Influence of High-Temperature Curing on the Properties of the Concrete Containing Ground Iron and Steel Slag

2014 ◽  
Vol 507 ◽  
pp. 337-342
Author(s):  
Meng Yuan Li ◽  
Jin Hu
Keyword(s):  
Compressive Strength ◽  
High Temperature ◽  
Steel Slag ◽  
Curing Temperature ◽  
Early Age ◽  
Cement Concrete ◽  
Chloride Permeability ◽  
Iron And Steel ◽  
Negative Effect ◽  
Curing Condition

The influence of high-temperature curing on the compressive strength and chloride permeability of the concrete containing ground iron and steel slag (GISS) was investigated. Under standard curing condition (20°C), the early-age compressive strength of the concrete with GISS is much lower than that of the pure cement concrete. The activity of GISS is more sensitive to the increase of curing temperature than that of cement. The increase amplitude of early-age strength of the concrete with GISS is much greater than that of the pure cement concrete by increasing curing temperature. Increasing curing temperature tends to decease the late-age strength and enhance the late-age permeability of concrete. The negative effect of increasing curing temperature on the late-age properties of the concrete with GISS is smaller than that of the pure cement concrete.

scholarly journals Effect of the Curing Condition and High-Temperature Exposure on Ground-Granulated Blast-Furnace Slag Cement Concrete

2021 ◽  
Vol 15 (1) ◽  
Author(s):  
Eskinder Desta Shumuye ◽  
Jun Zhao ◽  
Zike Wang
Keyword(s):  
Compressive Strength ◽  
High Temperature ◽  
Elevated Temperatures ◽  
Curing Temperature ◽  
Stable Phase ◽  
Cement Concrete ◽  
Slag Cement ◽  
High Temperature Exposure ◽  
Curing Condition ◽  
Temperature Exposure

AbstractIn this study, the effect of curing temperature on the properties of slag cement concrete after high-temperature exposure was studied, and elevated curing temperature (45 ± 2 °C and 95% relative humidity (RH)) was selected to compare with the standard curing temperature (20 ± 2 °C and 95%RH). Four different concrete mixes with the same mix proportion, except for different slag replacement ratios, were used: 0% (reference), 30% (slag), 50% (slag), and 70% (slag). After high-temperature exposure at 200, 400, 600, and 800 °C, the effect of slag replacement, high temperature, and curing temperature on the compressive strength and mineralogical and microstructural properties of slag cement concrete were studied. Test results indicated that the compressive strength of concrete cured for 7 d at elevated temperatures increased by 28.2, 20.7, 28.8, and 14.7% compared with that cured at the standard curing condition at slag percentages of 0, 70, 50, and 30%, respectively. X-ray diffraction (XRD) and Scanning electron microscope (SEM) results revealed that concrete cured at elevated temperatures exhibited a more condensed phase and contained a higher percentage of hydrates than that cured for 7 d in the standard curing condition. However, after 56 d of curing, concrete in the standard curing condition exhibited a more stable phase and a higher concentration of hydrates.

Effect of Chemical Composition on the Properties of Reconstructed Steel Slag

2019 ◽  
Vol 944 ◽  
pp. 1163-1171
Author(s):  
Ying Xu ◽  
Qiao Ling Wang ◽  
Chen Guang Hu ◽  
Shan Shan Yang
Keyword(s):  
Compressive Strength ◽  
Steel Slag ◽  
Temperature Reconstruction ◽  
X Ray Diffraction ◽  
Technological Parameters ◽  
Iron And Steel ◽  
X Ray ◽  
Volume Stability ◽  
Cementitious Activity ◽  
Scanning Electron

The steel slag is not widely or extensively used because of its poor volume stability and low cementitious activity. In this paper, the solid waste fly ash, quicklime and slag discharged from iron and steel enterprises are used as conditioning components in the experiment. In order to improve the cementitious activity and volume stability of steel slag, the high temperature reconstruction experiment of steel slag was completed. The effects of C/S (2.50~3.14), S/A (4.5~17. 81) on the cementitious activity and volume stability of reconstructed steel slag were investigated by means of the tests of compressive strength, scanning electron microscope, X-ray diffraction, lithofacies test, stability test and so on. The results showed that the cementitious activity and volume stability of the reconstructed steel slag were improved in the higher C/S or lower S/A. The cementitious activity and volume stability of the reconstructed steel slag were improved with the increase of CaF2 content. By analyzing the cementitious activity and volume stability of the reconstructed steel slag, the optimum technological parameters are obtained as follows: C/S is 2.70 , S/A is 5.78, the content of CaF2 is 4%.

