Alkali-silica reaction (ASR) is a chemical reaction that occurs in some concrete mixtures and causes premature deterioration. It can be prevented by including a supplementary cementitious material (SCM) in the concrete mix design. Research has found that finely ground pumice from Idaho is highly effective at mitigating ASR. When used as a partial replacement for cement, pumice consumes excess calcium hydroxide to prevent alkali-silica gel formation, reduces concrete pH levels, and densifies the matrix to block moisture infiltration and expansion of any remaining gel. Pumice-blended cement allows for use of local aggregates, increases durability, and mitigates ASR for a low cost
Flatline the alkali-silica reaction (ASR) in concrete using pumice-blended cement…at a cost of just pennies per yard. Quantifiable performance backed by ASTM-standard research.
Research Summary: How Pumice Pozzolan Improves Concrete Strength and DurabilityHess Pumice Products
A landmark research study done by the University of Utah details how pumice pozzolans improve concrete strength and durability by mitigating or eliminating the problems that plague standard concrete. Adding natural pumice pozzolan to the concrete mix design ignites a pozzolanic reaction in the curing concrete that defeats deleterious effects like heat of hydration cracking, sulfate and chloride attacks, freeze-thaw spalling, alkali silica reaction (ASR), and efflorescence. Long-term compressive strength is increased anywhere from 10 to 40 percent.
The basic components of cement mortar are cement, water and aggregates. But, often, other substances are added to these three in preparing the cement mortar. The purpose of these additional substances is to improve the quality of the mortar. These substances are collectively called admixtures. Admixtures can be broadly classified into two types – chemical admixtures and mineral admixtures.
Flatline the alkali-silica reaction (ASR) in concrete using pumice-blended cement…at a cost of just pennies per yard. Quantifiable performance backed by ASTM-standard research.
Research Summary: How Pumice Pozzolan Improves Concrete Strength and DurabilityHess Pumice Products
A landmark research study done by the University of Utah details how pumice pozzolans improve concrete strength and durability by mitigating or eliminating the problems that plague standard concrete. Adding natural pumice pozzolan to the concrete mix design ignites a pozzolanic reaction in the curing concrete that defeats deleterious effects like heat of hydration cracking, sulfate and chloride attacks, freeze-thaw spalling, alkali silica reaction (ASR), and efflorescence. Long-term compressive strength is increased anywhere from 10 to 40 percent.
The basic components of cement mortar are cement, water and aggregates. But, often, other substances are added to these three in preparing the cement mortar. The purpose of these additional substances is to improve the quality of the mortar. These substances are collectively called admixtures. Admixtures can be broadly classified into two types – chemical admixtures and mineral admixtures.
11 mechanisms of corrosion of structural concrete and how to stop themMichael Aldred
There are ONLY 11 mechanisms of corrosion of reinforced structural concrete. There is only ONE common denominator of the cause of all 11 mechanisms. This presentation demonstrates these facts. This presentation demonstrates the ONLY time proven way to STOP all 11 mechanisms, for the life of the concrete
The potential of rice husk ash in concreteShaswat K. Das
The main objective of this paper is to study Rice Husk Ash (RHA), it’s property and potential to be used both as partial and full replacement of cement in concrete production. As the RHA is a pozzolanic material containing about 85-90% of silicon dioxide (SiO2), it has the potential to be used as a supplementary cementitious material (SCM) in conventional cement concrete as well as a source material in Geopolymer concrete. This paper presents a precise overview of work carried out on RHA by various scientists and researchers both in cement concrete and Geopolymer concrete.
Keywords- Rice Husk Ash, Geopolymer, Pozzolanic material, supplementary cementitious material
for the literature follow the link-https://drive.google.com/open?id=1m8mpAMXFvzineLrAAKRayFoS1E1hRW3r
International Journal of Engineering Research and DevelopmentIJERD Editor
Electrical, Electronics and Computer Engineering,
Information Engineering and Technology,
Mechanical, Industrial and Manufacturing Engineering,
Automation and Mechatronics Engineering,
Material and Chemical Engineering,
Civil and Architecture Engineering,
Biotechnology and Bio Engineering,
Environmental Engineering,
Petroleum and Mining Engineering,
Marine and Agriculture engineering,
Aerospace Engineering.
