Effects of Concrete Moisture on Polymer Overlay Bond Over New Concrete

Effects of Concrete Moisture on Polymer Overlay Bond Over New Concrete PDF Author: Andrew Joseph Shearrer
Publisher:
ISBN:
Category : Concrete
Languages : en
Pages : 200

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Book Description
Epoxy polymer overlays have been used for decades on existing bridge decks to protect the deck and extend its service life. The polymer overlay's ability to seal a bridge deck is now being specified for new construction. Questions exist about the amount of drying time needed to achieve an acceptable concrete moisture content to ensure an adequate bond to the polymer overlay. The 2007 Kansas Department of Transportation (KDOT) specifications for new bridge decks call for a 14-day wet curing period followed by 21 days of drying. If not enough drying is provided, the moisture within the concrete can form water vapor pressure at the overlay interface and induce delamination. If too much drying time is provided, projects are delayed, which can increase the total project cost or even delay overlay placement until the next spring. A testing procedure was developed to simulate a bridge deck in order to test the concrete moisture content and bonding strength of the overlay. Concrete slabs were cast to test typical concrete and curing conditions for a new bridge deck. Three concrete mixtures were tested to see what effect the water-cement ratio and the addition of fly ash might have on the overlay bond strength. Wet curing occurred at three different temperatures (40 degrees F, 73 degrees F, and 100 degrees F) to see if temperature played a part in the bond strength as well. The concrete was then allowed to dry for 3, 7, 14, or 21 days. Five epoxy-polymer overlay systems that had been preapproved by KDOT were each used in conjunction with the previously mentioned concrete and curing conditions. After this, the slabs were setup to perform pull-off tests to test the tensile rupture strength. The concrete slabs with the different epoxy overlays were heated to 122-125 degrees F to replicate summer bridge deck temperatures. Half of the pull-off tests were performed when the slabs were heated and half were performed once the slabs had cooled back down to 73 degrees F plus or minus 5 degrees F. Results from the pull-off tests as well as results from a moisture meter taken on the concrete prior to the overlay placement were compared and analyzed. Testing conditions were compared with each other to see which had a larger effect on the epoxy polymer overlay's bond strength. The results showed that concrete bridge deck polymer overlays could be placed sooner than 21 days after concrete placement and still have an adequate bond.

Effects of Concrete Moisture on Polymer Overlay Bond Over New Concrete

Effects of Concrete Moisture on Polymer Overlay Bond Over New Concrete PDF Author: Andrew Joseph Shearrer
Publisher:
ISBN:
Category : Concrete
Languages : en
Pages : 200

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Book Description
Epoxy polymer overlays have been used for decades on existing bridge decks to protect the deck and extend its service life. The polymer overlay's ability to seal a bridge deck is now being specified for new construction. Questions exist about the amount of drying time needed to achieve an acceptable concrete moisture content to ensure an adequate bond to the polymer overlay. The 2007 Kansas Department of Transportation (KDOT) specifications for new bridge decks call for a 14-day wet curing period followed by 21 days of drying. If not enough drying is provided, the moisture within the concrete can form water vapor pressure at the overlay interface and induce delamination. If too much drying time is provided, projects are delayed, which can increase the total project cost or even delay overlay placement until the next spring. A testing procedure was developed to simulate a bridge deck in order to test the concrete moisture content and bonding strength of the overlay. Concrete slabs were cast to test typical concrete and curing conditions for a new bridge deck. Three concrete mixtures were tested to see what effect the water-cement ratio and the addition of fly ash might have on the overlay bond strength. Wet curing occurred at three different temperatures (40 degrees F, 73 degrees F, and 100 degrees F) to see if temperature played a part in the bond strength as well. The concrete was then allowed to dry for 3, 7, 14, or 21 days. Five epoxy-polymer overlay systems that had been preapproved by KDOT were each used in conjunction with the previously mentioned concrete and curing conditions. After this, the slabs were setup to perform pull-off tests to test the tensile rupture strength. The concrete slabs with the different epoxy overlays were heated to 122-125 degrees F to replicate summer bridge deck temperatures. Half of the pull-off tests were performed when the slabs were heated and half were performed once the slabs had cooled back down to 73 degrees F plus or minus 5 degrees F. Results from the pull-off tests as well as results from a moisture meter taken on the concrete prior to the overlay placement were compared and analyzed. Testing conditions were compared with each other to see which had a larger effect on the epoxy polymer overlay's bond strength. The results showed that concrete bridge deck polymer overlays could be placed sooner than 21 days after concrete placement and still have an adequate bond.

