Mechanisms of chemical degradation of cement-based systems

proceedings of the Material Research Society"s Symposium on Mechanisms of Chemical Degradation of Cement-based Systems, Boston, USA, 27-30 November 1995 by Symposium on Mechanisms of Chemical Degradation of Cement-based Systems (1995 Boston, Mass.)

Publisher: E & FN Spon in London, New York

Written in English
Cover of: Mechanisms of chemical degradation of cement-based systems | Symposium on Mechanisms of Chemical Degradation of Cement-based Systems (1995 Boston, Mass.)
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Subjects:

  • Concrete -- Corrosion -- Congresses.,
  • Concrete construction -- Deterioration -- Congresses.,
  • Concrete -- Chemical resistance -- Congresses.

Edition Notes

Includes bibliographical references and index.

Statementedited by K.L. Scrivener and J.F. Young.
ContributionsScrivener, K. L., Young, J. Francis., Materials Research Society.
Classifications
LC ClassificationsTA445 .S87 1995
The Physical Object
Paginationix, 455 p. :
Number of Pages455
ID Numbers
Open LibraryOL771471M
ISBN 100419215700
LC Control Number97171051

This book examines Physical, chemical, and mechanical processes involved in the degradation mechanisms of concrete and steel structures located in severe environments; Methods and strategies for life-cycle design and assessment of deteriorating structural systems under uncertainty;. Perhaps the most common causes of materials degradation are chemically mediated since they can proceed without the expenditure of mechanical work. It is an unfortunate reality that technology currently relies on metals in a reduced or unoxidized state while under terrestrial conditions; the oxidized state represents chemical equilibrium. Recently, there is ongoing interest in the use of natural plant fibers as alternatives for conventional reinforcements in cementitious composites. The use of natural plant fibers makes engineering work more sustainable, since they are renewable, biodegradable, energy-efficient, and non-toxic raw materials. In this contribution, a comprehensive experimental program was undertaken to determine.   Geothermal environments are among the most difficult conditions for cements to survive. Normally accepted for high-temperature oil wells silica-modified Portland-based cement formulations are not durable in hostile geothermal environments failing to provide good zonal isolation and metal casing corrosion-protection. High-temperature well cement compositions based on calcium-aluminate .

M olecular degradation is a leading cause of plastic component failure, with a study indicating that 17% of plastic failures are associated with a degradation mechanism. 1 In generic terms, molecular degradation of a plastic is the deleterious alteration of the molecular structure within the polymer as the result of a chemical reaction. ACIDIC CORROSION OF HYDRATED CEMENT BASED MATERIALS PART 1. - MECHANISM OF THE PHENOMENON ALI ALLAHVERDI, FRANTIŠEK ŠKVÁRA Institute of chemical technology, Department of glass and ceramics, Technická 5, 28 Prague 6, Czech Republic E-mail: [email protected] Submitted January 3, ; accepted May 9, Chemical oxidation using peracetic acid (PAA) can be enhanced by activation with the formation of reactive species such as organic radicals (R–O•) and HO•. Thermal activation is an alternative way for PAA activation, which was first applied to degrade micropollutants in this study. PAA is easily decomposed by heat via both radical and nonradical pathways. Our experimental results suggest.   Chemical Degradation Methods for Wastes and Pollutants focuses on established and emerging chemical procedures for the management of pollutants in industrial wastewater and the environment. This reference offers an in-depth explanation of the degradation process, mechanisms, and control factors affecting each method, as well as issues crucial to thReviews: 1.

  Cement systems for CO 2 sequestration. Secondary cementing is done to seal off the wells used to inject CO 2 in the reservoir. A good well cement should have an appropriate thickening time, a good rheology, a low water loss efficiency, and no free water bleeding (Lesti et al. ).There are eight classes of cements listed in the American Petroleum Institute (API) Footnote 1 standard. structures having high degree of thermal resistance, there is loss in mechanical properties and durability when they are exposed to extremely high temperatures. This research aims to improve the understanding of complex mechanisms that drive thermal degradation of cement-based composite materials. The complexity of this system is that it requires combined experimental, theoretical, and modeling approaches to elucidate the characteristics of the individual reactions, and their mutual interaction. In this review, we describe recent results from quantum chemical and theoretical kinetic studies of relevance to atmospheric chemistry. Microbial biodegradation is the use of bioremediation and biotransformation methods to harness the naturally occurring ability of microbial xenobiotic metabolism to degrade, transform or accumulate environmental pollutants, including hydrocarbons (e.g. oil), polychlorinated biphenyls (PCBs), polyaromatic hydrocarbons (PAHs), heterocyclic compounds (such as pyridine or quinoline.