EFFECT OF SELF - CURING ON MECHANICAL CHARACTERISTIC OF SELF-COMPACTING CONCR...IAEME Publication
In this Research Study, the Use of Super Absorbent Polymer (SAP) and Polyethylene glycol as Self curing agents in concrete is proven to have many positive effects on the properties of concrete in its both stages; Fresh and hardened concrete. The function of Self- curing agents is to reduce the water evaporation from concrete. The use of Self Curing admixtures is very important from the point of view that saving of water is a necessarily everyday (each one cubic metre of concrete requires 3m3 of water in construction, most of water consumed is for curing, Hence it is necessary to reduce the use of water in construction and save water). The Present research work focuses on use of Polyethylene glycol (PEG) and Super Absorbent Polymer (SAP) as self-curing agents, affect of Self Curing Concrete agents on Mechanical Characteristics Using Msand, and compared with those of conventionally cured concrete. In this Study 0.1%, 0.2% and 0.3% SAP and 1%, 1.5% and 2% PEG was varied for M25 grade of Concrete Mixes and Specimen. The experimental results show that, in general, the combined use of, 1.5%, 0.2% SAP in combination with Fly ash and Silica Fume as mineral admixture showed superior results in comparison to conventional curing method, enhancing the mechanical properties of SCC.
11 mechanisms of corrosion of structural concrete and how to stop themMichael Aldred
There are ONLY 11 mechanisms of corrosion of reinforced structural concrete. There is only ONE common denominator of the cause of all 11 mechanisms. This presentation demonstrates these facts. This presentation demonstrates the ONLY time proven way to STOP all 11 mechanisms, for the life of the concrete
The potential of rice husk ash in concreteShaswat K. Das
The main objective of this paper is to study Rice Husk Ash (RHA), it’s property and potential to be used both as partial and full replacement of cement in concrete production. As the RHA is a pozzolanic material containing about 85-90% of silicon dioxide (SiO2), it has the potential to be used as a supplementary cementitious material (SCM) in conventional cement concrete as well as a source material in Geopolymer concrete. This paper presents a precise overview of work carried out on RHA by various scientists and researchers both in cement concrete and Geopolymer concrete.
Keywords- Rice Husk Ash, Geopolymer, Pozzolanic material, supplementary cementitious material
for the literature follow the link-https://drive.google.com/open?id=1m8mpAMXFvzineLrAAKRayFoS1E1hRW3r
International Journal of Engineering Research and DevelopmentIJERD Editor
Electrical, Electronics and Computer Engineering,
Information Engineering and Technology,
Mechanical, Industrial and Manufacturing Engineering,
Automation and Mechatronics Engineering,
Material and Chemical Engineering,
Civil and Architecture Engineering,
Biotechnology and Bio Engineering,
Environmental Engineering,
Petroleum and Mining Engineering,
Marine and Agriculture engineering,
Aerospace Engineering.
EFFECT OF SELF - CURING ON MECHANICAL CHARACTERISTIC OF SELF-COMPACTING CONCR...IAEME Publication
In this Research Study, the Use of Super Absorbent Polymer (SAP) and Polyethylene glycol as Self curing agents in concrete is proven to have many positive effects on the properties of concrete in its both stages; Fresh and hardened concrete. The function of Self- curing agents is to reduce the water evaporation from concrete. The use of Self Curing admixtures is very important from the point of view that saving of water is a necessarily everyday (each one cubic metre of concrete requires 3m3 of water in construction, most of water consumed is for curing, Hence it is necessary to reduce the use of water in construction and save water). The Present research work focuses on use of Polyethylene glycol (PEG) and Super Absorbent Polymer (SAP) as self-curing agents, affect of Self Curing Concrete agents on Mechanical Characteristics Using Msand, and compared with those of conventionally cured concrete. In this Study 0.1%, 0.2% and 0.3% SAP and 1%, 1.5% and 2% PEG was varied for M25 grade of Concrete Mixes and Specimen. The experimental results show that, in general, the combined use of, 1.5%, 0.2% SAP in combination with Fly ash and Silica Fume as mineral admixture showed superior results in comparison to conventional curing method, enhancing the mechanical properties of SCC.
