Variation of Diffusion Coefficient for Selected Binary and Ternary Concrete Mixtures Considering Concrete Aging Effect

2018 ◽  
Vol 761 ◽  
pp. 144-147 ◽  
Author(s):  
Petr Konečný ◽  
Petr Lehner ◽  
Pratanu Ghosh ◽  
Quang Tran
Keyword(s):  
Diffusion Coefficient ◽  
High Performance ◽  
High Performance Concrete ◽  
Chloride Ion ◽  
Aging Effect ◽  
Chloride Penetration ◽  
Concrete Mixtures ◽  
Concrete Properties ◽  
Chloride Ion Penetration ◽  
Non Destructive

The paper deals with the variation of resistance of selected High Performance Concrete (HPC) materials against chloride ion penetration. The resistance of chloride penetration is described by means of the diffusion coefficient and it is derived from emerging non-destructive tests. It is computed from the measurements of surface electrical resistivity (see e.g. AASTHTO TP-95 specification) data. The effect of concrete aging on the diffusion coefficient is taken into account as the concrete properties are time dependent and it is significantly important for High Performance Concrete (HPC) materials.

Influence of Slag Fineness on High-Performance Concrete Properties

2012 ◽  
Vol 174-177 ◽  
pp. 286-290
Author(s):  
Hui Liu ◽  
Yuan Bao Leng ◽  
Wan Zeng Song ◽  
Sheng Bi
Keyword(s):  
Compressive Strength ◽  
Surface Area ◽  
High Performance ◽  
High Performance Concrete ◽  
Chloride Ion ◽  
Penetration Resistance ◽  
Slag Surface ◽  
Concrete Properties ◽  
Chloride Ion Penetration ◽  
Ion Penetration

This research focuses on investigating the high performance concrete containing slag with different fineness and dosage. For this purpose, the workability, compressive strength at different ages, and chloride ion penetration were investigated, with slag surface area 420m2/kg, 530m2/kg, 610m2/kg, and 720m2/kg, and replacement percentage 0%, 20%, 40%, and 60%, respectively. It was found that the workability and chloride ion penetration resistance were affected by the fineness and dosage of slag. The 7-day compressive strength decreased with slag replacement increasing when the fineness of slag is lower than 530m2/kg, and 28-day and 56-day compressive strength increased; For the fineness higher than 530m2/kg, the 7-day compressive strength is higher than that of control concrete, when the slag replacement was 40%, the concrete reached the highest value, and the 28-day and 56-day compressive strength increased with slag incorporation.

Comparison of Diffusion and Chloride Ion Penetration of High-Performance Concrete

2010 ◽  
Vol 168-170 ◽  
pp. 2171-2177 ◽  
Author(s):  
Mohammad Iqbal Khan
Keyword(s):  
Diffusion Coefficient ◽  
High Performance ◽  
High Performance Concrete ◽  
Chloride Concentration ◽  
Chloride Ion ◽  
Chloride Permeability ◽  
Chloride Ion Penetration ◽  
Rapid Chloride Permeability ◽  
Astm C1202 ◽  
Ion Penetration

This paper reports the results of an investigation of chloride ion penetration and diffusion for high performance concrete. Concrete was prepared incorporating pulverised fuel ash (PFA) and silica fume (SF) with various water-binder ratios. Chloride ion penetration was measured at various ages using rapid chloride permeability test in accordance with ASTM C1202-91. Based on experimentally obtained results, isoresponse contours for chloride permeability were developed showing the interactive and optimized effect between the various parameters investigated. Diffusion coefficient of concrete was determined applying Fick’s law of diffusion. The results show that the inclusion of PFA and SF reduced both chloride permeability and chloride concentration of concrete. It was found that rapid chloride permeability values were consistent with diffusion coefficient of concrete.

