A STUDY ON IMPROVEMENT AND ITS EVALUATION FOR THE SURFACE LAYER OF CONCRETE PLACED WITH PERMEABLE FORM

2012 ◽  
Vol 06 ◽  
pp. 664-669
Author(s):  
RYOICHI TANAKA ◽  
TAKASHI HABUCHI ◽  
TAKAHIKO AMINO ◽  
TSUTOMU FUKUTE
Keyword(s):  
Surface Layer ◽  
Chloride Ion ◽  
Concrete Specimen ◽  
Air Permeability ◽  
Permeability Test ◽  
Carbonation Depth ◽  
Chloride Ion Penetration ◽  
Rebound Number ◽  
Ion Penetration

Permeable form can improve the quality of the surface layer of concrete and can enhance the durability of concrete structures. In this study, the improvement and its evaluation for the surface layer of concrete placed with permeable form were investigated. For these purposes, accelerated carbonation test, chloride ion penetration test, air permeability test, rebound hummer test and water permeability test were conducted using the concrete specimen. As a result, it was found that the air permeability correlates the carbonation depth, chloride ion penetration depth, rebound number and water permeable volume of concrete. Moreover, the possibility that the improvement for the surface layer of concrete can be quantitatively evaluated by air permeability test was shown.

scholarly journals The Influence of the Hybridization of Steel and Polyolefin Fiber on the Mechanical Properties of Base Concrete Designed for Marine Shotcreting Purposes

2021 ◽  
Vol 11 (20) ◽  
pp. 9456
Author(s):  
Changjoon Lee ◽  
Andres Salas Montoya ◽  
Hoon Moon ◽  
Hyunwook Kim ◽  
Chulwoo Chung
Keyword(s):  
Steel Fiber ◽  
Mechanical Performance ◽  
Synergetic Effect ◽  
Chloride Ion ◽  
Concrete Specimen ◽  
Hybrid Fiber ◽  
Electrically Conductive ◽  
Chloride Ion Penetration ◽  
Binder Ratio ◽  
Ion Penetration

The present study investigated the influence of the hybridization of steel and polyolefin fiber on the mechanical performance and chloride ion penetration of base concrete designed for marine shotcreting purposes. The purpose of fiber hybridization is to reduce the risk of corrosion that might occur during service life. Sets of hybrid fiber reinforced base concrete, whose water to binder ratio was 0.338, were prepared. The fiber contents in the base concrete were 0.54 and 1.08 vol%, and the volume proportion of polyolefin fiber in the hybrid fiber varied from 0 to 100%. Although the effect of fiber hybridization was not clearly observed from the compressive strength, a synergetic effect which increased both the flexural strength and toughness occurred at a fiber content of 1.08 vol%. The optimum ratio of steel and polyolefin fiber was 50:50. With respect to chloride ion penetration, an increasing amount of steel fiber increased the amount of current passing through the base concrete specimen due to the presence of electrically conductive steel fiber. However, chloride ion diffusivity was not greatly affected by the presence of steel fiber.

Penetration Behavior of Chloride Ions into Concrete in Coastal Areas

2006 ◽  
Vol 302-303 ◽  
pp. 584-590
Author(s):  
Yoshihiro Masuda ◽  
F.-R. Wu ◽  
S. Nakamura ◽  
S. Sato
Keyword(s):  
Chloride Ion ◽  
Concrete Specimen ◽  
Chloride Ions ◽  
Ion Content ◽  
Exposure Test ◽  
Total Chloride ◽  
Chloride Ion Penetration ◽  
Apparent Diffusion ◽  
Penetration Behavior ◽  
Ion Penetration

Exposure test on chloride ion penetration behavior into Concrete in coastal area was implemented. The distances between concrete specimens and coast were changed in the range from 50 to 150 meters, and water-cement ratios (W/C) were 45, 55, 60 and 65 %. The total chloride ion content at each different depth from surface of concrete specimen was measured at the age of 1, 2, 3, 5, 7, 8 and 10 years. In this paper, apparent diffusion coefficient (D) and chloride ion content on surface of concrete (C0) were calculated by inverse analyses from the measured total chloride ion content, and the chloride ion penetration behavior was simulated using the calculated D and C0. As a result, the chloride ion penetrated in concrete with a W/C of 60 % at a point 50 m from the sea for 10 years was estimated approximately 0.2 kg/m3.

