scholarly journals Efficiency of Different Electrolytes on Electrochemical Chloride Extraction to Recover Concrete Structures under Chloride-Induced Corrosion

2020 ◽  
Vol 2020 ◽  
pp. 1-11
Author(s):  
Thamara Tofeti Lima ◽  
Ki Yong Ann
Keyword(s):  
Calcium Hydroxide ◽  
Tap Water ◽  
Corrosion Damage ◽  
Experimental Results ◽  
Optimal Decision ◽  
Cement Matrix ◽  
Lithium Borate ◽  
Concrete Deterioration ◽  
Chloride Induced Corrosion ◽  
Electrochemical Chloride Extraction

Chloride-induced corrosion is one of the main causes of concrete deterioration and imposes a challenge to sustainability. Traditional techniques to repair corroded structures consisted of basically removing the damaged area, which was either economical or sustainable. Therefore, electrochemical chloride extraction (ECE) gained popularity for being an efficient nondestructive treatment applied temporarily to structures. On this line, this manuscript aims to raise the efficiency of ECE by an optimal decision of the treatment setup concerning the electrolyte choice. Three different electrolytes were tested, namely, tap water, calcium hydroxide, and lithium borate. Experimental results pointed to lithium borate as the most efficient electrolyte for extracting chlorides while calcium hydroxide was a better choice to repassivate the structure and even heal cracks, due to a possible electrodeposition of the electrolyte ions on the cement matrix. Thus, depending on the main goal of the treatment, different electrolytes achieve a better performance, which highlights the importance of pretreatment evaluation to see in which stage of corrosion damage is the structure.

scholarly journals Three doors anomaly, “should I stay, or should I go”: an artefactual field experiment

2021 ◽  
Author(s):  
Andrea Morone ◽  
Rocco Caferra ◽  
Alessia Casamassima ◽  
Alessandro Cascavilla ◽  
Paola Tiranzoni
Keyword(s):  
Field Experiment ◽  
Experimental Evidence ◽  
Bayesian Updating ◽  
Anomalous Behavior ◽  
Status Quo ◽  
Experimental Results ◽  
Illusion Of Control ◽  
Optimal Decision ◽  
Status Quo Bias ◽  
The Impact

AbstractThis work aims to identify and quantify the biases behind the anomalous behavior of people when they deal with the Three Doors dilemma, which is a really simple but counterintuitive game. Carrying out an artefactual field experiment and proposing eight different treatments to isolate the anomalies, we provide new interesting experimental evidence on the reasons why subjects fail to take the optimal decision. According to the experimental results, we are able to quantify the size and the impact of three main biases that explain the anomalous behavior of participants: Bayesian updating, illusion of control and status quo bias.

scholarly journals Experimental results of a 10 kW high temperature thermochemical storage reactor based on calcium hydroxide

2014 ◽  
Vol 62 (2) ◽  
pp. 553-559 ◽  
Author(s):  
Matthias Schmidt ◽  
Christoph Szczukowski ◽  
Christian Roßkopf ◽  
Marc Linder ◽  
Antje Wörner
Keyword(s):  
High Temperature ◽  
Calcium Hydroxide ◽  
Experimental Results

scholarly journals Prevention of Chloride-induced Corrosion Damage to Bridges.

2002 ◽  
Vol 42 (12) ◽  
pp. 1376-1385 ◽  
Author(s):  
S. D. Cramer ◽  
B. S. Covino, Jr. ◽  
S. J. Bullard ◽  
G. R. Holcomb ◽  
J. H. Russell ◽  
...  
Keyword(s):  
Corrosion Damage ◽  
Chloride Induced Corrosion

Effects of Single and Compound Electrolyte Electrolyzed Cathode Waters on Mechanical Property and Hydration Reaction of Concrete

2020 ◽  
Vol 12 (3) ◽  
pp. 366-375
Author(s):  
Liang Wang ◽  
Hongzhu Quan
Keyword(s):  
Mechanical Property ◽  
Calcium Hydroxide ◽  
Tap Water ◽  
Small Extent ◽  
Hydration Reaction ◽  
Growth Ratio ◽  
Electrolyzed Water ◽  
Ordinary Concrete ◽  
Porosity Reduction ◽  
Strength Improvement

In this study, two kinds of different electrolyzed cathode water were used to prepare the concrete, the effects on mechanical property and hydration reaction of concrete were determined ultimately. Taking the influence of air-entraining admixture into consideration, the blank control test was also conducted. The experiment results showed that the single and compound electrolyte electrolyzed water both can effectively improve the strength of ordinary concrete, and the differences in strength between these two kinds of electrolyzed water concrete were not significant. To a small extent, the air-entraining admixtures would affect the activity of electrolyzed water and decrease the growth ratio of strength due to resistance effect. TG/DTA results test showed the calcium hydroxide amount of electrolyzed water concrete was obviously higher than that of natural tap water concrete at each age. In other words, the electrolyzed water in concrete can promote and boost the hydration reaction to produce more C–S–H gels and calcium hydroxide, leading to strength improvement and porosity reduction of concrete. In addition, the influence of the reaction between CO2–3 ions in electrolyzed water and calcium hydroxide on the increase of strength was little.

