Chloride Penetration in Reinforced Concrete Structures: Case Study of Arvoredos Island

2021 ◽  
pp. 19-31
Author(s):  
Carlos Eduardo Tino Balestra
Keyword(s):  
Reinforced Concrete ◽  
Concrete Structures ◽  
Chloride Penetration ◽  
Reinforced Concrete Structures

Nanoparticle Injection into Concrete Using Electromigration

2014 ◽  
Vol 1054 ◽  
pp. 6-10 ◽  
Author(s):  
Jiří Němeček ◽  
Yun Ping Xi
Keyword(s):  
Reinforced Concrete ◽  
Electric Field ◽  
Concrete Structures ◽  
Chloride Penetration ◽  
Reinforced Concrete Structures ◽  
Testing Chamber ◽  
Chloride Profile ◽  
Nanosilica Particles ◽  
Penetration Tests ◽  
Small Voltage

This paper aims at investigation of possibilities and effectiveness of chloride extraction from concrete and nanoparticle injection into existing reinforced concrete structures by means of electromigration technique. Concrete specimens are exposed to accelerated chloride penetration tests in order to simulate a natural chloride exposure. The developed chloride profile is removed by electroextraction by reversing the polarity in the testing chamber. In a similar manner, concrete specimens are injected with different concentrations of colloidal nanosilica particles. It was shown in the paper that chlorides can be effectively extracted from the concrete using small voltage lasting for several days. Higher concentration solutions of nanosilica can also be effectively transported into concrete via the electric field. Once injected nanosilica can act as microstructure densifier and further reduce chloride penetration as demonstrated by decreased diffusivity of the treated concrete.

Use of Thermoplastic Polymer in Mortar Composites to Improve its Chloride Penetration Resistance

2016 ◽  
Vol 22 ◽  
pp. 33-44 ◽  
Author(s):  
M. Omrane ◽  
A.S. Benosman ◽  
M. Mouli ◽  
Y. Senhadji
Keyword(s):  
Reinforced Concrete ◽  
Flexural Strength ◽  
Portland Cement ◽  
Penetration Depth ◽  
Concrete Structures ◽  
Chloride Ion ◽  
Chloride Penetration ◽  
Partial Replacement ◽  
Total Charge ◽  
Reinforced Concrete Structures

This paper presents a study of the resistance to chloride penetration of blended Portland cement mortar containing thermoplastic waste polymer polyethylene terephthalate (TWPET). Composite TWPET-mortars are often presented as the materials of the future in reason of their potential for innovation and advantages that offer. In fact, the use of TWPET percentages as a cement substitution reduces energy costs; address problems related to environmental pollution by CO2 emissions and repairs various reinforced concrete structures. Blended Portland cement (CPJ) is partially replaced with TWPET at the amounts of 2%, 4% and 6% by weight of cementitious materials. Chloride penetration depth of full and partial immersions in 3% NaCl solution, rapid chloride permeability test (RCPT) after 28, 90 and 120 days, sorptivity, leaching test and flexural strength of thermoplastic-mortar composites (TMCs) were determined. Test results reveal that the resistance to chloride penetration of TMCs improves substantially with partial replacement of CPJ with TWPET and without significantly affecting the flexural strength in tap water. The chemical resistance is higher with an increase in the replacement level. So, sorptivity, the chloride ion penetration depth, apparent chloride ion diffusion coefficient, the total charge passed in coulombs and leached depth measurements of the TMCs are much smaller than those of reference mortar. The formations which appear such as different calcium salts were determined by X-ray diffraction. These results take into account the use of waste plastics in the manufacture of mortars modified which can be both recommended for preventing the chloride-induced corrosion of the steel in various reinforced concrete structures and participate greatly in the environment preservation.

scholarly journals The Effect of Water Repellent Surface Impregnation on Durability of Cement-Based Materials

2017 ◽  
Vol 2017 ◽  
pp. 1-9 ◽  
Author(s):  
Peng Zhang ◽  
Huaishuai Shang ◽  
Dongshuai Hou ◽  
Siyao Guo ◽  
Tiejun Zhao
Keyword(s):  
Reinforced Concrete ◽  
Service Life ◽  
Concrete Structures ◽  
Chloride Penetration ◽  
Water Repellent ◽  
Reinforced Concrete Structures ◽  
Capillary Suction ◽  
Surface Impregnation ◽  
Cement Based Materials ◽  
Ft Ir