UNDERSTANDING AND MITIGATING DOWNHOLE CORROSION AND WEAR FAILURES westernfalcontx
A discussion on different types of corrosion and wear (and their associated mechanisms) followed by an overview of commercially available mitigation techniques, including their practical downhole applications are the focal points of this paper.
Knowledge brief detailing the advantages and function of pumice as a soil amendment and conditioner. SoilRox is a brand name for select pumice grades for use in preparing potting soils, garden soil, and even large-scale landscaping and reclamation efforts when poor native soil needs improvement—especially structurally (as in the case with heavy clay soils)—to support vibrant plant life.
Pumice-based scrubs and soaps exfoliate without needing help from chemistry...or a lot of elbow grease, as a light-touch scrubbing is all that is needed for the microscopic surfaces of the pumice grit to do the job.
As a filtration media, pumice is an aggressively-filtering alternative to sand (and other filtration media). The low specic gravity and high porosity of pumice make it ideal for irrigation filtration systems and other water treatment processes and provides several advantages over other filtration media such as sand, expanded clay, and anthracite.
Is Hess pumice the right "scrub" ingredient for your exfoliative product? That can only be answered definitively at the other end of your careful evaluation and testing process, but we can tell you that Hess pumice comfortably meets these key consideration criteria: Proven, Sustainable, Cost Effective, Eco-friendly, Ideal Structure, and Naturally Pure and White.
Puzolana de pumita: Resumen de la segunda fase del estudio sobre la cuantific...Hess Pumice Products
Concreto resistente a la reacción álcali-sílice con mezcla de cemento con plumita: Informe desarrollado por el Laboratorio de Investigación y Evaluación de Materiales y Concretos del Departamento de Ingeniería Civil y Ambiental de la Universidad de Utah
Una vez que la reacción química álcali-sílice (ASR) comienza a deteriorar el concreto no hay manera de detenerla. ¿La solución? Mitigar la reacción álcali-sílice con la mezcla de cemento y piedra pómez.
Publication covers typical uses for economical cementitious grout in a variety of large- and small-scale civil and commercial construction projects, including specific uses within these broad categories: soil stabilization, groundwater control, soil strengthening, and sealing fissures in rock and concrete structures.
Technical data sheet for a uniquely formulated cementitious grout that combines ultrafine particle size (average 3 micron), a pozzolanic charge for enduring strength and density, and a variable-dosage liquid super-plasticizer that expands the geologic effectiveness range of the grout.
As the U.S. Green Building Council’s Leadership in Energy and Environmental Design (LEED) certification program grows and evolves, so too does the need to understand the fit of a wide range of effective materials and processes to meet LEED certification requirements. As product use alone does not provide LEED points, the information in this just-released white paper focuses on identifying the LEED categories and options where pumice and pumice-enhanced products from Hess Pumice can be valuable contributors to the goal of LEED certification.
Graph—Geologic Effectiveness of Grouts for Soil StabilizationHess Pumice Products
U.S. Grout Ultrafine VX is a uniquely formulated cementitious grout that combines ultrafine particle size (average 3 micron), a pozzolanic charge for enduring strength and density, and a liquid super-plasticizer (USG-Super) that amplifies the fine-soil permeating rheology of the grout, allowing it to penetrate deeply and permeate completely the pore spaces in even fine-grained soils.
Key Excerpts from Research Study Done on a Unique Ultrafine Cementitious GroutHess Pumice Products
Atomic Energy Canada LLC (AECL) was commissioned to optimize and verify the physical parameters of an ultrafine pozzolanic cementitious grout developed by Sandia National Laboratories for the U.S. Department of Energy. Key excerpts from that research report are reprinted in this slide deck.
US Grout manufactures Ultrafine and Microfine Cementitious Grouts. Made from Portland cement, pumice, and super-plasticizers, US Grouts are super-charged with natural pumice pozzolan, effectively overcoming the deleterious effects inherent in standard cementitious grouts. US Grout Ultrafine, with an average particle size of 3 microns, will effectively penetrate and seal micro fractures and completely grout dense silty soils. These are truly superior cementitious grouts that have effective application for sealing microfractures in rock, “squeeze” cementing in the petroleum industry, repairing concrete structures, improving the bearing capacity of weak soils, and limiting the migration of contaminants in environmental remediation.