Study on Autoclaved Performance of Pyrite Tailing

2011 ◽  
Vol 233-235 ◽  
pp. 1762-1765
Author(s):  
Lu Zhang ◽  
Shu Ying Wang
Keyword(s):  
Compressive Strength ◽  
Steel Slag ◽  
Curing Condition

Autoclaved characteristics of pyrite tailing are studied mixed different materials by different curing condition. The results show that compressive strength of pyrite tailing autoclaved sample is 0. Pyrite tailing autoclaved sample acquires a higher compressive strength mixed with lime. But effect of gypsum is few on compressive strength of pyrite tailing lime autoclaved system. Mixed pyrite tailing is disadvantage for compressive strength of steel slag autoclaved samples. But a higher compressive strength of steel slag pyrite tailing autoclaved sample is acquired mixed gypsum, and compressive strength of steel slag lime autoclaved sample increases mixed pyrite tailing.

scholarly journals Using the Maturity Method in Predicting the Compressive Strength of Vinyl Ester Polymer Concrete at an Early Age

2017 ◽  
Vol 2017 ◽  
pp. 1-12
Author(s):  
Nan Ji Jin ◽  
Kyu-Seok Yeon ◽  
Seung-Ho Min ◽  
Jaeheum Yeon
Keyword(s):  
Compressive Strength ◽  
Prediction Model ◽  
Vinyl Ester ◽  
Curing Temperature ◽  
Polymer Concrete ◽  
Early Age ◽  
Time Interval ◽  
Study Results ◽  
Maturity Method ◽  
Curing Age

The compressive strength of vinyl ester polymer concrete is predicted using the maturity method. The compressive strength rapidly increased until the curing age of 24 hrs and thereafter slowly increased until the curing age of 72 hrs. As the MMA content increased, the compressive strength decreased. Furthermore, as the curing temperature decreased, compressive strength decreased. For vinyl ester polymer concrete, datum temperature, ranging from −22.5 to −24.6°C, decreased as the MMA content increased. The maturity index equation for cement concrete cannot be applied to polymer concrete and the maturity of vinyl ester polymer concrete can only be estimated through control of the time interval Δt. Thus, this study introduced a suitable scaled-down factor (n) for the determination of polymer concrete’s maturity, and a factor of 0.3 was the most suitable. Also, the DR-HILL compressive strength prediction model was determined as applicable to vinyl ester polymer concrete among the dose-response models. For the parameters of the prediction model, applying the parameters by combining all data obtained from the three different amounts of MMA content was deemed acceptable. The study results could be useful for the quality control of vinyl ester polymer concrete and nondestructive prediction of early age strength.

Influences of Initial Curing Conditions on the Microstructure of Fly Ash Cement System

2010 ◽  
Vol 168-170 ◽  
pp. 532-536 ◽  
Author(s):  
Guo Li ◽  
En Li Lu ◽  
Peng Wang ◽  
Ou Geng ◽  
Yong Sheng Ji
Keyword(s):  
Compressive Strength ◽  
Fly Ash ◽  
Cement Mortar ◽  
Early Age ◽  
Concrete Durability ◽  
Cement Concrete ◽  
Hydration Degree ◽  
Curing Conditions ◽  
Cement System ◽  
C 30

In order to study the influences of initial curing conditions on fly ash (FA) cement concrete durability, fly ash cement samples with 30% replacement ratio were fabricated and cured in water at 10°C, 20°C, 30°Cand 40°C for 3d, 7d, 14d and 28d respectively. Hydration degrees of fly ash at early age were measured using the selective dissolve method. Correspondingly the pore structure and morphology of FA-cement mortar and compared cement mortar were studied by using MIP and SEM methods. Then early age compressive strengths of FA-cement concrete and compared normal cement concrete were tested. Experimental results show that initial curing temperatures and ages are important factors to fly ash early age hydration degree, FA-cement system microstructure, morphology and early age compressive strength etc. High curing temperatures and longer curing time can lead higher fly ash hydration degree, and then higher compressive strength of FA-cement concrete, and make the micro-structures of fly ash-cement system denser.

