Utilization of lithium nitrate to mitigate alkali–silica reaction of architectural glass mortar: Characteristics and mechanisms

2022 ◽  
Vol 315 ◽  
pp. 125433
Author(s):  
Ziming Deng
Keyword(s):  
Alkali Silica Reaction ◽  
Lithium Nitrate

New observations on the mechanism of lithium nitrate against alkali silica reaction (ASR)

2010 ◽  
Vol 40 (1) ◽  
pp. 94-101 ◽  
Author(s):  
X. Feng ◽  
M.D.A. Thomas ◽  
T.W. Bremner ◽  
K.J. Folliard ◽  
B. Fournier
Keyword(s):  
Alkali Silica Reaction ◽  
Lithium Nitrate

scholarly journals Effect of lithium nitrate on the reaction between opal aggregate and sodium and potassium hydroxides in concrete over a long period of time

2017 ◽  
Vol 65 (6) ◽  
pp. 773-778 ◽  
Author(s):  
J. Zapała-Sławeta ◽  
Z. Owsiak
Keyword(s):  
Electron Microscopy ◽  
Pore Solution ◽  
Alkali Silica Reaction ◽  
Lithium Nitrate ◽  
X Ray ◽  
Long Period ◽  
Chemical Admixtures ◽  
Mortar Bar ◽  
Sodium And Potassium ◽  
Scanning Electron

AbstractAlkali-silica reaction (ASR) is a reaction between amorphous or poorly crystallized siliceous phase, present in aggregates, and sodium and potassium hydroxides in the pore solution of concrete. Chemical admixtures such as lithium compounds are known to have high potential of inhibiting ASR. The aim of this study was to determine the effect of lithium nitrate on ASR in mortars containing high reactive opal aggregate over a long period of time. Mortar bar expansion tests were performed and microstructures of mortar bars were observed by scanning electron microscopy coupled with an energy dispersive X-ray microanalyser. Results from this study showed that effectiveness of lithium nitrate in mitigating ASR was limited over a long period of time. A larger amount of ASR gel which was formed in the presence of lithium nitrate indicated that the deterioration processes intensify within longer periods of time, which so far has not been observed in literature. Microscopic observation confirmed the presence of alkali-silica gel and delayed ettringite in mortars with lithium nitrate.

scholarly journals The use of lithium salts and supplementary cementing materials to control reactivity of recycled concrete aggregate

2021 ◽  
Author(s):  
Waleed Mikhaiel
Keyword(s):  
Preventive Measure ◽  
Calcium Content ◽  
Recycled Concrete ◽  
Alkali Silica Reaction ◽  
Alkaline Solutions ◽  
Concrete Aggregate ◽  
Second Phase ◽  
Lithium Nitrate ◽  
Recycled Concrete Aggregate ◽  
Supplementary Cementing Materials

This thesis covered the second phase of a study that focused on the reactivity of recycled concrete aggregate (RCA) produced from concrete affected by alkali-silica reaction (ASR). The first phase investigated the reactivity of ASR-affected RCA and the use of Supplementary Cementing Materials (SCM) as a preventive measure. The second phase was carried out to study the efficacy of lithium nitrate, when used individually and in combination with SCM, in suppressing the reactivity of RCA. The use of different dosages of lithium nitrate combined with SCMs reduced expansion due to ASR. However, the expansion results showed that increasing the dosage of lithium beyond a certain level does not help in suppressing the expansion. The high reacitivity of the tested RCA was attiributable to its relatively high alkalis and calcium hydroxide contents that fuel further ASR. The alkalis consumed or contributed from RCA were evaluated through leaching the aggregate particles in distilled water and alkaline solutions at different molarities with and without lithium nitrate. Alkalis consumption was found to decrease when lithium was presented in the leaching solutions. Examining RCA samples under scanning electron microscope (SEM) showed that the crushing process of the RCA exposes fresh surfaces of the reactive virgin aggregate and creates cracks within the particles that provide an easy path of alkalis to reactive sites within the RCA. Examination of the composition of ASR gel showed that exposing the RCA to lithium solution decreased the calcium content and Ca/Si of the gel. This could add to the suggested mechanisms by which the lithium mitigates ASR.

scholarly journals Effect of Lithium Nitrate on the Alkali-Silica Reaction Gel

2008 ◽  
Vol 91 (10) ◽  
pp. 3370-3374 ◽  
Author(s):  
José F. Schneider ◽  
Nicole P. Hasparyk ◽  
Denise A. Silva ◽  
Paulo J. M. Monteiro
Keyword(s):  
Alkali Silica Reaction ◽  
Lithium Nitrate

scholarly journals The use of lithium salts and supplementary cementing materials to control reactivity of recycled concrete aggregate

2021 ◽  
Author(s):  
Waleed Mikhaiel
Keyword(s):  
Preventive Measure ◽  
Calcium Content ◽  
Recycled Concrete ◽  
Alkali Silica Reaction ◽  
Alkaline Solutions ◽  
Concrete Aggregate ◽  
Second Phase ◽  
Lithium Nitrate ◽  
Recycled Concrete Aggregate ◽  
Supplementary Cementing Materials