Democratizing Fuzzing at Scale by Abhishek Aryaabh.arya
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Cosmetic shop management system project report.pdfKamal Acharya
Buying new cosmetic products is difficult. It can even be scary for those who have sensitive skin and are prone to skin trouble. The information needed to alleviate this problem is on the back of each product, but it's thought to interpret those ingredient lists unless you have a background in chemistry.
Instead of buying and hoping for the best, we can use data science to help us predict which products may be good fits for us. It includes various function programs to do the above mentioned tasks.
Data file handling has been effectively used in the program.
The automated cosmetic shop management system should deal with the automation of general workflow and administration process of the shop. The main processes of the system focus on customer's request where the system is able to search the most appropriate products and deliver it to the customers. It should help the employees to quickly identify the list of cosmetic product that have reached the minimum quantity and also keep a track of expired date for each cosmetic product. It should help the employees to find the rack number in which the product is placed.It is also Faster and more efficient way.
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Hybrid optimization of pumped hydro system and solar- Engr. Abdul-Azeez.pdffxintegritypublishin
Advancements in technology unveil a myriad of electrical and electronic breakthroughs geared towards efficiently harnessing limited resources to meet human energy demands. The optimization of hybrid solar PV panels and pumped hydro energy supply systems plays a pivotal role in utilizing natural resources effectively. This initiative not only benefits humanity but also fosters environmental sustainability. The study investigated the design optimization of these hybrid systems, focusing on understanding solar radiation patterns, identifying geographical influences on solar radiation, formulating a mathematical model for system optimization, and determining the optimal configuration of PV panels and pumped hydro storage. Through a comparative analysis approach and eight weeks of data collection, the study addressed key research questions related to solar radiation patterns and optimal system design. The findings highlighted regions with heightened solar radiation levels, showcasing substantial potential for power generation and emphasizing the system's efficiency. Optimizing system design significantly boosted power generation, promoted renewable energy utilization, and enhanced energy storage capacity. The study underscored the benefits of optimizing hybrid solar PV panels and pumped hydro energy supply systems for sustainable energy usage. Optimizing the design of solar PV panels and pumped hydro energy supply systems as examined across diverse climatic conditions in a developing country, not only enhances power generation but also improves the integration of renewable energy sources and boosts energy storage capacities, particularly beneficial for less economically prosperous regions. Additionally, the study provides valuable insights for advancing energy research in economically viable areas. Recommendations included conducting site-specific assessments, utilizing advanced modeling tools, implementing regular maintenance protocols, and enhancing communication among system components.
COLLEGE BUS MANAGEMENT SYSTEM PROJECT REPORT.pdfKamal Acharya
The College Bus Management system is completely developed by Visual Basic .NET Version. The application is connect with most secured database language MS SQL Server. The application is develop by using best combination of front-end and back-end languages. The application is totally design like flat user interface. This flat user interface is more attractive user interface in 2017. The application is gives more important to the system functionality. The application is to manage the student’s details, driver’s details, bus details, bus route details, bus fees details and more. The application has only one unit for admin. The admin can manage the entire application. The admin can login into the application by using username and password of the admin. The application is develop for big and small colleges. It is more user friendly for non-computer person. Even they can easily learn how to manage the application within hours. The application is more secure by the admin. The system will give an effective output for the VB.Net and SQL Server given as input to the system. The compiled java program given as input to the system, after scanning the program will generate different reports. The application generates the report for users. The admin can view and download the report of the data. The application deliver the excel format reports. Because, excel formatted reports is very easy to understand the income and expense of the college bus. This application is mainly develop for windows operating system users. In 2017, 73% of people enterprises are using windows operating system. So the application will easily install for all the windows operating system users. The application-developed size is very low. The application consumes very low space in disk. Therefore, the user can allocate very minimum local disk space for this application.
Explore the innovative world of trenchless pipe repair with our comprehensive guide, "The Benefits and Techniques of Trenchless Pipe Repair." This document delves into the modern methods of repairing underground pipes without the need for extensive excavation, highlighting the numerous advantages and the latest techniques used in the industry.