Influence of Slag Fineness on Durability of High-Performance Concrete

2012 ◽  
Vol 204-208 ◽  
pp. 3240-3243
Author(s):  
Hui Liu ◽  
Ping Li ◽  
Qiao Lan Jin
Keyword(s):  
Compressive Strength ◽  
Surface Area ◽  
Frost Resistance ◽  
High Performance ◽  
High Performance Concrete ◽  
Chloride Ion ◽  
Penetration Resistance ◽  
Concrete Durability ◽  
Chloride Ion Penetration ◽  
Ion Penetration

This research focuses on investigating the high performance concrete durability containing slag with different fineness and dosage. For this purpose, the 28-day compressive strength, chloride ion penetration, and frost resistance were investigated, with slag surface area 420m2/kg, 530m2/kg, 610m2/kg, and 720m2/kg, and replacement percentage 0%, 20%, 40%, and 60%, respectively. It was found that chloride ion penetration resistance were affected by the fineness and dosage of slag, and concrete frost resistance property was mainly controlled by dosage of slag rather than the fineness, and the 28-day compressive strength increased with slag incorporation.

Application and Study of C80 High Performance Concrete in Freezing Shaft Sinking Techniques

2013 ◽  
Vol 353-356 ◽  
pp. 1577-1582
Author(s):  
Qian Wang ◽  
Tong Wei Lu ◽  
Lei Guo
Keyword(s):  
Compressive Strength ◽  
Diffusion Coefficient ◽  
High Performance ◽  
High Performance Concrete ◽  
Chloride Ion ◽  
Test Results ◽  
Mine Shaft ◽  
Deep Freezing ◽  
Thawing Cycle ◽  
Shaft Sinking

A study on C80 high performance concrete used in deep freezing mine shaft liner is made. Test results are listed as follows: (1) Concretes compressive strength at 1 day is 53.0 MPa, while the compressive strength at 28 days is 93.5 MPa. (2) The diffusion coefficient of chloride ion at 28 days is 9.8×10-14m2/s, and freezing-thawing cycle is over 1000 times. The evidence above proves that this concrete can satisfy the requirements of C80 high performance concrete used in freezing shaft sinking techniques.

Literature Review: Mechanical Properties of Hardened Silica Fume Concrete

2014 ◽  
Vol 1008-1009 ◽  
pp. 1357-1362
Author(s):  
Xi Xi He ◽  
Qing Wang
Keyword(s):  
Silica Fume ◽  
High Performance ◽  
High Performance Concrete ◽  
Chloride Ion ◽  
High Strength ◽  
Penetration Resistance ◽  
Pozzolanic Reaction ◽  
Mineral Admixture ◽  
Chemical Attack ◽  
Chloride Ion Penetration

Silica fume (SF) has become an environmental mineral admixture in the production of high-strength and high-performance concrete in modern concrete engineering. Through compacting all components and pozzolanic reaction, obvious mechanical enhancement of concrete is observed in the aspects of compressive strength tensile strength, elastic modulus as well as fracture toughness. Further more, durability improvement of silica fume concrete such as chloride-ion penetration resistance and chemical attack resistance are reported accordingly.

Inner Damage and Anti-Chloride Penetration of High-Performance Concrete under Axial Tensile Load

2011 ◽  
Vol 261-263 ◽  
pp. 1210-1214
Author(s):  
Fu Xiang Jiang ◽  
Lei Xin ◽  
Tie Jun Zhao ◽  
Xiao Mei Wan
Keyword(s):  
Diffusion Coefficient ◽  
High Performance ◽  
High Performance Concrete ◽  
Tensile Load ◽  
Total Porosity ◽  
Tensile Loading ◽  
Chloride Penetration ◽  
Chloride Diffusion ◽  
Uniaxial Tensile ◽  
Chloride Diffusion Coefficient

The total porosity of high performance concrete specimens after different level uniaxial tensile loading were measured to reflect the damage degree of mechanical load to the microstructure of the concrete. Meanwhile, considering the environmental characteristics of the ocean tidal zone, chloride penetration tests of the concrete were carried out with salt solution capillary absorption method. Based on the profile of chloride measured from specimens, chloride diffusion coefficients of the concrete under uniaxial tensile load with different levels are determined further by Fick’s second law. Results show that both of total porosity and chloride diffusion coefficient of the concrete are increased significantly after short-term tensile loading. And the evolutions of the porosity and chloride diffusion coefficient are similar with the development of micro-cracks under uniaxial tensile load.

