scholarly journals Durability Of Advanced Cement-Based Materials Used As Repairs For Deteriorated Concrete

2021 ◽  
Author(s):  
Keikhosrow Tahmureszadeh
Keyword(s):  
Bond Strength ◽  
High Performance Concrete ◽  
Construction Material ◽  
Advanced Technology ◽  
Repair System ◽  
Freeze Thaw ◽  
Thaw Cycle ◽  
Cement Based Materials ◽  
Strength And Durability ◽  
Durability Performance

With advanced technology, the production of strong construction material becomes more feasible. However, use of such materials as repairs on top of existing concrete is challenging, since repair system relies not only on the quality of repair but also on the interaction and compatibility of such material with the substrate. Studies regarding the durability of bond strength are limited. Therefore, the objective of this research is to compare the bond strength and durability performance of advanced cement-based materials including ultra-high performance concrete (UHPC), engineered cementitious composite with slag (ECC-Slag), specialized repair material with self-consolidating properties (SCC), and normal concrete (NC) under two common deterioration modes in Canada (freeze-thaw cycles with de-icing salt, and volumetric expansion of the substrate). The freeze-thaw cycle results show higher bond strength and durability performance for UHPC and NC, respectively. Under expanding deterioration, NC started with higher bond strength and UHPC revealed the best durability performance.

scholarly journals Durability Of Advanced Cement-Based Materials Used As Repairs For Deteriorated Concrete

2021 ◽  
Author(s):  
Keikhosrow Tahmureszadeh
Keyword(s):  
Bond Strength ◽  
High Performance Concrete ◽  
Construction Material ◽  
Advanced Technology ◽  
Repair System ◽  
Freeze Thaw ◽  
Thaw Cycle ◽  
Cement Based Materials ◽  
Strength And Durability ◽  
Durability Performance

With advanced technology, the production of strong construction material becomes more feasible. However, use of such materials as repairs on top of existing concrete is challenging, since repair system relies not only on the quality of repair but also on the interaction and compatibility of such material with the substrate. Studies regarding the durability of bond strength are limited. Therefore, the objective of this research is to compare the bond strength and durability performance of advanced cement-based materials including ultra-high performance concrete (UHPC), engineered cementitious composite with slag (ECC-Slag), specialized repair material with self-consolidating properties (SCC), and normal concrete (NC) under two common deterioration modes in Canada (freeze-thaw cycles with de-icing salt, and volumetric expansion of the substrate). The freeze-thaw cycle results show higher bond strength and durability performance for UHPC and NC, respectively. Under expanding deterioration, NC started with higher bond strength and UHPC revealed the best durability performance.

Assessment of sulfate attack and freeze–thaw cycle damage of cement-based materials by a nonlinear acoustic technique

2016 ◽  
Vol 50 (2) ◽  
Author(s):  
Jun Chen ◽  
Rendy Bharata ◽  
Tingyuan Yin ◽  
Qingdong Wang ◽  
Hao Wang ◽  
...  
Keyword(s):  
Sulfate Attack ◽  
Freeze Thaw ◽  
Thaw Cycle ◽  
Acoustic Technique ◽  
Cement Based Materials ◽  
Freeze Thaw Cycle ◽  
Nonlinear Acoustic

Influence of Curing Age and Water-Binder Ratio on Chloride Permeability under Freeze-Thaw and Load

2013 ◽  
Vol 405-408 ◽  
pp. 2610-2615
Author(s):  
Lei Hong ◽  
Run Min Duo
Keyword(s):  
Diffusion Coefficients ◽  
High Performance ◽  
High Performance Concrete ◽  
Chloride Diffusion ◽  
Chloride Permeability ◽  
Freeze Thaw ◽  
Thaw Cycle ◽  
Binder Ratio ◽  
Water Binder Ratio ◽  
Curing Age

The chloride diffusion coefficients of different water-binder ratio high performance concrete (HPC) subjected to different one-way loads，freeze-thaw cycles and different standard curing ages were measured by electro-migration (RCM) tests and the results were analyzed. The test results indicate that with the increase of one-way load, its influence on the chloride permeability of different water-binder ratio HPC rises in the same proportion. The influence of the curing age on the chloride permeability of HPC will decrease with the reduction of the water-binder ratio of HPC. Under the same freeze-thaw cycle conditions, the relationships between chloride diffusion coefficients of different water-binder ratio HPC and curing ages are nearly suitable to power function.