Mechanisms of chemical degradation of cement-based systems by Symposium on Mechanisms of Chemical Degradation of Cement-based Systems (1995 Boston, Mass.) Download PDF EPUB FB2

Mechanisms of Chemical Degradation of Cement-based Systems book. DOI link for Mechanisms of Chemical Degradation of Cement-based Systems.

Mechanisms of Chemical Degradation of Cement-based Systems book. Edited By K.L. Scrivener, J.F. Young. Edition 1st Edition. First Published Cited by: Title: MCDCS: Mechanisms of Chemical Degradation of Cement-based Systems Author(s): K.L. Scrivener & J.F.

Young Publication: Technical Documents Volume: Issue: Appears on pages(s): Keywords: Date: 1/1/ Abstract: Deterioration of cement-based materials is a continuing problem, as it results in the substantial shortening of the lives of conventional concrete structures.

The degradation mechanisms and kinetics induced on the cement based matrix were compared to those obtained with the reference, acetic acid, which has been thoroughly studied in the literature.

Portland cement pastes were exposed to acid Cited by:   Buy Mechanisms of Chemical Degradation of Cement-based Systems 1 by K.L. Scrivener, J.F. Young (ISBN: ) from Amazon's Book Store. Everyday low prices and free delivery on eligible orders. There is a wide range of materials degradation mechanisms but all can be classified into four basic categories: (i) by direct mechanical action, (ii) by heat or radiation, (iii) by the presence of chemical reagents and (iv) where two or more of (i), (ii) and (iii) combine synergistically.

In Mechanism of Chemical Degradation of Cement Based Systems. Edited by Scrivener KL, Young JF London: E&FN Spon; Crammond NJ and Halliwell MA: Assessment of the conditions required for the thaumasite form of sulfate attack.

In Mechanism of Chemical Degradation of Cement Based Systems. For the first time, this article reviews the literature both on mechanisms by which this chemical degradation of the ionomer membrane occurs and the sites on the polymer susceptible to free radical attack, as well as how this learning and increased understanding have been used to build and develop successful mitigation strategies designed to.

In biological systems, degradation of bioceramics reflects nonequilibrium processes that occur simultaneously or in competition with each other.

Because bioceramics alone are not used in load-bearing conditions, the mechanical degradation mechanism will not be addressed in this chapter. Physico-Chemical Degradation of Bioceramics. Chemical degradation and depletion of the stabilizer system are the most obvious and most serious changes that occur.

Most of the research work on recovery of recycled materials is focused on the two deficiencies. Other chemical and physical changes should not be ignored because they directly affect the processability and the properties of recycled products.

Targeting protein degradation using small molecules is one of the most exciting small-molecule therapeutic strategies in decades and a rapidly growing area of research. In particular, the development of proteolysis targeting chimera (PROTACs) as potential drugs capable of recruiting target proteins to the cellular quality control machinery for elimination has opened new avenues to address.

Strength, stiffness, and thermal properties as well as failure modes are affected by the mechanical and chemical degradation of composites (Greszczuk, ). Generally, stiffness, strength, and coefficients of thermal expansion decrease with increases in microcrack density.

Generally alkali-activated binders (AAB), like cement-based systems, exhibit good compressive but relatively poor tensile and flexural properties. Strength development of AAB depends on various influencing factors, such as types and properties of prime materials - solid precursors, as well as synthesis and curing conditions.

Mechanisms and Modelling of Waste / Cement Interactions xi SESSION 9 LEACH Chairs: H. van der Sloot (The Netherlands) and D. Jacques (Belgium) page ESTIMATES OF MINERAL STABILITY CONSTANTS DERIVED FROM PH DEPENDENCE LEACHING TEST DATA FOR GEOCHEMICAL MODELLING OF CEMENT-BASED WASTE SYSTEMS van der Sloot, H.

A. Reprint from Mechanisms of Chemical Degradation of Cement-based Systems (K.L. Scrivener and J.F. Young Eds.), Spon, London,pp. MICROSTRUCTURAL CHANGES OF HYDRATED CEMENT PASTE DUE.