Microbubble Spectra and Superheat in Water and Sodium, Including Effect of Fast Neutron Irradiation

1976 ◽  
Vol 98 (1) ◽  
pp. 87-94 ◽  
Author(s):  
J. J. Pyun ◽  
F. G. Hammitt ◽  
A. Keller
Keyword(s):  
Tensile Strength ◽  
Numerical Solution ◽  
Fast Neutron ◽  
Neutron Irradiation ◽  
Tap Water ◽  
Experimental Results ◽  
Experimental Result ◽  
Diffusion Effect ◽  
Fast Neutron Irradiation ◽  
Increasing Temperature

The microbubble spectrum in a sample of tap water was measured by the Coulter counter technique under various conditions, and at the same time the tensile strength (i.e., “superheat” capacity) of the tap water was measured by the ultrasonic cavitation technique. It was observed in this experiment that the microbubble population and size increased and the superheat decreased for increasing temperature and under fast neutron irradiation. Finally the generalized Noltingk-Neppiras equation was solved numerically for selected initial microbubble radii, and the suppression pressure (or superheat) determined by this numerical solution was compared with the experimental result. Apparent inconsistencies in experimental results may be primarily due to the neglect of the rectified diffusion effect in the present analysis.

The Phase Transformation of Recycling Concrete in Recalcination

2013 ◽  
Vol 743-744 ◽  
pp. 175-179 ◽  
Author(s):  
Zhi Gang Zhang ◽  
Zong Hui Zhou ◽  
De Cheng Zhang ◽  
Xin Cheng
Keyword(s):  
Phase Transformation ◽  
Calcium Hydroxide ◽  
Calcium Silicate ◽  
Calcium Silicate Hydrate ◽  
Eutectic Temperature ◽  
Experimental Results ◽  
Industrial Wastes ◽  
Cement Clinker ◽  
Temperature Range ◽  
Natural Aggregates

In this paper, the artificial aggregates were prepared by limestone and industrial wastes in accordance with the ratio of cement raw meal, to obtain the recycling concrete replacing natural aggregates. Cement clinker could be regenerated by these recycling concrete and the aim of recycling could be realized. After these concrete was cured for 90 days, then was crushed and grinded, the phase transformation of recycling concrete in recalcination would been studied by XRD and so on. The experimental results showed that the composition of the recycling concrete met the demand of clinker modulus and C2S, C3S, C4AF, C3A were well crystallized at 1400 °C. So these recycling concrete could be directly calcined. The calcium hydroxide dehydrated around the temperature of 500°C. The calcium silicate hydrate was dehydrated gradually between the temperature of 400°C and 1000°C. At the same time, C2S crystallized during the temperature range. C4AF and C3A stared to crystallize around the temperature of 1000°C. Due to the composition of these concrete was complex, the lowest eutectic temperature dropped. C3S started to crystallize around the temperature of 1250°C and the best crystallization was achieved at the temperature of 1400°C.

Fatigue Testing of Welded Flat Head Pressure Vessel Joints

2007 ◽  
Author(s):  
Chris Hinnant
Keyword(s):  
Fatigue Testing ◽  
Tap Water ◽  
Fatigue Behavior ◽  
Plate Thickness ◽  
Fatigue Tests ◽  
Design Methods ◽  
Experimental Results ◽  
Testing Environment ◽  
Head Pressure ◽  
Thickness Testing

Experimental results for the fatigue testing of several welded flat head geometries are reported. These tests are similar to those previously reported by Hinnant (2006) [1] and focus on the fatigue behavior of full penetration welds with cover fillet welds. Fatigue calculations according to several fatigue design methods are compared against the experimental results, as are the mean fatigue curves of several of the design methods. Of particular interest for these new tests is the effect of plate thickness, testing environment, and geometric effects. Nominal plate thickness values ranging from 0.0625" (1.59 mm) to 0.1875" (4.76 mm) have been tested and correlated. Four additional fatigue tests were conducted using air to determine if previous testing in room temperature tap water resulted in decreased fatigue life.

CFD Modelling and Validation of Newtonian and Non-Newtonian Fluids in Curved Conduits

2015 ◽  
Vol 786 ◽  
pp. 181-187
Author(s):  
Abdulrahman Yousif ◽  
Azuraien Japper-Jaafar
Keyword(s):  
Pressure Drop ◽  
Drag Reduction ◽  
Reynolds Stress ◽  
Tap Water ◽  
Newtonian Fluids ◽  
Experimental Results ◽  
Polymer Additives ◽  
Centrifugal Forces ◽  
Cfd Modelling

CFD modelling of drag reduction agents (also called Flow Improvers) polymer additives dissolved in a newtonian solvent (UTP tap Water) was carried out in a curved conduit, A 7 equation Reynolds stress set of equations was used to simulate this flow. The purpose of this simulation is validate experimental results that show unusual pressure drop behaviour. CFD experiments show that there is pressure build-up near the end of the curved conduit due to severe centrifugal forces produced by the fluid, confirming the validity of the experimental results.

Crack Self-Healing Properties of Concrete with Adhesive

2014 ◽  
Vol 919-921 ◽  
pp. 1880-1884 ◽  
Author(s):  
Qing Yu Cao ◽  
Ting Yu Hao ◽  
Bo Su
Keyword(s):  
Flexural Strength ◽  
Vinyl Acetate ◽  
Ethylene Vinyl Acetate ◽  
Experimental Results ◽  
Experimental Program ◽  
Cement Matrix ◽  
Self Healing ◽  
Repair Efficiency ◽  
Healing Agent ◽  
Strength And Toughness

An experimental program was carried out to investigate whether EVA (ethylene vinyl acetate) heat-melt adhesive can potentially act as a self-healing agent in cement-based material. The effects of incorporation of EVA and heating on the properties of mortar were studied. Experimental results show that the interface between EVA and cement matrix was well improved after heating, which allows a significant improvement in flexural strength and toughness of specimen; Pre-damaged specimens in various degrees (30%, 50% and 70%) were effectively repaired by EVA and the repair efficiency all exceeded 100%. Keywords:crack; heat-melt adhesive; self-repairing

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