Comparison of Multiple Freeze-Thaw Cycles of High-Performance Concrete Test Beams and Concrete Beams Loaded Test

2013 ◽  
Vol 351-352 ◽  
pp. 570-573
Author(s):  
Zhi Qiang Li ◽  
Xian Chun Zheng ◽  
Xiao Hong Cong
Keyword(s):  
Mechanical Properties ◽  
Concrete Structure ◽  
High Performance ◽  
High Performance Concrete ◽  
Concrete Beams ◽  
Reinforced Concrete Structures ◽  
Experimental Basis ◽  
Freeze Thaw ◽  
Thaw Cycle ◽  
Freeze Thaw Cycle

This study focuses on the following: analysis of the basic mechanical properties of freeze-thaw cycles BFRP composite; freeze-thaw cycle on BFRP reinforced concrete structures force performance; provide experimental basis for the the basalt FRP freeze-thaw environment concrete structure andtheoretical support.

scholarly journals Influence of Hydrophobic Coating on Freeze-Thaw Cycle Resistance of Cement Mortar

2019 ◽  
Vol 2019 ◽  
pp. 1-12
Author(s):  
Zijian Song ◽  
Zhongyuan Lu ◽  
Zhenyu Lai
Keyword(s):  
Surface Energy ◽  
Chemical Modification ◽  
Cement Mortar ◽  
Mass Loss Rate ◽  
Water Contact ◽  
Freeze Thaw ◽  
Hydrophobic Coating ◽  
Low Surface Energy ◽  
Thaw Cycle ◽  
Cement Based Materials

Due to the porous characteristics of cement-based materials, they are often corroded by salt solutions, which results in decreased durability, especially against damage under freeze-thaw cycles (FTCs). Improving surface properties is an effective way to improve the durability of these materials. In this study, a hydrophobic coating was applied to the surface of cement mortar by chemical modification of low surface energy materials. Fourier transform infrared spectroscopy (FT-IR) showed that low surface energy substances are linked to hydration products through chemical bonds. A water contact angle test indicates that the surface of cement mortar changed from hydrophilic (θ = 14°) to hydrophobic (θ = 140°) after chemical modification. The cumulative water uptake of hydrophobic samples decreased by 90%. Meanwhile, the wear resistance of the hydrophobic coatings was excellent. Compared with the baseline sample, mass loss rate, flexural strength, and compressive strength of hydrophobic coating samples increased several-fold in the FTC test. Microstructural changes of the mortar were characterized by scanning electron microscopy. The results show that a hydrophobic coating can significantly improve the freeze-thaw resistance of cement-based materials. The formation of a hydrophobic layer on the surface of cement-based materials can improve their durability. The research results not only have applications in civil engineering but will also have great impact in the restoration of historic structures.

scholarly journals Chloride Induced Corrosion and Carbonation in 3D Printed Concrete

2021 ◽  
Vol 7 (1) ◽  
pp. 1
Author(s):  
Jean De’M Malan ◽  
Algurnon Steve van Rooyen ◽  
Gideon P. A. G. van Zijl
Keyword(s):  
Carbon Dioxide ◽  
Flexural Strength ◽  
Bond Strength ◽  
Lack Of Fusion ◽  
Durability Properties ◽  
Chloride Induced Corrosion ◽  
3D Printed ◽  
Strength And Durability ◽  
Durability Performance ◽  
Interlayer Bond

The durability of reinforced concrete structures is dependent on the ability of the concrete cover to combat the ingress of chlorides and carbon dioxide in marine and urban environments. In recent years, interest in additive manufacturing), specifically referring to extrusion based three-dimensional concrete printing (3DCP), has been growing in the construction industry. Despite this being a promising technology that can save construction time, costs and resources, certain issues regarding the lack of fusion between subsequent printed layers have been brought to light. Research has shown that the lack of fusion at the interlayer regions can act as ingress pathways for corrosion contaminants, such as carbon dioxide and chloride aqueous solution, that can cause deterioration. This study investigates the interlayer bond strength (flexural strength) and durability performance of 3D printed concrete subjected to pass times between 0 and 30 min and compares the results to reference cast concrete of the same concrete mixture. The durability study includes Durability Index testing (oxygen permeability, water sorptivity and chloride conductivity index), accelerated concrete carbonation and chloride-induced corrosion. The results show that the cast samples outperform printed samples, yielding greater flexural strength and durability properties, and emphasize the importance of improving the 3DCP interfacial bond. Cast samples are shown to have randomly distributed, compact voids compared to the interconnected and elongated pores located at the interlayer regions of printed samples. In addition, printed samples yield lower interlayer bond strength and durability properties with an increase in pass time, which is attributed to surface moisture evaporation as well as the thixotropic behaviour of the concrete mixture. Good relationships between the mechanical strength and durability performance are also presented.

scholarly journals Mechanical Behavior and Frost-Resistance of Alkali-Activated Cement Concrete with Blended Binder at Ambient Curing Condition

Buildings ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 52
Author(s):  
Biruk Hailu Tekle ◽  
Klaus Holschemacher ◽  
Philipp Löber ◽  
Björn Heiden
Keyword(s):  
Flexural Strength ◽  
Construction Material ◽  
Source Material ◽  
Conventional Concrete ◽  
Freeze Thaw ◽  
Study Results ◽  
Strength And Durability ◽  
Source Materials ◽  
Alkali Activated ◽  
Alkali Activated Cement

Concrete is the most commonly used construction material because of its various advantages, such as versatility, familiarity, strength, and durability, and it will continue to be in demand far into the future. However, with today’s sensitivity to environmental protection, this material faces unprecedented challenges because of its high greenhouse gas emissions, mainly during cement production. This paper investigates one of the promising cement replacement materials, alkali-activated cement (AAC) concrete. Being produced mainly from byproduct materials and having a comparable structural performance to conventional concrete, AAC concrete can transform the construction industry. Mechanical properties such as compressive and flexural strength and the relationship between them are studied. Different source materials such as fly ash (FA), ground granulated blast furnace slag (GGBS), silica fume (SF), and Metakaolin (MK) are used. The effect of the source materials and the activator solutions on the concrete performance is studied. Furthermore, the freeze-thaw resistance of the concrete is studied. The study results showed that the behavior of AAC depends highly on the source material combinations and type used. The effect of the alkaline solution is also dependent on the source material used. Mixes with higher GGBS content showed the highest strength, while mixes with MK showed the highest flexural strength. The freeze-thaw test results showed that proper design of AAC concrete with lower water content is critical to achieving a good resistance.