The direct immobilization and destruction of two compounds relevant to chemical warfare agents, ethyl methylphosphonic acid (EMPA) and thiodiglycol (TDG), within a freshly mixed Portland cement paste was studied.

Cement hydration and phase formation were analyzed to determine the upper limits on the loading of these chemicals achievable in an immobilization setting. EMPA, a degradation product. Degradation (corrosion) of non-metallic building materials Chemical degradation, physical degradation, physical-chemical degradation, bio-corrosion Causes of corrosion and degradation – temperature changes, moisture effects, atmospheric effects, mechanical effects Degradation due to the water-soluble salts, salts sources.

In this regard, it is key to develop wide-range imaging systems, enabling accurate and spatially resolved determination of pH variability for an advanced knowledge of degradation mechanisms.

GeoProc collects the proceedings of the International Conference on Coupled T-H-M-C (thermal, hydraulic, mechanical, chemical) Processes in Geosystems. Slow chemical degradation processes such as calcium leaching alters the cement matrix mineralogy (due to dissolution of mineral phases) and consequently changes its transport and mechanical.

Numerical Simulation of the Effect of Elevated Temperature Curing on Porosity of Cement-based Systems, Mechanisms of Chemical Degradation of Cement-based Systems, /, (), (). Many disposal concepts currently show that concrete is an effective confinement material used in engineered barrier systems (EBS) at a number of low-level radioactive waste (LLW) disposal sites.

Cement-based materials have properties for the encapsulation, isolation, or retardation of a variety of hazardous contaminants. The reactive chemical transport model of HYDROGEOCHEM was.

A recent review of Glasser et al. [] discusses in detail the mechanisms that govern transport in cementitious systems and different chemical degradation phenomena including chloride ingress. Jedidi M, Benjeddou O () Chemical Causes of Concrete Degradation. MOJ Civil Eng 4(1): MOJ Civil Eng 4(1): DOI: /mojce A general approach to modelling chemical degradation processes in cement based materials, due to combined action of hygro-thermal, chemical and mechanical loads, is presented.

Mechanics of multiphase porous media and damage mechanics are applied for this purpose. Leaching involves a deterioration of many physical and mechanical properties of cement-based materials such as porosity, elastic modulus, compressive strength, internal friction angle and creep (Burlion et al.

; Haga et al. b; Constantinides and Ulm ; Bernard et al. ; Heukamp et al. ; Stora et al. ; Sellier et al. This book provides a general holistic view of materials degradation without undue emphasis on aqueous corrosion with the neglect of other important topics such as liquid metal corrosion.

Discussion of materials degradation is balanced by detailed description and evaluation of surface engineering as a means of managing materials degradation. However, this type of degradation is a combination of the in vivo chemical degradation with the presence of mechanical stresses.

In other words, polymer chain scission caused by the chemical degradation, create microscopic defects that are augmented by the presence of mechanical loads, leading to the formation of cracks on the surface (Wiggins.

Synthesis of [email protected] Core–Shell Nanoparticles with Tunable Shell Thickness and Their Degradation Mechanism in Aqueous Solutions. Langmuir36 (13), chemical groups of their composition and the magnitude of intra or intermolecular forces i.e primary and secondary valence bonds present in the polymer.

Degradation process occurs due to the influence of thermal, chemical, mechanical, radiative and biochemical factors. CdS-Decorated MIL(Fe) Microrods with Enhanced Visible Light Photocatalytic Performance for the Degradation of Ketorolac Tromethamine and Mechanism Insight.

The Journal of Physical Chemistry C(27). Influences and mechanisms of chemically synthesized nano-C-S-H gel addition on fresh properties of the cement-based materials with sucrose as a retarder were investigated in this study. The results showed that the flow value of the fresh cement paste was gradually but slightly reduced with increasing nano-C-S-H gel addition due to its fibrous but well-dispersed characteristic in both water and.This paper presents a review of the physical, chemical and biological pre-treatments that have been performed on natural fibers, their results and effects on the fiber–matrix interface of cement and geopolymer composites.

In addition, the degradation mechanisms of natural fibers used in such composites are discussed. Alkali–silica reaction (ASR) attack is one of the most significant durability concerns in cement-based materials.

In this paper, the drinking water treatment sludge (DWTS), which is a typical by-product from the drinking water treatment industry, was reused as supplementary cementitious material to mitigate the degradation of mortar resulting from ASR attack. DWTS was milled and .