with activated water is the biggest;(2)When the magnetic field strength is of 280 mT,water flow rate is of 1.0m/s,the fluidity of cement paste reaches a maximum value of 111.13 mm,and the magnetized water can improve the compressive and flexural strength of cement mortar to a certain degree,when the water-cement ratio of 0.5 is constant,the amount of cement is reduced by 6.7%,compressive strength of cement mortar mixed with magnetized water is increased by 3.9%.