The Research And Application About Manufactured Fine Aggregate In Pingchang Jinbao Briage High Performance Concrete

As natural sand shortage and sand-blasting technology and application of mature, its preparation of concrete strength and durability is also getting better and better.PyeongChang study material based on Campbell’s study on the application of machine-made sand in high performance concrete in bridge engineering information, through the practical application of high-performance concrete research, from the selection of raw materials, quality control and optimization of mix proportion to meet the mechanical properties of concrete, and high durability, high stability and high volume.Main research work and results are as follows:Through a large number of documents, outlines the history of HPC background,research, application status and development direction in the future.Engineering research on PyeongChang kampar bridge engineering characteristics and local characteristics of machine-made sand, demonstrates the necessity and feasibility of machine-made sand in high performance concrete.Through documentation and project analysis, determining the research objectives and research content, establish research ideas, techniques, methods of testing, and developing a research plan.Combined with PyeongChang the Campbell bridge project and construction design of concrete mixing ratio, environmental conditions, and adjusted and optimized in the laboratory and field, get the test mix workability, basic physical and mechanical properties based on the optimal mixture ratio, provides engineering and on-site construction mixture ratio adjustment requirements.In accordance with the study plan of the experimental study on performance of concrete:(1) By selecting representative concrete samples 20 groups, experimental study on workability, adjustments on the basis of obtained reached 200-220mm slump, cohesiveness, good water retention and high performance concrete to meet construction and basic requirements. Mix of different strength grade concrete was bleeding rate and setting time of testing, observing the setting time and bleeding and pumpable.(2) Through the concrete compressive strength of blocks 40 groups and splitting tensile strength tests, select the optimize performance concrete mixing ratio, the standard deviation of only 1.842MPa, concrete production for the excellent level of quality, and quality fluctuation of concrete strength, coefficient of variation is only 0.028.By 5d concrete blocks with conditions the concrete compressive strength and static modulus of elasticity in compression test, the test results show that concrete prestressing requirements can be achieved.(3) Through the impermeability of concrete resistance to chloride ion permeability test,early testing of crack resistance durability tests,test results show that not only has the high strength of high performance concrete and has excellent impermeability, but adverse impact on the early crack resistance, should be overcome in the course of construction.(4) Based on the solid strength of concrete test, structure solid strength of proof to meet the design requirements, further evidence that application of research results in practice is feasible.