The Mechanical Properties Of The Active Powder Concrete And The Sulfate Erosion Test

Reactive powder concrete(RPC)for short is a new kind of high performance cement-based composites,it has high strength,good toughness,good durability,good features such as volume stability.Usually adopt high grade cement in the process of research and pressure molding process,steam curing and high temperature curing makes a high strength of RPC,but its high cost and not widely used.Due to the special geographical environment of our country,the structures in some areas suffer seasonal wet and dry cycle and sulfate erosion damage.The interaction of sulfate erosion and dry and wet cycle makes the life of concrete structures greatly shortened due to corrosion and damage.Therefore,to improve the durability of concrete structure problem is imminent.This article,under the conditions of temperature maintenance,is a systematic study of the selection of materials from RPC,the design and durability of the design and durability,and the use of thin,solid waste like powder ash,slag powder and other parts of concrete,silica,analysis and optimize the effects of various factors on the performance of the RPC performance,and has made certain results.The main research contents and achievements of the paper are as follows:(1)By orthogonal method to study the water-binder ratio,fly ash,silica fume,quartz powder,sand ratio,fiber and water reducing agent on the RPC fluidity and strength,the influence of obtained the factors that affect significantly the performance of RPC,preliminary optimization of the mix proportioning of the RPC parameters.(2)Through a single variable test,the influence of water glue ratio,fly ash,silica fume,silica fume,silica fume,cement-sand ratio,steel fiber and water reducing agent on RPC compressive strength and folding strength was analyzed,and the parameters of the mixture ratio were further optimized,and RPC with good physical and mechanical properties was obtained.(3)Take out the mechanical properties of the first three groups of RPC mix in saturation concentration sulfate solution under dry-wet cycling test.The test results show that the strength of RPC and quality with the increase of the dry-wet cycling times increase before;In the first eight test cycle RPC apparent characteristic has no obvious change,from the ninth test cycle to the 12th test cycle RPC surface erosion phenomenon,but are relatively weak,showing good erosion resistance.