Learn about the cost savings, reduced environmental impact, and minimal disruption associated with trenchless technology. Discover detailed explanations of popular techniques such as pipe bursting, cured-in-place pipe (CIPP) lining, and directional drilling. Understand how these methods can be applied to various types of infrastructure, from residential plumbing to large-scale municipal systems.
Ideal for homeowners, contractors, engineers, and anyone interested in modern plumbing solutions, this guide provides valuable insights into why trenchless pipe repair is becoming the preferred choice for pipe rehabilitation. Stay informed about the latest advancements and best practices in the field.
Vaccine management system project report documentation..pdfKamal Acharya
The Division of Vaccine and Immunization is facing increasing difficulty monitoring vaccines and other commodities distribution once they have been distributed from the national stores. With the introduction of new vaccines, more challenges have been anticipated with this additions posing serious threat to the already over strained vaccine supply chain system in Kenya.
Saudi Arabia stands as a titan in the global energy landscape, renowned for its abundant oil and gas resources. It's the largest exporter of petroleum and holds some of the world's most significant reserves. Let's delve into the top 10 oil and gas projects shaping Saudi Arabia's energy future in 2024.
White Paper: Flatline Alkali-Silica Reaction with Pumice-Blended Cement
1. IN REGIONS OF THE WORLD with reactive
aggregate, Alkali-Silica Reaction (ASR) is a relentless
infrastructure assassin. If the seeds of ASR—reactive
aggregate and Portland-cement-spawned calcium
hydroxide (CH)—are present in cured concrete, that
concrete structure will not survive to the end of its
engineered lifespan. On most lists that bullet-point
top contributors to premature concrete failure, ASR is
second only to corrosion of reinforcing steel. The
irony in that one-two list relationship is the fact that
W H I T E P A P E R
Flatline Alkali-Silica Reaction
with Pumice-BlendedCement
forPennies aYard There is no way to stop ASR
once such chemically-flawed
concrete has been placed.
The solution? Mitigate it in
the concrete mix design.
EXECUTIVE SUMMARY
In regions with reactive aggregate, the alkali-silica
reaction (ASR) is a pestilence that infects and destroys
vital concrete infrastructure. ASR fuels a relentless,
slow-motion explosion that shatters both the
concrete and the aggregate, significantly shortening
the engineered lifespan of the infected structure.
Once the alkali-silica reaction kindles within
concrete—triggered by the collision of alkali, silica,
moisture, and calcium hydroxide (a deleterious
byproduct spawned by the Portland cement+ water
hydration reaction)—it cannot be stopped. Failure is
imminent.
ASR must be mitigated in the concrete mix
design by specifying a consistent, quantifiable
supplementary cementitious material (SCM) that
flatlines the reaction. Clean, naturally calcined
pumice from the massive Hess deposit in south-
east Idaho USA is ideal: this carefully refined
pumice not only delivers proven ASR mitigation in
the presence of even highly reactive aggregates, it
does so as a percentage of cement replacement
while contributing additional durability benefits to
the concrete as well.
When a specially ground superior grade pumice
(from the Hess Pumice deposit) is incorporated as an
SCM in the concrete mix design, the ASR problem
goes away—for just pennies a yard. Even better, the
mechanism that flatlines the alkali-silica reaction is
one that targets and reclaims deleterious calcium
hydrate (CH), converting it to CSH, the chemical
binder that makes concrete work.That both removes
the trouble-spawning CH from the hydrated concrete
paste and repurposes it to amplify the density and
strength of the concrete matrix.
ABOVE: ASR-damaged concrete
showing map-cracking and evidence
of ASR gel squeezing to surface.
LEFT: Petrographic analysis micro-photo
of ASR-infected concrete core sample.
2. even mild ASR-fueled map-cracking accelerates the
chemical attacks on reinforcing steel.
ASR falls within the broader category of Alkali-
aggregate reaction (AAR) and is currently one of the
two types of recognized AAR reactions, depending on
the nature of the reactive mineral. The alkali-silica
reaction (ASR) involves various types of reactive silica
(SiO2) minerals; alkali-carbonate reaction (ACR)
involves certain types of dolomitic rocks
(CaMg(CO3)2). Both types of reaction can result in
expansion and cracking of concrete, leading to a
reduction in the service life of concrete structures.
