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2019 | Buch

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Thermal Cracking of Massive Concrete Structures

State of the Art Report of the RILEM Technical Committee 254-CMS

herausgegeben von: Dr. Eduardo M.R. Fairbairn, Miguel Azenha

Verlag: Springer International Publishing

Buchreihe : RILEM State-of-the-Art Reports

Enthalten in: Springer Professional "Wirtschaft+Technik" , Springer Professional "Technik" , Springer Professional "Wirtschaft"

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Über dieses Buch

This book provides a State of the Art Report (STAR) produced by RILEM Technical Committee 254-CMS ‘Thermal Cracking of Mas-sive Concrete Structures’. Several recent developments related to the old problem of understanding/predicting stresses originated from the evolution of the hydration of concrete are at the origin of the creation this technical committee. Having identified a lack in the organization of up-to-date scientific and technological knowledge about cracking induced by hydration heat effects, this STAR aims to provide both practitioners and scientists with a deep integrated overview of consolidated knowledge, together with recent developments on this subject.

Inhaltsverzeichnis

Frontmatter

Chapter 1. Introduction

Abstract

This chapter provides an introduction to the State of the Art Report (STAR) produced by RILEM Technical Committee 254-CMS ‘Thermal Cracking of Massive Concrete Structures’. Several recent developments related to the old problem of understanding/predicting stresses originated from the evolution of the hydration of the concrete are at the origin of the creation of this technical committee. Having identified that there was a lack in the organization of up-to-date scientific and technological knowledge about cracking induced by hydration heat effects, it was decided to establish this STAR. It aims to provide both practitioners and scientists with a deep integrated overview of consolidated knowledge, together with recent developments on this subject.

Eduardo M. R. Fairbairn, Miguel Azenha

Chapter 2. Hydration and Heat Development

Abstract

The driving process of early-age cracking in massive element is the hydration and reactions of the binder that composes the concrete. Indeed, these reactions are highly exothermic and lead to heat generation in the structure. It is thus of primary importance to be able to characterise and predict the heat generation of binders in order to assess the early-age cracking risk of a concrete structure. The first section of this chapter presents the main physical phenomena responsible for this heat generation. It must be kept in mind that only the general phenomena of hydration are presented. The aim is only to present how the chemical reactions lead to heat development and water consumption (which are of interest for our purpose). The reactivity of binder is a large scientific subject, and more detailed review can be found on this subject in other RILEM TCs (for instance, 238-SCM). The second (and main) section of the chapter is dedicated to the modelling of the heat development induced by cement hydration. Several approaches are presented: affinity-based models (that can be easily implemented in finite element codes), microstructural models (even if they are less adapted to the massive structure modelling), data mining, or inverse analysis.

Laurie Lacarrière, Agnieszka Knoppik, Wilson Ricardo Leal da Silva, Tulio Honorio, Vit Šmilauer, Shingo Asamoto, Eduardo M. R. Fairbairn

Chapter 3. Thermal Properties

Abstract

This chapter is dedicated to relevant thermal properties in the scope of massive concrete structures. The initial part of the chapter (Sect. 3.1) pertains to properties that affect internal temperature developments in concrete, namely the thermal conductivity, the heat capacity and the heat exchanges between concrete and the surrounding media. The final part of the chapter (Sect. 3.2) is devoted to the thermal expansion coefficient, which is of fundamental importance to understand and predict the actual volume changes that take place in massive structures due to temperature variations.

Mateusz Wyrzykowski, Agnieszka Knoppik, Wilson R. Leal da Silva, Pietro Lura, Tulio Honorio, Yunus Ballim, Brice Delsaute, Stéphanie Staquet, Miguel Azenha

Chapter 4. Mechanical Properties

Abstract

Prediction of cracking by autogenous, drying shrinkage and thermal strain requires the knowledge of the development of mechanical properties. The main objective of this chapter is to describe the evolution of the mechanical properties, i.e., elastic properties, strengths, shrinkage, and creep, in cement-based materials. Mechanisms and experimental evidences are given thereafter. The influence of mix design, aging, stress level, cracking, etc., is reported. However, evolution of properties regarding interfaces in the case of prestress concrete, for instance, is not discussed (bond behavior). This chapter has strong interactions with the other chapters regarding the modeling (Chap. 2: hydration, Chap. 3: thermal strain, and Chap. 7: shrinkage, creep and cracking).

Farid Benboudjema, Jérôme Carette, Brice Delsaute, Tulio Honorio de Faria, Agnieszka Knoppik, Laurie Lacarrière, Anne Neiry de Mendonça Lopes, Pierre Rossi, Stéphanie Staquet

Chapter 5. Mixture Proportioning for Crack Avoidance

Abstract

In this chapter, the nature, the physical and chemical properties and the content of the concrete constituents will be discussed for the understanding of the way of making an optimized mixture proportioning of the concrete for massive applications where the temperature rise must be minimized.

