Numerical Analysis Research Of Resistance Variation About Damaged Reinforced Concrete Slab

Mainly aiming at one of the important problems on sluice safety assessment—structure security evaluation, structure mechanical characters were mainly studied according to sluice structure types. The paper proposed the important view of using slab members to evaluate structure safety instead of beam members used in domestic, and mainly researched sluice structure damage in using owing to environment, material, exterior load and so on. Preliminary statistics of correlation between structure damage and time factors were conducted, and some regulations were obtained. Besides, numerical analysis theory exploration and simulation research were performed by it due to maximum load capacity of the state under slab eccentric compression, and variation regularities of slab resistance strength were gained primarily. Main work and achievements are as follows:1. On the basis of finite element method basic principle, separate model on bond-slip stress variation between steel bar and concrete was built, and the relations of theoretical and calculated tension stress releasing was obtained. Besides, the paper recommended to adopt minimal steel ratio to improve calculation convergence.2. The solving methods of material nonlinearity equations were described, and appropriate solving method combined with research object in this paper was selected. Furthermore, solution setting plan of convergence torlerance less than 5 percent under the both control of two-dimension force and displacement norm was proposed aimed at convergence norm of equation solution according to author experiences.3. In view of variation of bond-slip relationship on steel corrosion and concrete, relevant experiments were carried out, and experimental data was statistically analyzed. These tests offered important basis for bond-slip relationship in numerical analysis.4. Aiming at characteristics of slab concrete strength change with time, strength variation range and grade demanded in simulation on slab member resistance test were designed and concrete ratio was presented mainly according to spot safey examination of yellow river middle and lower reaches.5. Based on steel corrosion and concrete strength variation, sluice structure characters and key members, test plans of slab members were designed. Prototype configuration as geometric model 1:3 proportion was reduced, and test physical characters have been alterated correspondingly. Moreover, both reinforcing method and steel corrosion plan of slab member were investigated, and 12 groups 24 slabs in all were poured. The above work established important foundation for resistance strength test research.6. Based test plan, general finite element program ANSYS11.0 platform and typical eccentricity, nonlinear finite element numerical simulation analysis of whole prosess was developed under the state of eccentric compression of reinforced concrete slab. Above research and conclusion play an important role and significance for further study of"preliminary research of slab ultimate bearing capacity under eccentric compression based on the deficiencies"(Youth Research Fund of Centrol non-profit research institute, HKY-2008-16).