Researchers have defined a causal triangle that sets
off the chemical ASR train wreck within concrete. The
merger of water, Portland cement, and reactive aggre-
gate generate the four essential ingredients of expansive
ASR gel—alkalis, silica, free calcium hydroxide (CH),
and moisture. Starving the concrete of one of those
components can effectively flatline ASR.
The ASR Train Wreck Explained
Simple explanation: the alkali compounds within
Portland cement react with the silica in the aggregate
forming a chemical compound with a thirsty affinity for
water. As water is absorbed, the resulting gel swells,
cracking both concrete and aggregate, opening the
concrete to further attack from outside elements—
Flatline Alkali-Silica Reaction with Pumice | 2
sulfates and chlorides, marine salts, and freeze-thaw—
which accelerate the death-march of the structure.
Deep dive: the primary chemical reaction
(hydration) between Portland cement and water creates
a deleterious compound know as Calcium Hydroxide
(CH)—radical free calcium—that, unabated, reacts with
alkali and aggregate-contributed silica to form a hydro-
philic (water-attracting) gel that expands relentlessly.
The reaction will go dormant when starved of moisture,
only to swell and expand again when sufficient water is
again present.
In many cases, several concrete-destroying
mechanisms are acting together. Some of the deleterious
CH also migrates to the surface, leaving behind a porous
network of microscopic, inter-connected wormholes
that provide for easy ingress of water to continue to fuel
the expansive ASR gel. Free ingress of water also begins
the destructive freeze-thaw cycle. Chlorides and sulfates
also join the invasion, attacking the concrete and the
reinforcing steel within. As ASR-induced map-cracking
spreads to the surface, the death-march of the structure
is accelerated.
Once the alkali-silica reaction begins within placed
concrete, it cannot be stopped. Several methods are
effective in slowing it down—(various drying methods,
chemical treatments, stress relief, restraint)—but the
0 20 30 40 50 60
0.80
0.70
0.60
0.50
0.40
0.30
0.20
0.10
0.00
LENGTHCHANGE(%)
IMMERSION(Days)
A C C E P T A B L E L I M I T
100%
CEMENT
PUMICE
BLENDED
CEMENT
ASTMC1293(modified)
MITIGATING ASR WITH
PUMICE-BLENDED CEMENT
Concrete MixdesignstestedaccordingtoamodifiedASTMC1293procedure
usingType1cementandHighly Reactive coarseandfineaggregateinan
acceleratedASRenvironment(80°Cand1NNaOHsolution)over50days.
3. Flatline Alkali-Silica Reaction with Pumice | 3
hard facts are these: ASR-affected concrete is flawed at
the molecular level and will not reach its engineered
lifespan.
Defeating ASR
Where concrete engineers have had success
combating and defeating ASR is with preventative mix
designs. Various ineffective and often impractical
methods have been identified and used since the
alkali-silica reaction was first identified in the late
1930s, including using low-alkali cement, trucking in
non-reactive aggregate, specifying low W/C ratios,
using less cement, even air entrainment.
Until now, the most effective and practical
solutions involved using SCMs that in one way or
another disrupted the corruptive union of alkali, silica,
moisture, and CH. These SCMs included lithium
nitrate, Metakaolin, silica fume, flash-cooled furnace
slag, and a combination of low-alkali cement and
Class F fly ash.
Recent research, spurred by studies made on
enduring Roman concrete structures (many over 2000
years old), has centered on the use of pumice as an
excellent SCM for improving modern concrete perfor-
mance and lifespan. This historical evidence, combined
with current, quantifiable research, has also revealed
pumice to be a particularly effective mitigator of ASR.
ASR Miti•Gator™ is a natural pumice SCM mined
and refined from the Hess deposit in southeast Idaho:
the world’s purest commercial deposit of white pumice.
It’s a simple product with a complex chemical nature
that powers a chemical reaction within hydrated
concrete that flatlines the alkali-silica reaction.
