scholarly journals Bayesian update of the residual life of a concrete structure using inspection data

2019 ◽  
Author(s):  
Gaowei Xu ◽  
Viliam Makis
Keyword(s):  
Concrete Structure ◽  
Residual Life ◽  
Bayesian Update ◽  
Inspection Data

Residual Life Assessment of Steam Generators With Alloy 600 TT Tubing: Methods and Application

2010 ◽  
Vol 132 (10) ◽  
Author(s):  
Ian de Curieres ◽  
Marie-Christine Meunier ◽  
Pierre Joly
Keyword(s):  
Residual Life ◽  
Tube Bundle ◽  
Life Assessment ◽  
Alloy 600 ◽  
Steam Generators ◽  
Initiation And Propagation ◽  
Primary Water ◽  
Residual Life Assessment ◽  
Inspection Data ◽  
Steam Generator Tubes

The aim of the paper is to introduce methods to estimate the residual life of steam generators with alloy 600 thermally treated (TT) tubing, taking into account primary water stress corrosion cracking (PWSCC) as the main contributor damage. The methods take into account both initiation and propagation of PWSCC cracks in the expansion transition zone of steam generator tubes, as well as the current damage status (cracking and plugging) of the tube bundle, known from inspection results. A probabilistic model is used to treat initiation, while the propagation stage is treated in a deterministic way based on inspection data. After introducing the methods used to assess the residual life, a brief parametric study will be shown to illustrate the effects of initiation versus propagation. Eventually, the cases of a few actual steam generators with tubing made of alloy 600 TT showing different situations of present damage and damage evolution rates will be presented.

scholarly journals Influence of operating time on the corrosion in single-phase and two-phase media

2021 ◽  
Vol 7 (2) ◽  
pp. 127-132
Author(s):  
Valery I. Baranenko ◽  
Olga M. Gulina ◽  
Nikolay L. Salnikov
Keyword(s):  
Residual Life ◽  
Linear Time ◽  
Operating Time ◽  
Repeated Measurements ◽  
Operating Conditions ◽  
Two Phase ◽  
Accelerated Corrosion ◽  
Pipeline Wall ◽  
Inspection Data ◽  
Flow Accelerated Corrosion

Modern foreign computer codes predict a linear growth in the pipeline wall thinning with time due to the process of flow-accelerated corrosion (FAC), i.e. erosion-corrosion wear (ECW). Linear time-thinning dependence and corrosion rate constancy are not however typical of the NPP piping operating conditions. And the associated excessive conservatism of the residual life estimates leads to increased economic costs of repeated inspections. In domestic software tools, EKI-02 and EKI-03, the influence of operating time are taken into account by introducing the respective coefficient into the Chexal-Horowitz model based on the yield of corrosion products into the coolant. The ECW intensity can be however reduced through improvements in operating conditions, preventive measures, improvements in water chemistry, etc., and the use of the dependences once obtained may turn out to be too conservative. Based on a large number of repeated measurements as well as on data from corrosion testers, it has been shown that the influence of time can be described by the function of a particular form, the coefficients of which differ for different units and component and subsystem types. This makes it possible to determine the ‘aging function’ based on inspection data, and then use it in a targeted way for particular components. It has been shown that such estimates are much less conservative.

Residual Life Assessment of Steam Generators With Alloy 600TT Tubing: Methods and Application

2009 ◽  
Author(s):  
Ian de Curieres ◽  
Marie-Christine Meunier ◽  
Pierre Joly
Keyword(s):  
Probabilistic Model ◽  
Damage Evolution ◽  
Residual Life ◽  
Tube Bundle ◽  
Life Assessment ◽  
Steam Generators ◽  
Initiation And Propagation ◽  
Residual Life Assessment ◽  
Inspection Data ◽  
Propagation Stage

The aim of the paper is to introduce methods to estimate the residual life of steam generators with alloy 600TT (thermally treated) tubing, taking into account PWSCC as the main contributor damage. The methods take into account both initiation and propagation of PWSCC cracks in the expansion transition zone of SG tubes, as well as the state of damage (cracking and plugging) of the tube bundle, at a given time, known from inspection results. A probabilistic model is used to treat initiation, while propagation stage is treated in a deterministic way based on inspection data. After introducing the methods used to assess the residual life, a brief parametric study will be shown, to illustrate the effects of initiation versus propagation. Eventually, the cases of a few actual steam generators with tubing made of alloy 600TT, showing different situations of present damage and damage evolution rates will be presented.