This thesis covered the second phase of a study that focused on the reactivity of recycled concrete aggregate (RCA) produced from concrete affected by alkali-silica reaction (ASR). The first phase investigated the reactivity of ASR-affected RCA and the use of Supplementary Cementing Materials (SCM) as a preventive measure. The second phase was carried out to study the efficacy of lithium nitrate, when used individually and in combination with SCM, in suppressing the reactivity of RCA. The use of different dosages of lithium nitrate combined with SCMs reduced expansion due to ASR. However, the expansion results showed that increasing the dosage of lithium beyond a certain level does not help in suppressing the expansion. The high reacitivity of the tested RCA was attiributable to its relatively high alkalis and calcium hydroxide contents that fuel further ASR. The alkalis consumed or contributed from RCA were evaluated through leaching the aggregate particles in distilled water and alkaline solutions at different molarities with and without lithium nitrate. Alkalis consumption was found to decrease when lithium was presented in the leaching solutions. Examining RCA samples under scanning electron microscope (SEM) showed that the crushing process of the RCA exposes fresh surfaces of the reactive virgin aggregate and creates cracks within the particles that provide an easy path of alkalis to reactive sites within the RCA. Examination of the composition of ASR gel showed that exposing the RCA to lithium solution decreased the calcium content and Ca/Si of the gel. This could add to the suggested mechanisms by which the lithium mitigates ASR.

scholarly journals Effect of Lithium Based Admixtures on Alkali Silica Reaction in Concrete and Flexural Behavior of Reinforced Concrete Rectangular Beams

2018 ◽  
Vol 7 (1) ◽  
pp. 52-59
Author(s):  
S. Sathya .
Keyword(s):  
Mechanical Properties ◽  
Reinforced Concrete ◽  
Lithium Ion Batteries ◽  
Electronic Waste ◽  
Great Influence ◽  
Lithium Ion ◽  
Flexural Behavior ◽  
Alkali Silica Reaction ◽  
Lithium Nitrate ◽  
Gel Formation

In recycling of lithium-ion batteries, lithium is a challenging element, which possesses great threat to the environment. The disposal of electronic waste is a major problem, which our country is currently facing, whereas, the lithium is one of the compound in electronic waste which challenges the recycling of lithium-ion batteries. If lithium is properly extracted, it can be used for structural engineering purpose. Lithium, if used in concrete, it controls the cracks due to alkali silica reaction (ASR), resulting in increased strength and durability of the concrete. Lithium based admixtures are effective in suppression of alkali silica reaction and delayed ettringite formation, if the dosage added in concrete is appropriate. The main objective of this paper is to assess the effectiveness of LiNO3 at various dosage levels in concrete. In this paper, the effect of LiNO3 on the mechanical properties of concrete, ASR gel formation and the flexural behavior of reinforced concrete rectangular beams are studied. The mechanical properties of concrete was investigated for six mix proportions comprising of control mix, lithium nitrate at 0.6M, 0.65M, 0.7M, 0.75M, 0.8M. LiNO3 not only prevents the ASR gel formation, but also it has great influence on mechanical properties of concrete. The results indicate that the concrete with 0.75M LiNO3 has higher strength values. SEM analysis has been performed for 0.75M and control mix to study the micro characteristics of concrete. The ASR gel formed in 0.75M has been suppressed as compared to that of concrete without lithium nitrate as an admixture. The durability studies are performed in concrete for water permeability, water absorption and rapid chloride penetration characteristics. The analytical study of flexural behavior of reinforced concrete rectangular beam is done using the software ANSYS 16.0.

Prevention of Alkali-Silica Reaction (ASR) in Light-Weight Wellbore Cement Comprising Silicate-Based Microspheres

2017 ◽  
Author(s):  
Dylan Albers ◽  
Mileva Radonjic
Keyword(s):  
Alkali Silica Reaction ◽  
Lithium Nitrate ◽  
Light Weight ◽  
Lost Circulation ◽  
Chemical Instability ◽  
Alkali Silica Reactivity ◽  
High Alkalinity ◽  
Hydrophilic Gel ◽  
Micro Indentation ◽  
Scanning Electron

Drilling through low pressure formations, either offshore or through depleted formations, requires the use of low density fluids to prevent lost circulation and as well as to properly place cement during cementing applications. Achieving these densities in cements can be done through foaming the cement, increasing water content, or through the addition of silica based microspheres. Each of these methods have individual limitations, and in the case of silica based microspheres, their specific fallback is a chemical instability with the microsphere itself reacting with the cement pore fluid. This chemical instability creates a hydrophilic gel that is expansive and creates fractures in the cement as it expands, which is more formally referred to as alkali-silica reactivity (ASR). Prevention of ASR involves the application of additives to the cement that acts as a sink for the alkalinity in which prevents the expansion of ASR. A specific application that this paper investigates for this prevention is the use of Lithium nitrate. This study looks at the effects of a high alkalinity environment onto the microspheres by visualizing the reactions that are occurring using Scanning Electron Microscopy (SEM), and confirming the presence of ASR when silica based microspheres encounter a high pH environment. Then cement samples were created to compare the effects lithium nitrate has on cements created with silica based microspheres. SEM and micro indentation was conducted on these samples, which showed that lithium nitrate prevents reactions, but after 28-day hydration a loss of mechanical properties is present.

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