Stéphanie Staquet, Brice Delsaute, Eduardo M. R. Fairbairn, Roberto Torrent, Agnieszka Knoppik, Neven Ukrainczyk, Eduardus A. B. Koenders

Chapter 6. Temperature Control

Abstract

Temperature rises are definitely one of the most important driving forces for thermal cracking in mass concrete, together with the restraint to deformation. Therefore, amongst the most widespread measures that can be taken to minimize the risks of thermal cracking, the temperature control of concrete since its production and throughout construction is of utmost significance. Following Chap. 5 where temperature control of concrete by limiting the heat generation potential of the binder in the mixture was already addressed, this chapter is dedicated to a review on measures that can be taken to control concrete temperature at several levels, mainly focused in limiting temperature rises due to cement hydration heat: (i) pre-cooling of mix constituents; (ii) cooling concrete during the mixing procedures; (iii) controlling temperature during transport and placement; (iv) selecting and designing suitable surface measures for temperature control; (v) post-cooling with water or air; (vi) scheduling of construction stages.

Miguel Azenha, Ioannis P. Sfikas, Mateusz Wyrzykowski, Selmo Kuperman, Agnieszka Knoppik

Chapter 7. Numerical Modelling

Abstract

This chapter deals with the problem of modelling the behaviour of massive concrete structures. In the last decades, the developments in the field of computational mechanics were significant, so nowadays several numerical techniques are available to this goal, depending on the scale level considered but also on which phenomena/processes are taken into account. In this chapter, we limit the description to approaches/models that can be implemented using the Finite Element Method, which is still the worldwide most used numerical technique. This chapter presents two distinct groups of models. The first group covers deterministic models starting from the simplest ones, which consider simply the thermo-chemo-mechanical behaviour of the material, to more sophisticated approaches which consider also the fluid phases; i.e., they consider concrete as a multiphase porous material. In this first part, a specific section is dedicated to mechanical behaviour modelling considering damage of the material, plasticity, etc. The second group of the models takes into consideration stochastic nature of cracking. These models are formulated specifically for giving a detailed information about cracks spacing and opening in concrete structures in service life conditions.

Francesco Pesavento, Agnieszka Knoppik, Vít Šmilauer, Matthieu Briffaut, Pierre Rossi

Chapter 8. Cracking Risk and Regulations

Abstract

This chapter is focused on the cracking risk at early ages. After general considerations about cracking, the cracking risk prediction is discussed. Two main ways to assess this risk are considered: through an evaluation of the tensile stresses and through an evaluation of the strains. Finally, the evaluation of crack opening at early ages and the reinforcement design in regulations are presented.

Agnieszka Knoppik, Jean-Michel Torrenti, Shingo Asamoto, Eduardus Koenders, Dirk Schlicke, Luis Ebensperger

Chapter 9. On-site Monitoring of Mass Concrete

Abstract

On-site monitoring of mass concrete offers several benefits. It may comprise a wide range of objectives from (i) the maintaining of adequate temperature conditions for the evolution of the desired concrete properties and to (ii) the determination of thermal and mechanical parameters for verification of the calculation models and assumptions applied for crack assessment of the considered structure. Next to very general information on monitoring of mass concrete, this chapter presents different levels of measures with regard to the purpose and expected insights into each level, available instruments and least requirements on practical application, as well as possibilities for result verification. The chapter focuses on both established techniques with comprehensive experiences in many applications and comparably new techniques available on the market. Finally, the presented techniques and approaches were exemplified on three different application examples with regard to different measurement systems as well as types of structures.

Dirk Schlicke, Fragkoulis Kanavaris, Rodrigo Lameiras, Miguel Azenha

Chapter 10. Sustainability Aspects in Mass Concrete

Abstract

This chapter addresses potential alternatives for base raw materials as well as potential solutions for sustainability in mass concrete. Issues like material selection and environment, material properties and mix design, durability, carbon footprint and life cycle analysis (LCA) of mass concretes are reviewed. The focus is put on recycling. Besides the use of conventional SCMs, non-conventional biomass pozzolans, based on combustion of renewable source of energy, like woody ashes, sugarcane bagasse ash and rice husk ash are covered. The synergic use of several mineral SCMs as a partial substituent of Portland cement is addressed. Furthermore, reuse of aggregates from construction–demolition waste as well as natural fiber alternatives to steel and synthetic reinforcements is discussed in detail. Materials selections and the consequence of it on the properties that affect the mix design and material properties specifically related to durability are summarized. An introduction on life cycle assessment (LCA) is given with its pros and cons, followed by its review on different mass concrete mixtures, separately addressing LCA of binders, aggregates, concretes and reinforced concrete structures with placement technologies. Limitations and further research directions are highlighted.

Neven Ukrainczyk, Eduardus A. B. Koenders

Titel: Thermal Cracking of Massive Concrete Structures
herausgegeben von: Dr. Eduardo M.R. Fairbairn
Miguel Azenha
Verlag: Springer International Publishing
Electronic ISBN: 978-3-319-76617-1
Print ISBN: 978-3-319-76616-4
DOI: https://doi.org/10.1007/978-3-319-76617-1