Maintenance, Safety, Risk, Management and Life-Cycle Performance of Bridges

Maintenance, Safety, Risk, Management and Life-Cycle Performance of Bridges PDF Author: Nigel Powers
Publisher: CRC Press
ISBN: 1351745972
Category : Technology & Engineering
Languages : en
Pages : 550

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Book Description
Maintenance, Safety, Risk, Management and Life-Cycle Performance of Bridges contains lectures and papers presented at the Ninth International Conference on Bridge Maintenance, Safety and Management (IABMAS 2018), held in Melbourne, Australia, 9-13 July 2018. This volume consists of a book of extended abstracts and a USB card containing the full papers of 393 contributions presented at IABMAS 2018, including the T.Y. Lin Lecture, 10 Keynote Lectures, and 382 technical papers from 40 countries. The contributions presented at IABMAS 2018 deal with the state of the art as well as emerging concepts and innovative applications related to the main aspects of bridge maintenance, safety, risk, management and life-cycle performance. Major topics include: new design methods, bridge codes, heavy vehicle and load models, bridge management systems, prediction of future traffic models, service life prediction, residual service life, sustainability and life-cycle assessments, maintenance strategies, bridge diagnostics, health monitoring, non-destructive testing, field testing, safety and serviceability, assessment and evaluation, damage identification, deterioration modelling, repair and retrofitting strategies, bridge reliability, fatigue and corrosion, extreme loads, advanced experimental simulations, and advanced computer simulations, among others. This volume provides both an up-to-date overview of the field of bridge engineering and significant contributions to the process of more rational decision-making on bridge maintenance, safety, risk, management and life-cycle performance of bridges for the purpose of enhancing the welfare of society. The Editors hope that these Proceedings will serve as a valuable reference to all concerned with bridge structure and infrastructure systems, including students, researchers and engineers from all areas of bridge engineering.

Environmental Influence on the Bond Between a Polymer Concrete Overlay and an Aluminum Substrate

Environmental Influence on the Bond Between a Polymer Concrete Overlay and an Aluminum Substrate PDF Author: David W. Mokarem
Publisher:
ISBN:
Category : Concrete bridges
Languages : en
Pages : 29

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Book Description
Chloride-ion-induced corrosion of reinforcing steel in concrete bridge decks has become a major problem in the United States. Latex-modified concrete, low-slump dense concrete, and hot-mix asphalt membrane overlays are some of the most used rehabilitation methods. Epoxy-coated reinforcing steel was developed and promoted as a long-term corrosion protection method by the Federal Highway Administration. However, recent evidence has suggested that epoxy-coated reinforcing steel will not provide adequate long-term corrosion protection. The Reynolds Metals Company developed an aluminum bridge deck system as a proposed alternative to conventional reinforced steel bridge deck systems. The deck consists of a polymer concrete overlay and an aluminum substrate. The purpose of this investigation was to evaluate the bond durability between the overlay and the aluminum substrate after specimens were conditioned in various temperature and humidity conditions. The different environmental conditionings all had a significant effect on the bond durability. Specimens conditioned at 30°C, 45 °C, and 60°C at 98 percent relative humidity all showed a decrease in interfacial bond strength after conditioning. There was also a decrease in the interfacial bond strength for the specimens conditioned in freezing and thawing cycles and specimens conditioned in a salt water soak. The only exposure condition that increased the bond strength was drying the specimens continuously in an oven at 60°C.