The ASR Miti•Gator™ Advantage
University-level, ASTM-spec research into ASR
prevention conducted specifically using ASR
Miti•Gator™ has identified and defined the following
effectiveness mechanisms:
1 • ASR Miti•Gator™ directly consumes much of the
deleterious CH (a byproduct of the primary hydraulic
reaction), preventing the ionic interaction with the
alkali that forms thirsty alkali-silica gel. The fact that
ASR Miti•Gator is used as a percentage of replacement
for Portland cement also means less CH is spawned by
the primary hydraulic reaction.
2 • ASR Miti•Gator™ reduces the pH of the concrete
pore solution by entrapping free alkalis.
3 • The pozzolanic reaction ignited by introducing
finely-processed pumice to the concrete mix design
tightens the concrete matrix to block and control
moisture infiltration. What little alkali-silica gel that
may form is denied moisture and cannot swell.
4. 4 • The pozzolanic reaction provides for a denser,
stronger concrete that is more resistant to the expansive
pressure caused by any remaining ASR gel.
Beyond its ASR-stomping effectiveness at a molecular
level, ASR Miti•Gator provides additional advantages:
5 • The performance benefits of using natural
pumice in a concrete mix design go well beyond
defeating ASR. Heat of hydration is reduced and
compressive strength preserved. The pozzolanic
reaction densely welds the concrete matrix, significantly
amping resistance to sulfate and chloride attacks (per
ASTM C1012) while increasing abrasion resistance and
resisting freeze-thaw damage.
6 • Allows for use of standard Portland cement
(instead of low-alkali type) and locally-sourced aggre-
gate, reactive or otherwise.
7 • The consistent chemical makeup and perfor-
mance of ASR Miti•Gator is well-suited for cement
replacement (typically 20%), providing both a cost
advantage as well as additional benefits to concrete
performance and durability that go beyond simply
mitigating ASR.
8 • ASR Miti•Gator™ can be tightly optimized as a
cement replacement for specific reactive aggregates
once the properties of a given aggregate are known.
This can lead to the use of economical pumice-blended
cements for preventing not only ASR, but to solve other
concrete durability issues.
9 • ASR Miti•Gator™ is derived from a plentiful,
sustainable source. It is naturally calcined, naturally free
of hazardous contaminants, and performs consistently
pour after pour.
ASR Miti•Gator’s alkali-silica mitigating properties,
cost-effective price-point as a cement replacement, and
quantifiable performance put destructive ASR clearly in
the crosshairs—new concrete structures can be effec-
tively free of ASR, no matter the aggregate source.
The Research
Beginning in 2012, the University of Utah began
research into the effectiveness of pumice as an
supplementary cementitious material (SCM) to
improve the short-lived durability of modern concrete.
Flatline Alkali-Silica Reaction with Pumice | 4
The durability of Roman concrete provided empirical
evidence that pumice (the original pozzolan) was an
excellent concrete performance booster, but quantifiable
research data was needed.
The results of that study not only quantified the
performance of naturally occurring pumice as an effec-
tive SCM, but revealed that pumice (in particular the
pumice mined and processed from the Hess Pumice
deposit) was an impressive mitigator of the alkali-silica
reaction. This in turn led to follow-up research into the
mechanisms and potency of pumice as a cost-effective
ASR-mitigating SCM.
Downloadable summaries of the research conducted
by the University of Utah (and others) can be found on
the ASR Miti•Gator website: www.asrmitigator.com
The Company Behind ASR Miti•Gator™
Hess Pumice Products of Malad, Idaho, is the world
leader in processed pumice mining, production, and
beneficiation. We ship hundreds of products to thou-
sands of customers across six continents for use in
multiple industrial and commercial processes—abrasion,
paints and coatings, turf management, soil conditioning
for reclamation and engineered landscapes, soilless
growing systems, filtration, lightweight aggregate,
cementitious grout, spill containment, cleansing exfoli-
ant, blast mitigation, finish plasters, and more—those in
addition to our concrete performance-boosting products.
—by Brian Jeppsen, VP-R&D at Hess Pumice Products
of Malad City, Idaho.
Telephone: 1.800.767.4701 x 111
Email: brian@hesspumice.com
Website: http://www.asrmitigator.com
University of Utah Research Summary:
http://www.asrmitigator.com/PDFs/downloads.html