Experimentally Derived Cost-Effective Planning of Bridge Deck Rehabilitation by Steel Plate Bonding

1998 ◽  
Vol 1642 (1) ◽  
pp. 21-27
Author(s):  
Tadashi Kanno ◽  
Yasushi Kamihigashi ◽  
Hiromu Ishida
Keyword(s):  
Life Cycle ◽  
Reinforced Concrete ◽  
Bridge Deck ◽  
Steel Plate ◽  
Residual Life ◽  
Cost Effective ◽  
Deck Slabs ◽  
Existing Bridges ◽  
Inspection Data ◽  
Concrete Deck

Rehabilitation cycle is being studied in relation to life-cycle costing based on the realization that making rehabilitation cost-effective would require minimizing the necessary investment. However, the progress of an actual structure’s deterioration cannot be predicted precisely without a collection of inspection data, and therefore, at present the rehabilitation cycle is merely calculated on the idealized progressive deterioration hypothesis. In this study, the optimal life cycle of reinforced concrete deck slabs is derived from the residual life determined through a series of fatigue experiments on deck slabs cut out from existing bridges and rehabilitated afterwards. As a result, precise and cost-effective rehabilitation planning was made possible.

scholarly journals CORROSION IMPACT ANALYSIS ON RESIDUAL LIFE OF STRUCTURE USING CATHODIC TECHNIQUE AND ALGOR SIMULATION SOFTWARE

2018 ◽  
Vol 10 (1) ◽  
pp. 18-26 ◽  
Author(s):  
Chittaranjan Birabar NAYAK ◽  
Nivedita Sunil THROAT ◽  
Sunil Bhimrao THAKARE
Keyword(s):  
Reinforced Concrete ◽  
Service Life ◽  
Dynamic Behavior ◽  
Concrete Structure ◽  
Residual Life ◽  
Simulation Software ◽  
Corrosion Process ◽  
Reinforced Concrete Beams ◽  
Beam Specimen ◽  
Aqueous Environment

Damage to the reinforced concrete structure is mainly occurring because of two reasons either due to end of service life or due to load exceeds beyond structural capacity. Along with these two reasons degradation of material property is the one more major factor which causes the risk of failure. A concrete structure constructed in an aqueous environment get exposed to the corrosion process. Consequently, this causes the generation of crack, fragilization, a decrease of bond strength between reinforcement and concrete. All these factors affection static and dynamic behavior of concrete structure reducing the service life of an affected area. Whereas service life carries the major role in the economy of a concrete structure that is why various methods have been developed in the second half of the 20th century to find out the residual life of the structure. In this proposed work, a non-destructive technique is used to predict the residual life of reinforced concrete beams having different cracking levels, as results of steel reinforcement corrosion, considering the variation produced in the dynamic behavior, through the variation of the first natural vibration frequency. Whereas to accelerate the corrosion process, impress current technique is used in which a current is externally applied to induce corrosion in reinforcement and then crack widths and vibration natural frequencies were measured. A numerical model is proposed with the help of FEM based Auto desk Algor simulation software to predict attack penetration depth. At the end, the paper is concluded by giving an effect of “water to cement ratio” and “cover to diameter ratio” on the initiation and propagation of corrosion and residual life of corroded beam specimen is graphically represented.