Experimental Research on the Evaluation Method of the Resistance to Chloride Ion Penetration of Autoclaved PHC Pile

2014 ◽  
Vol 629-630 ◽  
pp. 587-592
Author(s):  
Yi Bo Yang ◽  
Zhao Qiong Lai ◽  
Li Tao Ai ◽  
Wen Ying Guo ◽  
Hong Jian Huang ◽  
...  
Keyword(s):  
Quality Control ◽  
Synthesis Method ◽  
Chloride Ion ◽  
Concrete Specimen ◽  
Life Assessment ◽  
Chloride Diffusion ◽  
Chloride Diffusion Coefficient ◽  
Chloride Ion Penetration ◽  
Chloride Migration ◽  
Ion Penetration

The usage of autoclaved PHC pile in chloride environment becomes common, so how to evaluate the resistance to chloride ion penetration of autoclaved PHC pile becomes urgent. This article Compare the resistance to chloride ion penetration of pile and pile concrete specimens based the Rapid Chloride Migration Synthesis Method and RCM. The results show that the Rapid Chloride Migration Synthesis Method is not suitable for pile, RCPT and RCM are suitable for pile; the resistance to chloride ion penetration of the pile inner and outer lateral concrete has a rather large different, so the sample must distinguish the direction when testing. Steel bar has little influence on the resistance to chloride ion penetration of autoclaved PHC pile, and the resistance to chloride ion penetration of pile outer lateral concrete is similar with pile concrete specimen, using pile concrete specimen to test the resistance to chloride ion penetration of autoclaved PHC pile is suitable. The chloride diffusion coefficient values have a good relationship with the electricity value, using the electricity value of square pile concrete specimen as commonly quality control way are suggested. The resistance to chloride ion penetration of pile can test the outer lateral concrete of pile or pile head, using the electricity value as daily quality control method and basis for project acceptance, and using RCM method as life assessment and basis for project acceptance.

scholarly journals Prediction of Chloride Ion Penetration of Recycled Aggregate Concrete

2015 ◽  
Vol 18 (2) ◽  
pp. 427-440 ◽  
Author(s):  
Rui Vasco Silva ◽  
Jorge de Brito ◽  
Rui Neves ◽  
Ravindra Dhir
Keyword(s):  
Chloride Ion ◽  
Recycled Aggregate Concrete ◽  
Recycled Aggregate ◽  
Aggregate Concrete ◽  
Chloride Ion Penetration ◽  
Ion Penetration

The Chloride Ion Penetration Model Coupled with Temperature and Moisture Transfer in Marine Environment

2012 ◽  
Vol 591-593 ◽  
pp. 2422-2427
Author(s):  
Juan Zhao
Keyword(s):  
Marine Environment ◽  
Moisture Transfer ◽  
Regional Climate ◽  
Chloride Ion ◽  
Chloride Penetration ◽  
Chloride Diffusion ◽  
Tidal Zone ◽  
Analog Simulation ◽  
Chloride Ion Penetration ◽  
Ion Penetration

Considering the complexity of the chloride ion penetration in concrete exposed to marine environment, an integrated chloride penetration model coupled with temperature and moisture transfer is proposed. The governing equations and parameters embody fully the cross-impacts among thermal conduction, moisture transfer and chloride ion penetration. Furthermore, the four exposure conditions are classified based on the different contact with the aggressive marine environment, and then the micro-climate condition on the concrete surface is investigated according to the regional climate characteristics, therefore, a comprehensive analog simulation to the chloride penetration process is proposed. To demonstrate that the proposed numerical model can correctly simulate the chloride diffusion in concrete, the integrated chloride diffusion model is applied in reproducing a real experiment, finally the model gives good agreement with the experimental profiles, and it is proved the tidal zone exposure results in a more severe attack on the reinforcement

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