Study On Green High Performance Concrete And Sensitivity Analysis Of RC Structural Reliability

Based on the National "973" Program, "Research on Green High Performance Concrete", and transverse scientific research item, quality control to surgery building engineering of Wuhan Xiehe hospital, green high performance concrete (GHPC) and application thereof to high-rise buildings, sensitivities of reliabilities with and without time varying of reinforce concrete structure and members to random variables are systemically studied in this paper.The design method for orthogonal experiment and theory for deviation analysis are used to find out all kinds of responsible proportions between factors such as water-binder ratio, cement or cementing material content in per cubic meter of concrete, and contents of water reducer and flyash, and coarse aggregate type, and variety of cement. The permeability, workability, 28d compressive strength and adiabatic temperature change are taken as test indexes. For the first time, on the basis of the theory of valve engineering, three-parameters principle is proposed for design optimization of GHPC. Farther, four-functions principle is proposed for design optimization of GHPC based on adiabatic temperature change control to mass concrete.It is proposed that the temperature field of mass concrete of foundation in high- rise is actually interaction one of soil and concrete. And the model for interaction field is built up and the solutions thereof from explicit difference and Stehfest method are studied. And Matlab program is developed to calculate interaction temperature field. The results shows that the theoretic values by the model are in consistence with test ones very well.The sensitivity indexes without dimension are respectively defined about distributing parameters sensitivity and parameters sensitivity in limit state functions so as to compare the magnitude of sensitivity to reliability index from random variables. In the terms of sensitivity indexes, sensitivities of reliabilities are analyzed for reinforcement concrete (RC) axial-compressive members, flexural members, and shear members, and big and small excursion-compressive members, in which resistances are respectively considered to be varying and to remain constantly with time. And sensitivity rules for these members are summed up due to large numbers of calculating examples.Two familiar destroy formats, bending destroy and shearing destroy, appear to RC frame columns under seism action. The columns destroy is considered as a series system made up of bending failure mode and shearing failure mode in this paper. And the failure probability of the column due to shearing destroy prior to bending destroy, i.e, so-called strong shear weak bending is analyzed. Farther analysis is applied to sensitivity of design reliability for strong shear weak bending column to random variables.Based on section reliability analysis of RC members, a method for computingreliability of RC frames systems has been developed with full consideration of the structural plasticity, rotation performance of plastic hinges, and correlation between failure sections. Banding PNET method and failure tree method together, the method that is named PFT method can be used to analyze sensitivity of RC frames systems to random variables. It is more simple and accurate than other methods available up to date.Some problems about this research worth to be studied afterward are put up in the end of the paper.