Design and performance evaluation of MKPC paste dry-wet cycle system in sulfate environment
In order to evaluate the mechanical and physical properties of magnesium potassium phosphate cement(MKPC)paste under the coupling effect of dry and wet cycles of sulfate,the dry and wet regimes applicable to the MKPC paste specimens were designed by vacuum saturation and vacuum drying tests at different temperatures according to GB/T 3810.3-2016 test method.The designed wet and dry regimes were followed to test the mass loss and strength change of MKPC specimens under sulfate environment for different number of wet and dry cycles and different ages of full immersion.The test results were as follows:After repeated tests,the MKPC specimen was designed with a dry and wet cycle of 72 h for 1 dry and wet cycle with the rate of change of mass<0.1%for two adjacent times.The flexural strength and compressive strength of MKPC specimens decreased by 24.44%and 18.63%after 120 dry and wet cycles of 5%Na2SO4 solution compared with those of specimens without dry and wet cycles,respectively,with a mass loss of 4.12%.After soaking in 5%Na2SO4 solution for 360 d,the flexural strengths of MKPC specimens decreased by 1.23%compared with those of unsoaked specimens,the compressive strengths of MKPC specimens increased by 1.11%compared with those of unsoaked specimens,with a mass loss of 1.54%.Therefore,MKPC specimens were more sensitive to flexural strength changes and mass loss under the action of wet and dry cycles.
potassium magnesium phosphate cementsulfate attackwet and dry cyclesstrengthmass loss
NETL
NSTL
万方数据
维普