In many cases, service life of reinforced concrete structures is severely limited by chloride penetration until the steel reinforcement or by carbonation of the covercrete. Water repellent treatment on the surfaces of cement-based materials has often been considered to protect concrete from these deteriorations. In this paper, three types of water repellent agents have been applied on the surface of concrete specimens. Penetration profiles of silicon resin in treated concrete have been determined by FT-IR spectroscopy. Water capillary suction, chloride penetration, carbonation, and reinforcement corrosion in both surface impregnated and untreated specimens have been measured. Results indicate that surface impregnation reduced the coefficient of capillary suction of concrete substantially. An efficient chloride barrier can be established by deep impregnation. Water repellent surface impregnation by silanes also can make the process of carbonation action slow. In addition, it also has been concluded that surface impregnation can provide effective corrosion protection to reinforcing steel in concrete with migrating chloride. The improvement of durability and extension of service life for reinforced concrete structures, therefore, can be expected through the applications of appropriate water repellent surface impregnation.

scholarly journals Analysis of Chloride Penetration Into High Performance Concrete

2020 ◽  
Vol 3 (3) ◽  
pp. 295-305
Author(s):  
Silvija Mrakovčić ◽  
Natalija Bede ◽  
Ivan Ušić
Keyword(s):  
Reinforced Concrete ◽  
High Performance ◽  
High Performance Concrete ◽  
Concrete Structures ◽  
Chloride Penetration ◽  
Reinforced Concrete Structures ◽  
Wetting And Drying ◽  
Chloride Corrosion ◽  
Structure Degradation ◽  
Astm C1202

Corrosion of reinforcement is one of basic destruction mechanisms of reinforced concrete structures. In that sense, the most affected structures are those by the sea, especially their parts subjected to cycles of wetting and drying. Chlorides penetrate to concrete mostly by diffusion, faster if the concrete is more permeable, destructing reinforcement passive protection and causing its corrosion, reduction of reinforcement cross section and bearing capacity of the structure. Retardation of chloride corrosion that causes structure degradation in marine environment can be achieved by the usage of quality concrete with enhanced strength and permeability parameters in regards to ordinary concrete. Mixes of ordinary and high performance concrete with different ratio of silica fume have been made. Compressive strength and resistivity to chloride penetration have been tested on the specimens 28 days after mixing. The resistivity to chloride penetration has been determined by fast chloride penetration test according to ASTM C1202 standard, using appliance that measures electrical conductivity of concrete specimens. Based on test results, the suitability of building reinforced concrete structures by the sea using high performance concrete has been analysed.

scholarly journals Effect of addition JORPHOS to Self-Compacting Concrete for Chloride Penetration

2016 ◽  
Vol 5 (2) ◽  
pp. 1
Author(s):  
Mahmoud B. Alhasanat ◽  
Arabi N. S. Al Qadi ◽  
Loai A. Al Tarabulsi ◽  
Omar A. Al khashman
Keyword(s):  
Reinforced Concrete ◽  
Concrete Structures ◽  
Chloride Penetration ◽  
Harsh Environments ◽  
Reinforced Concrete Structures ◽  
Permeability Test ◽  
Self Compacting Concrete ◽  
Chloride Permeability ◽  
Maintenance And Repair ◽  
Repair Costs

<p class="1Body">Reinforced concrete structures are exposed to harsh environments, yet they are often expected to last with little or no repair or maintenance for long periods of time (often 100 years or more). For this reason, a durable structure needs to be produced. In addition, bridge reinforced concrete suffering from attacks of chloride penetration that cause corrosion of the steel in the reinforcement concrete that leads to reduction in strength and serviceability cracking, which cause further repair and rehabilitation for the structure and greater maintenance and repair costs. This research focuses on self-compacting concrete with Jordanian Phosphate (JORPHOS) as a filler. The permeability for different percentages of JORPHOS were tested by using Rapid Chloride Permeability Test (RCPT). It was concluded that the addition of different percentages of JORPHOS minimizes chloride penetration in concrete.</p>

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