Study on Resistance to Chloride Ion Penetration of High Performance Concrete for High Speed Railway Bridge Pile

2010 ◽  
Vol 150-151 ◽  
pp. 542-546
Author(s):  
Sheng Ai Cui ◽  
Yue Zhong Ye ◽  
Fei Fu ◽  
Zhi Feng Liu
Keyword(s):  
High Speed ◽  
High Performance ◽  
High Performance Concrete ◽  
Chloride Ion ◽  
Chloride Salt ◽  
High Speed Railway ◽  
Chloride Ion Penetration ◽  
Study Results ◽  
Better Than ◽  
Ion Penetration

Taking bridge pile of high speed railway as background, resistance to chloride ion penetration of high performance concrete is studied. Theoretical analysis and experimental research of chloride ion penetration are carried out for double-doped mineral (fly ash and slag powder) concrete, C35 single mineral and preservative double-doped concrete, and C35 two kinds of minerals and preservative composite concrete. In addition, the test results are compared and analyzed. Study results show: chloride ion penetration grade of double-doped mineral concrete (C35, C40, C45 and C50) is very low. Resistances to chloride ion penetration of C35 single mineral and preservative double-doped concrete are all poor overall, so the scheme is infeasible. By performance comparison of resistance to chloride ion penetration, C35 two kinds of minerals and solid preservative composite concrete is obviously better than C35 two kinds of minerals and liquid preservative composite concrete , meanwhile obviously better than C35 double-doped mineral concrete, and very close to C50 double-doped mineral concrete. And, it can meet resistance to chloride ion penetration requirement under the corrosion environments along the high speed railway line and can be used as high performance concrete to resist chloride salt.

Experimental Research of High Performance Concrete with Multi-Elements Mineral Admixtures

2009 ◽  
Vol 405-406 ◽  
pp. 24-29 ◽  
Author(s):  
Ke Liang Li ◽  
Xiu Sheng Tang ◽  
Guo Hong Huang ◽  
Hui Xu
Keyword(s):  
Mechanical Properties ◽  
Diffusion Coefficient ◽  
High Performance ◽  
High Performance Concrete ◽  
Physical And Mechanical Properties ◽  
Chloride Ion ◽  
Gas Diffusion ◽  
Mineral Admixtures ◽  
Alkali Silica Reaction ◽  
Superposition Effect

Performing the superposition effect of multi-elements mineral admixtures, high performance concrete (HPC) with 3% of silicon fume, 20% of fly ash and 40% of ground granulated blast-furnace slag (GGBS) was prepared, and its physical and mechanical properties and durability were studied systematically. The compressive strength and tensile strength of HPC are better than those of ordinary concrete. HPC has high compactness with smaller gas diffusion coefficient and relative permeability coefficient. Adding volume stabilizer and controlling the contents of SO3 in the GGBS and volume stabilizer at 3%, can reduce dry shrinkages effectively. Large mount of mineral admixture was used to make the concentrations of K+ and Na+ in the pore solution and the expansion caused by alkali-silica reaction depress greatly. So the alkali-silica reaction gets controlled markedly. The effective diffusion coefficient of chloride ion is 1.96×10-12 m2/s, which means HPC has a favorable chloride ion penetration resistance. After 15 times of wet-dry cycle, the rates of the rust area and quality loss of the reinforcing steel bars in HPC are only 4.1% and 0.05% respectively, so HPC has better performance of steel protection. The mortar bar did not expand in corrosive sodium sulfate solution, and it means HPC has better performance of sulfate resistance. The performances of frost resistance and carbonation resistance of HPC are also favorable. It’s proved in tests that the superposition effect of multi-elements mineral admixtures can enhance the physical and mechanical properties and durability of concrete greatly.

Sign in / Sign up

Export Citation Format

Share Document