Experimental Study On The Strength Of Self-Compacting Concrete In Low Temperature

The topics were self-compacting concrete mix optimization design and on the basis oftest to study the self-compacting concrete cube compressive strength, prism compressivestrength, cube splitting tensile strength and flexural strength changes in the low temperature.This topics include the following aspects:(1) In order to detemine the optimal dosage volume of mineral admixtures andpolycarboxylate superplasticizer volume content, the paper through experimental study ofwater-cement ratio, volume content of cementitious material, sand ratio of self-compactingconcrete slump, the impact of the expansion degree, T50, poor edges and28d compressivestrength.(2) On the basis of a fixed volume method on gravel, through the combination oforthogonal test and range analysis, stone zisong volume, the volume fraction of sand, water-cement ratio, the volume of fly ash on the primary and secondary sequence of workability ofself-compacting concrete is obtained, as to determine the optimum compacted concrete mix.(3) Through the production of48sets of a total of144150mm specimens,48groups of atotal of144prism specimens, at20℃,10℃,0℃,-10℃,-20℃,-30℃six temperature points,age is3d,7d,14d,28d four time periods, research on self-compacting concrete at lowtemperature cube compressive strength, prism compressive strength variation regularity,splitting tensile strength, flexural strength variation regularity. Summary self-compactingconcrete mechanical properties change with the temperature, low temperature calculationformula of self-compacting concrete at different curing age and temperature the strength ofthe relationship, different temperature curing age and the sterength of the relationship betweenthe intensity ratio, the conversion formula under the premise of self-compacting concreteconversion formula, prism at low temperature, the compressive strength and compressivestrength, splitting tensile strength and the conversion formula of compressive strength andflexural strength and compressive strength.(4) According to analysis and processing of the test data, draw out the self-compactingconcrete cube compressive strength, prism compressive strength, splitting strength, flexuralstrength at low temperature under various diagram.The results show that: with the decrease of temperature, the self-compacting concretecube compressive strength, prism compressive strength, splitting strength, flexural strengthare improved significantly. And low temperature self-compacting concrete prism compressivestrength and cube compressive strength, splitting strength and compressive strength, fleuralstrength and compressive strength are still fixed relationship.