Prestressed Time-Limited Aging Analyses of Concrete Containment Structure

Abstract

For prestressed concrete containment structure, prestress loss is a key factor that affects the performance of containment structure. Therefore, prestressed time-limited aging analysis (TLAA) is essential for containment structures. The main objective of prestressed TLAA is to assess the safety of containment structures after prestress loss occurred over time. This paper takes the in-service containment structure as an example to investigate the method of TLAA for grounted prestressed containment structure. Firstly, it introduces methods for prestressed TLAA. Secondly, a finite element model of containment structure is established to calculate the minimum required value (MRV) of prestress. The numerical model is verified by the pressure test results. Thirdly, prestress loss of tendons is calculated. Finally, the residual prestress of tendons are compared with the MRV of prestress to confirm whether the containment can service in a certain period. This study can provide guidance for goouted prestressed TLAA of containment structures.

Two-Way Time-Dependent Prestress Losses of Prestressed Concrete Containment with Bonded Prestressing Strands

“…Considering the importance of precision of concrete creep models in predicting the prestress loss of prestress concrete containment, both the early-age and hardened concrete made of type V cement were examined through tests by Song and Kim [6] and compared with the predicted results of creep-prediction equations in several design specifications as well as the Bažant and Panula's model [7]. Cai et al [8] proposed a standard method of time-limited aging analysis of grouted prestressed concrete containment by means of the results of site investigation and finite element analysis. Lundqvist and Nilsson [9] compared the prestress losses obtained from in-service inspections and those estimated using several prediction models for creep, shrinkage, and relaxation in design codes in an attempt to increase the accuracy of the models and modified the existing expressions for the development of shrinkage using the findings on the humidity and temperature inside two Swedish containments.…”