Study on Frost Resistance of High Performence Concrete Resistance to Chloride Ion

2012 ◽  
Vol 174-177 ◽  
pp. 1312-1316
Author(s):  
Sheng Ai Cui ◽  
Yue Zhong Ye ◽  
Sheng Tan Dou ◽  
Fei Fu
Keyword(s):  
Frost Resistance ◽  
High Speed ◽  
High Performance ◽  
High Performance Concrete ◽  
Chloride Ion ◽  
Freeze Thaw ◽  
Slag Powder ◽  
Thaw Cycle ◽  
Freeze Thaw Cycle ◽  
Electric Flux

Taking bridge pile of Beijing-Shanghai high speed railway as background, this paper studies frost resistance of high performance concrete resistance to chloride ion, including double-doped mineral (fly ash and slag powder) concrete, two minerals and preservative composition concrete. Quick frost method was adopted in the freeze-thaw cycle test, and frost resistance of high performance concrete was assessed by relative dynamic modulus of elasticity and mass loss ratios. Meanwhile, the electric flux values of specimens were measured after freeze-thaw cycles for assessing chloride ion penetration. Test results show: The frost resistance of both C35, C50 double-doped mineral concrete and C35 two minerals and preservative composition concrete is good, and chloride ion permeability is very low after freeze-thaw cycles.

scholarly journals Mechanical Behaviors and Frost-Resistance of Alkali Activated Cement Concrete with Different Binder Systems

2020 ◽  
Author(s):  
Biruk Hailu Tekle ◽  
Klaus Holschemacher ◽  
Philipp Löber ◽  
Björn Heiden
Keyword(s):  
Flexural Strength ◽  
Greenhouse Gas Emission ◽  
Construction Material ◽  
Source Material ◽  
Conventional Concrete ◽  
Freeze Thaw ◽  
Strength And Durability ◽  
Source Materials ◽  
Alkali Activated ◽  
Alkali Activated Cement

Concrete is the most commonly used construction material due to its various advantages, such as versatility, familiarity, strength and durability and it will continue to be in demand far into the future. However, with today’s sensitivity to the environmental protection, this material is facing unprecedented challenges due to its high greenhouse gas emission mainly during cement production. This paper investigates one of the promising cement replacement materials, alkali activated cement (AAC) concrete. Being produced mainly from byproduct materials and having a comparable structural performance to conventional concrete, AAC concrete has a potential to transform the construction industry. Mechanical properties such as compressive and flexural strength and the relationship between them are studied. Different source materials such as fly ash (FA), ground granulated blast furnace slag (GGBS), silica fume (SF) and Metakaolin (MK) are used. The effect of the source materials and the activator solutions on the concrete performance is studied. Furthermore, the freeze-thaw resistance of the concrete is studied. The results of the study showed that the behavior of AAC depends highly on the source material combinations as well as type used. The effect of the alkaline solution is also dependent on the source material used. Mixes with higher GGBS content in general showed the highest strength while mixes with MK showed the highest flexural strength. The results from the freeze-thaw test showed that proper design of AAC concrete with a lower water content is critical to achieve a good resistance.

Experimental Study on Freeze-Thaw Resistance Durablilty of High Performance Concrete

2010 ◽  
Vol 168-170 ◽  
pp. 393-397 ◽  
Author(s):  
Jun Fang Huo ◽  
Xiao Xia Ji ◽  
Hui Yang
Keyword(s):  
Fly Ash ◽  
Large Volume ◽  
High Performance ◽  
High Performance Concrete ◽  
Test Results ◽  
Freeze Thaw ◽  
Thaw Cycle ◽  
Freeze Thaw Cycle ◽  
Resistance Performance ◽  
Maximum Weight Loss

Freeze-thaw cycle experiments on high performance concrete were carried out while cement was respectively replaced by fly ash for 30%～50%. The test results showed that maximum weight loss rate of concrete was 1.78% and minimum relative dynamic elastic modulus was 94.08% after 300 freeze-thaw cycles for high performance concrete based on low water-cement ratio, efficient air-water-reducing agent and large quantities of industrial waste fly ash. The test data were far less than limits of 5% and 60% in specification. Freeze-thaw resistance performance of high performance concrete with large volume fly ash was excellent according to test results. The high performance concrete with large volume fly ash can meet the requirements of frost resistance performance of concrete in the cold regions. Particularly, it can be fit for the railway concrete engineering.

Sign in / Sign up

Export Citation Format

Share Document