The Research And Practical Application Of The Self-densifying High Performance Concrete In The Aspect Of Structure

Self-densifying high performance concrete is well-performing concrete with the good performance of fluidity, anti-segregation and filling-up-space. With its own gravity and without any vibration, it can automatically fill up the space in and between fixed shutters and form self-densified concrete structure of ideal dynamic property and durability, therefore, it can accelerate construction progress of a building, shorten the construction period, secure concrete quality and improve the building's durability. In the mean time, it is conducive as well for environment protection and effects remarkable social and economic efficiency.The research and practical application of the self-densifying high performance concrete in China is still at the initial stage, and property of the said concrete verifies a lot due to difference of material from various regions. Basing on test, research and practical application of the said concrete in this region, this essay is aimed at concluding the regularity of its working performance and dynamic property, developing its products of grades most in use, and promoting its popularization and practical application in our country.To best achieve the working performance of the said concrete, with the help of theology theory in the research, we have analyzed the principle of free-vibration densifying and shaping of mixed concrete, that is, with the perquisite of fluidity, the concrete should have good property of filling-up-space, penetration through voids of fixed steel reinforcement, adherence and prevention from losing water and segregation, and the conflict between anti-segregation and deforming capability should be sorted out. Using processed March cylinder, tapered circular mould, U-shaped instrument, L-shaped concrete fluidity instrument and some other testing instruments, and after research and study to physical and chemical property of various raw material. Systematic tests have been carried out in respect of consistency between cement and additive, concrete fluidity, concrete filling-up-space and penetration capability and concrete anti-segregation property, basing on prudent and careful analysis to results of 34-time tests and more than 500 data, and with utilization of combined additive, we finally conclude the proper mix design range for the self-densifying high performance concrete with ideal working performance at all respects.With the prerequisite of meeting requirement of its working performance, the mix design of common grades can be concluded though strength test if we check various property of the said concrete with the certain mix design, such as compressive strength, tensile strength, elastic modulus, reinforcement wrapping strength, leakage resistance, shrink property and charring resistance, and compare them with property of ordinary concrete, we will find that the various dynamic property of self-densifying high performance concrete is very satisfactory and the durability is quite ideal.After library researches and test, we have applied the new material to shear wall of a multi-story residential building, and inspection and test results have proved the success.Being tested by practical application, the working performance standard and mix design methodology for the self-densifying high performance concrete as above stated are feasible, practical and reliable, therefore it lays the foundation for further development of the said concrete in wide realm.