Dissertation > Excellent graduate degree dissertation topics show

Reaearch on Prediction for Durable Life of Concrete Structures under the Coupling Action of Load and Chlorine Erosion

Author: LiuXin
Tutor: BieSheAn
School: Tianjin University
Course: Hydraulic Engineering
Keywords: chlorine salt erosion initial corrosion time the width of crack prediction for service durability Monte-Carlo method
CLC: TU375
Type: Master's thesis
Year: 2012
Downloads: 4
Quote: 0
Read: Download Dissertation

Abstract


As the main structure forms nowadays, reinforced concrete structure has beenwidely used in harbor and marine engineering. With the growing of using time, alarge amount of reinforced concrete structures face durability damage under chlorinesalt erosion. As a result, service life prediction for reinforced concrete structuresunder chlorine salt erosion is a crucial problem to solve for durability and designevaluation. Besides, in actual engineering, most reinforced concrete structures underload work with crack, and the crack intensifies durability problems. Hereby,according to the most obvious problem of reinforced concrete structure under chlorinesalt erosion among durability problems, the paper builds prediction model for durablelife of reinforced concrete structures under the coupling action of constant load andchlorine salt erosion.First, the paper introduces traditional chloride’s diffusion model in concrete, andsummarizes influencing factors and statistical characteristics of the parameters. On thebasis of this, analysis of the statistical characteristics of initial corrosion time ofreinforcing bar is done with sampling simulation method, and it is found that theyfollow lognormal distribution. The paper finds that surface chloride concentration,critical chloride concentration and cover thickness have significant effect on initialcorrosion time by analyzing sensitivity of the parameters which influence initialcorrosion time.Second, the load and crack width model and the crack width and chlorine salterosion model are built. The models consider the impact of single maximum crackwidth on chlorine diffusion coefficient, the reducing of chlorine diffusion coefficientwith time and the growth of crack width with time. The paper builds2-D chlorinediffusion models with finite differential equations.Third, calculation of an actual project is done with the model of coupling actionof load and chlorine salt erosion. According to the results, chloride ion defuses fasteraround crack and it is better approximated as one-dimensional diffusion far to thecrack. The characteristic, that chloride diffusion coefficient reduces with time, hassignificant impact on diffusion of chloride ion. As is shown in the analysis results ofsensitivity, in order to increase service life, we should think first about the reductionof concrete W/C, and improving concrete cover thickness next. Finally, the paper simulates the change of failure probability with time by usingprobabilistic method——Monte Carlo sampling method. The results show that thecover thickness has great effect on the failure probability of concrete members.Besides, the paper makes comparison of the results of probabilistic method and that ofdeterministic method, and it is found that the latter results are greater that the formerones. So the results of probabilistic method are more conservative.The paper is based on traditional diffusion equation, and builds prediction modelfor durable life of reinforced concrete structures under the coupling action of load andchlorine salt erosion, the results of which can provide theoretical basis for durabilitydesign of concrete structures in marine environment.

Related Dissertations

  1. Transient Thermal Analysis of Multi-Body System with Complicated Boundary Conditions,TK124
  2. Copula Based Simulation Procedures for Pricing Credit Default Swaps,F224
  3. Analysis of Angle Measurement Accuracy Based on Vehicle Photoelectric Theodolites,TH761.1
  4. Chloride erosion and freeze-thaw cycles under high strength bond strength of fly ash concrete,TU528
  5. Research on Computer Aided Tolerance Optimization in Aircraft Manufacturing,V262
  6. The Studies and Applications of Quasi Monte Carlo Methods,O242.2
  7. Heteroskcedasticity Two-way Linear Regression and Using to Test Concrete Strength of Building Structure,F224
  8. Analysis of Elevator Traffic Flow Based on Five Tipical Periods,TU857
  9. Stochastic Optimal Control of Nonlinear Suspension of Quarter Car Model,U463.33
  10. Option Pricing Under Stochastic Crashes,F830.9
  11. The Response Surface Method Based on FEM and Its Application to Reliability Analysis for Gravity Dams,TV642.3
  12. Application of Aeroassisted Orbital Maintenance to Ultra-Low-Orbit Satellite,V448.2
  13. Application of Bayesian Method in Risk Based Inspection,X928.03
  14. Typhoon Wind Hazard Analysis of Shenzhen Based on Wind-Field Model Numerical Simulation,P444
  15. Quality Control and Risk Management of Asphalt Concrete Facing Works for Embankment,TV642
  16. Research on Required Navigation Performance Based on Flight Data,V249
  17. Reliability Research for Key Joints of Large-scale and Complicated Spatial Structure,TU311.2
  18. Research on Thermodynamics and Kinetics of Mechanical Milling-HDDR Process for NdFeB Alloy,TF123.111
  19. The Study and Application of Kinetic Monte Carlo Method in Multiscale Simulation,TM911.4
  20. Evolution of Virtual Instruments Measurement Uncertainty,TP274
  21. T-DAB transmitter design,TN830

CLC: > Industrial Technology > Building Science > Building structure > Concrete structure,reinforced concrete structure > Reinforced concrete structures
© 2012 www.DissertationTopic.Net  Mobile