Numerical analysis of the thermal active restrained shrinkage ring test to study the early age behavior of massive concrete structures

2011 ◽  
Vol 33 (4) ◽  
pp. 1390-1401 ◽  
Author(s):  
M. Briffaut ◽  
F. Benboudjema ◽  
J.M. Torrenti ◽  
G. Nahas
Keyword(s):  
Numerical Analysis ◽  
Concrete Structures ◽  
Ring Test ◽  
Early Age ◽  
Restrained Shrinkage ◽  
Massive Concrete

Fly-Ash Concretes of 50% of the Replacement Ratio to Reduce the Cracking in Concrete Structures

2013 ◽  
Vol 405-408 ◽  
pp. 2665-2670 ◽  
Author(s):  
Ming Jie Mao ◽  
Qiu Ning Yang ◽  
Wen Bo Zhang ◽  
Isamu Yoshitake
Keyword(s):  
Fly Ash ◽  
Concrete Structures ◽  
High Volume ◽  
Pozzolanic Reaction ◽  
Strength Development ◽  
Early Age ◽  
Replacement Ratio ◽  
Fly Ash Concrete ◽  
Massive Concrete ◽  
Normal Strength

Fly-ash concrete used in massive concrete structure has superior advantages to reduce hydration heat. On the other hand, the fly-ash concrete has negative property of low strength development at early age because pozzolanic reaction of fly-ash activates at mature age, such as after 28 days. To investigate these characteristics of fly-ash used in concrete, the present study discusses thermal cracking possibility of fly-ash concrete by using FE analysis software. The present study employs prediction formulae proposed by Zhang and Japanese design code in the simulations. The objects in this study are normal strength concrete mixed of fly-ash up to 50% of replacement ratio to cement. The comparative investigations show that temperature effect is more significant than strength development at early age. Based on the analytical study, high volume fly-ash concretes of 30-50% of the replacement ratio can be concluded as effective and useful materials to reduce the cracking possibility in massive concrete structures. Keywords-Fly-ash concrete; Early Age, Prediction Formulae for Strength; Thermal Stress Analysis

An Evaluation on the Restrained Shrinkage of Ultra-High Performance Concrete

2012 ◽  
Vol 525-526 ◽  
pp. 449-452 ◽  
Author(s):  
Jung Jun Park ◽  
Doo Yeol Yoo ◽  
Sung Wook Kim ◽  
Young Soo Yoon
Keyword(s):  
High Performance ◽  
High Performance Concrete ◽  
Tensile Creep ◽  
Ring Test ◽  
Early Age ◽  
Restrained Shrinkage ◽  
Reinforcing Bars ◽  
Ultra High Performance Concrete ◽  
Shrinkage Cracking ◽  
Coarse Aggregates

Since ultra-high performance concrete (UHPC) is subject to large occurrence of shrinkage at early age due to its low water-to-cement ratio, the mixing of large quantities of powdered admixtures and the absence of coarse aggregates, UHPC presents large risks of shrinkage cracking caused by the restraints provided by the form and reinforcing bars. Accordingly, this study intends to evaluate the shrinkage behavior of UHPC under restrained state by performing restrained shrinkage test using ring-test. The test results reveal that increasing thickness of the inner ring increases the tensile creep at early age leading to the reduction of the average strain and residual stress of the inner ring.

Effects of early-age thermal behaviour on damage risks in massive concrete structures

2012 ◽  
Vol 16 (5) ◽  
pp. 589-605 ◽  
Author(s):  
Matthieu Briffaut ◽  
Farid Benboudjema ◽  
Jean-Michel Torrenti ◽  
Georges Nahas
Keyword(s):  
Thermal Behaviour ◽  
Concrete Structures ◽  
Early Age ◽  
Massive Concrete

Shrinkage Cracking of High Performance Concrete Mixed with Steel Slag Admixture

2011 ◽  
Vol 462-463 ◽  
pp. 867-871 ◽  
Author(s):  
Yun Feng Li ◽  
Hua Xun Guo ◽  
Ling Ling Wang
Keyword(s):  
High Performance ◽  
High Performance Concrete ◽  
Steel Slag ◽  
Concrete Structures ◽  
Mineral Admixtures ◽  
Maintenance Cost ◽  
Shrinkage Stress ◽  
Early Age ◽  
Restrained Shrinkage ◽  
Shrinkage Cracking

Cracking due to the restrained shrinkage stress has been frequently observed at early age in concrete structures. Early-age deterioration of concrete due to cracking and higher maintenance cost for poor durability cause serious troubles to concrete structures. Steel slag includes a certain scale mineral such as C2S and C3S, and can be applied in cement and concrete as mineral admixtures. Two tests are outlined to quantify the behaviour of concrete under restrained shrinkage using plate and ring specimens. The results show that mineral admixtures can be used to reduce cracking in concrete. The risk of cracking can be estimated for steel slag concrete, so that it will improve the durability of concrete structures.

Sign in / Sign up

Export Citation Format

Share Document