Effect of Cement-Based Permeable Crystallization Material on the Performance of Deterioration Concrete

2013 ◽  
Vol 368-370 ◽  
pp. 905-910
Author(s):  
Jia Bin Liu ◽  
Hong Gen Qin ◽  
Fei Geng ◽  
Wei Guo ◽  
Chao Ming Pang
Keyword(s):  
Compressive Strength ◽  
Frost Resistance ◽  
Chloride Permeability ◽  
Function Mechanism ◽  
Concrete Deterioration ◽  
Chloride Resistance ◽  
Negative Effect ◽  
Resistance Performance

During the long term service, concrete deterioration will occur due to erosion circumstance, load or unload condition, which will have negative effect on its security and durability. This article mainly discusses the effect of cement-based permeable crystallization material on compressive strength, rebound putative strength, carbonization performance, chloride permeability, and frost resistance of deterioration concrete. The result has shown that cement-based permeable crystallization material can effectively improve the strength, carbonization resistance performance and chloride resistance ability, but for the frost resistance is not obvious. We also analyze the function mechanism of the cement-based permeable crystallization material through ESEM observation.

scholarly journals Activation Energy for the Concrete Maturity Model – Part 1: Compressive Strength Tests at Different Curing Temperatures

2020 ◽  
Vol 62 (1) ◽  
pp. 87-106
Author(s):  
Claus Vestergaard Nielsen ◽  
Martin Kaasgaard
Keyword(s):  
Activation Energy ◽  
Compressive Strength ◽  
Laboratory Tests ◽  
Curing Temperature ◽  
Early Age ◽  
Maturity Model ◽  
Arrhenius Model ◽  
Equivalent Age ◽  
Strength Tests ◽  
Concrete Maturity

AbstractThe article addresses the modelling of the maturity of concrete. The apparent activation energy is the backbone of the Arrhenius model, which is typically used to model the maturity of concrete. The maturity (or the equivalent age) is influenced by the curing temperature and it is applied when modelling the hydration process and the hardening of concrete for instance in order to forecast the early-age strength to determine the time for removal of formwork or the time for prestressing. Part 1 of the article describes the background for the maturity model and the test series carried out at the DTI concrete lab.Laboratory tests at different curing temperatures (from 5°C to 60°C) are presented and the compressive strength results are modelled according to the original Freiesleben Hansen and Pedersen maturity model that has been applied in the field for many years. The tests include five different concretes, using three different cement types and the addition of fly ash. There are significant differences especially when considering the later-age strength modelling at either low temperatures or at high temperature curing.

scholarly journals Experimental study on fiber mortar strength at early age under temperature difference

2019 ◽  
Vol 264 ◽  
pp. 02005
Author(s):  
Yan Zhang ◽  
Ning Li
Keyword(s):  
High Temperature ◽  
Temperature Difference ◽  
Concrete Structure ◽  
Early Age ◽  
Experimental Basis ◽  
Cement Concrete ◽  
Influence Of Temperature ◽  
Mortar Strength ◽  
Strength Change ◽  
Strength Difference

The condition of high temperature is easy to destroy the concrete structure of tunnels. Many temperature difference conditions are applied to ordinary mortar and fiber mortar specimens, the early strength values of mortar caused by temperature change were measured. The flexural strength change rules of the specimens were analysed. The influence of temperature difference on different specimens, and the cause of the strength difference and failure of the specimens are studied. It provides experimental basis for improving the service life of high temperature tunnel cement concrete structure.

Hydration Properties of Steel Slag under Different Curing Temperatures

2014 ◽  
Vol 507 ◽  
pp. 295-299 ◽  
Author(s):  
Bo Zhang ◽  
Jin Hu ◽  
Meng Yuan Li
Keyword(s):  
Compressive Strength ◽  
Pore Structure ◽  
Water Content ◽  
Cement Paste ◽  
Steel Slag ◽  
Pore Distribution ◽  
Curing Temperature ◽  
Hydration Properties ◽  
Evaporable Water ◽  
Temperature Conditions

The non-evaporable water content, compressive strength, and pore distribution of steel slag paste cured under different curing temperature conditions were investigated in this paper. The non-evaporable water content of steel slag paste at early ages is obviously larger at higher curing temperature. At the age of 28 days, the non-evaporable water content of steel slag paste at normal curing temperature is close to that at high curing temperature, but the compressive strength of steel slag paste at normal curing temperature is much lower than that at high curing temperature. The pore structure of steel slag paste is much coarser than that of cement paste under the same conditions.

Sign in / Sign up

Export Citation Format

Share Document