Polymers in Concrete

Polymers in Concrete PDF Author: Y. Ohama
Publisher: CRC Press
ISBN: 1482271826
Category : Architecture
Languages : en
Pages : 554

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Book Description
Increasing attention is being given to the use of concrete-polymer composites as high performance and multi-functional materials in the construction industry, as well as in mechanical, electrical and chemical engineering. Particular interest is being given to these materials in Japan and other East Asian countries. This book forms the proceedings o

Polymer Concrete Overlay Test Program

Polymer Concrete Overlay Test Program PDF Author: Oregon. State Highway Division
Publisher:
ISBN:
Category : Polymer-impregnated concrete
Languages : en
Pages : 30

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Book Description
This report describes work done on various combinations of monomers and polymer concrete mixes and identifies the mixes showing the greatest potential for use in bridge deck overlays. Presented are test results showing physical properties of various polymer concrete mixes, such as compressive strength, split tensile strength, modulus of elasticity, thermal coefficient of expansion, and shrinkage coefficient. The effects of polymer content, work time, and temperature on various properties are also discussed. The development of two polymer concrete systems with excellent membrane potential are described along with the details of bonding characteristics of several systems. Finally, a polymer concrete mix with suitable properties for deck and pavement patching is detailed.

In-place Performance of Polymer Concrete Overlays

In-place Performance of Polymer Concrete Overlays PDF Author: Stella Marusin
Publisher:
ISBN:
Category : Concrete bridges
Languages : en
Pages : 216

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Book Description


Applications of Polymer Concrete

Applications of Polymer Concrete PDF Author: David W. Fowler
Publisher:
ISBN:
Category : Technology & Engineering
Languages : en
Pages : 222

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Book Description


Polymers in Concrete

Polymers in Concrete PDF Author: Peter Mendis
Publisher:
ISBN:
Category : Technology & Engineering
Languages : en
Pages : 228

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Book Description


Failure, Distress and Repair of Concrete Structures

Failure, Distress and Repair of Concrete Structures PDF Author: Norb Delatte
Publisher: Elsevier
ISBN: 1845697030
Category : Technology & Engineering
Languages : en
Pages : 352

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Book Description
Understanding and recognising failure mechanisms in concrete is a fundamental pre-requisite to determining the type of repair, or whether a repair is feasible. This title provides a review of concrete deterioration and damage, as well as looking at the problem of defects in concrete. It also discusses condition assessment and repair techniques. Part one discusses failure mechanisms in concrete and covers topics such as causes and mechanisms of deterioration in reinforced concrete, types of damage in concrete structures, types and causes of cracking and condition assessment of concrete structures. Part two reviews the repair of concrete structures with coverage of themes such as standards and guidelines for repairing concrete structures, methods of crack repair, repair materials, bonded concrete overlays, repairing and retrofitting concrete structures with fiber-reinforced polymers, patching deteriorated concrete structures and durability of repaired concrete. With its distinguished editor and international team of contributors, Failure and repair of concrete structures is a standard reference for civil engineers, architects and anyone working in the construction sector, as well as those concerned with ensuring the safety of concrete structures. Provides a review of concrete deterioration and damage Discusses condition assessment and repair techniques, standards and guidelines

REPAIR AND REHABILITATION OF CONCRETE STRUCTURES

REPAIR AND REHABILITATION OF CONCRETE STRUCTURES PDF Author: MODI, POONAM I.
Publisher: PHI Learning Pvt. Ltd.
ISBN: 8120352149
Category : Technology & Engineering
Languages : en
Pages : 198

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Book Description
The field of Concrete Repair and Rehabilitation is gaining importance in view of its positive impacts in terms of socio-economic benefits and environmental sustainability. Due to growing importance of this field, many engineering colleges have included the subject of concrete repair and rehabilitation in the senior undergraduate and postgraduate course curriculums of civil engineering. This book is an earnest attempt to help students of civil engineering in enhancing their understanding and awareness about critical elements of repair and rehabilitation of concrete structure. The content is organised in such a way that it fulfils the academic needs of the students. This text attempts to dovetail all important aspects such as causes of distress, assessment and evaluation of deterioration, techniques for repair and rehabilitation along with selection of repair and rehabilitation materials and other important aspects related to preventive maintenance and rehabilitation/structural safety measures. The primary objective of this textbook is to guide students to: • Understand the underlying causes and types of deterioration in concrete structure • Learn about the field and laboratory testing methods available to evaluate the level of deterioration. • Get well acquainted with options of repair materials and techniques available to address different types of distress in concrete structure. • Grasp the knowledge of available techniques and their application for strengthening existing structural systems.