Study of Durability Analysis and Evaluation Model for Existing Concrete Structure in Coastal Areas

2013 ◽  
Vol 539 ◽  
pp. 130-138
Author(s):  
Hai Yong Yu ◽  
He Zhang
Keyword(s):  
Concrete Structure ◽  
Residual Life ◽  
Evaluation Model ◽  
Steel Corrosion ◽  
Hangzhou Bay ◽  
Analysis And Evaluation ◽  
Durability Analysis ◽  
Analysis Theory ◽  
Concrete Degradation ◽  
Life Prediction Model

This article put forward the durability state analysis method for existing concrete structure based on the step analysis theory and environmental load feature of east coast in China. Considering the process of both concrete degradation and steel corrosion, this article also established the residual life prediction model of existing concrete structure, based on a whole life prospective period. The model was successfully applied to evaluate the durability state and residual life of certain existing concrete structures, including dock structure in Hangzhou Bay and matching construction of Expo, 2010.

Precast Prestressed Concrete Structure Provides Solution for Getty Center Tram Guideway

PCI Journal ◽  
1995 ◽  
Vol 40 (3) ◽  
pp. 24-39 ◽  
Author(s):  
Mark G. Josten ◽  
Wilfred L. Painter ◽  
James S. Guarre
Keyword(s):  
Prestressed Concrete ◽  
Concrete Structure ◽  
Precast Prestressed Concrete

Tolerances for Precast Concrete Structure

PCI Journal ◽  
1976 ◽  
Vol 21 (4) ◽  
pp. 44-57
Author(s):  
Marvin L. Vander ◽  
H. Carl Walker
Keyword(s):  
Concrete Structure ◽  
Precast Concrete

A method of technical diagnostics for offshore structures

1994 ◽  
Vol 16 (2) ◽  
pp. 43-48
Author(s):  
Do Son
Keyword(s):  
Diagnostic Method ◽  
Joint Venture ◽  
Oil And Gas ◽  
Residual Life ◽  
Life Time ◽  
Offshore Structures ◽  
Technical Diagnostics ◽  
Offshore Platforms ◽  
South Vietnam ◽  
Local Destruction

This paper describes the results of measurements and analysis of the parameters, characterizing technical state of offshore platforms in Vietnam Sea. Based on decreasing in time material characteristics because of corrosion and local destruction assessment on residual life time of platforms is given and variants for its repair are recommended. The results allowed to confirm advantage of proposed technical diagnostic method in comparison with others and have been used for oil and gas platform of Joint Venture "Vietsovpetro" in South Vietnam.

Functional and operational risk as a criterion for assessing the durability of an autonomous energy system

2019 ◽  
Vol 12 (1) ◽  
pp. 56-62 ◽  
Author(s):  
A. O. Nedosekin ◽  
A. V. Smirnov ◽  
D. P. Makarenko ◽  
Z. I. Abdoulaeva
Keyword(s):  
Service Life ◽  
Structural Reliability ◽  
Residual Life ◽  
Fuzzy Random Variable ◽  
Operational Risk ◽  
Energy System ◽  
Technical System ◽  
Residual Service Life ◽  
Technological Parameters ◽  
Residual Service

The article presents new models and methods for estimating the residual service life of an autonomous energy system, using the functional operational risk criterion (FOR). The purpose of the article is to demonstrate a new method of durability evaluation using the fuzzy logic and soft computing framework. Durability in the article is understood as a complex property directly adjacent to the complex property of system resilience, as understood in the Western practice of assessing and ensuring the reliability of technical systems. Due to the lack of reliable homogeneous statistics on system equipment failures and recoveries, triangular fuzzy estimates of failure and recovery intensities are used as fuzzy functions of time based on incomplete data and expert estimates. The FOR in the model is the possibility for the system availability ratio to be below the standard level. An example of the evaluation of the FOR and the residual service life of a redundant cold supply system of a special facility is considered. The transition from the paradigm of structural reliability to the paradigm of functional reliability based on the continuous degradation of the technological parameters of an autonomous energy system is considered. In this case, the FOR can no longer be evaluated by the criterion of a sudden failure, nor is it possible to build a Markov’s chain on discrete states of the technical system. Assuming this, it is appropriate to predict the defi ning functional parameters of a technical system as fuzzy functions of a general form and to estimate the residual service life of the technical system as a fuzzy random variable. Then the FOR is estimated as the possibility for the residual life of the technical system to be below its warranty period, as determined by the supplier of the equipment.

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