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A healthy built environment is an issue of crucial importance, especially in the context of the dramatic Covid-19 outbreak. Also, according to The Serum Institute, the world largest vaccine manufacturer, there will not be enough doses to inoculate the entire world until 2024. That fact is independent discovery of the alarming consequences of the post-Covid syndrome (“long Covid”). As it is briefly discussed in this chapter, the necessary interactions between the many researchers of the different areas of the world whose work has connections to the built environment-namely, civil engineers, architects, microbiologists, and epidemiologists-are rare, thus hampering the efforts needed to tackle the pandemics. The objective of this multiauthored text to is provide the necessary background to learn about virus, bacteria, and fungi in the built environment and methods to eradicate or reduce their numbers., (undefined)

This chapter starts by addressing the impact of Covid-19 on the time spent by the general population indoors and how this reality exacerbates problems associated with pollutant concentration in indoor air. An introduction on a few indoor pollutants and also on toxic materials used in the built environment is given. Some prospective considerations about the importance of a healthy built environment are included. An outline of the book is also given., (undefined)

This paper reports experimental results on the thermal performance of fly ash-based geopolymeric mortars containing different percentages of phase change materials (PCMs). These materials have a twofold eco-efficient positive impact. On one hand, the geopolymeric mortar is based on industrial waste material. And on the other hand, the mortars with PCM have the capacity to enhance the thermal performance of the buildings. Several geopolymeric mortars with different PCM percentages (10%, 20%, 30%) were studied for thermal conductivity and thermal energy storage, info:eu-repo/semantics/publishedVersion

GEP has been employed in this work to model the compressive strength of different types of geopolymers through six different schemes. The differences between the models were in their linking functions, number of genes, chromosomes and head sizes. The curing time, Ca(OH)2 content, the amount of superplasticizer, NaOH concentration, mold type, aluminosilicate source and H2O/Na2O molar ratio were the seven input parameters considered in the construction of the models to evaluate the compressive strength of geopolymers. A total number of 399 input-target pairs were collected from the literature, randomly divided into 299 and 100 sets and were trained and tested, respectively. The best performance model had 6 genes, 14 head size, 40 chromosomes and multiplication as linking function. This was shown by the absolute fraction of variance, the absolute percentage error and the root mean square error. These were of 0.9556, 2.4601 and 3.4716 for training phase, respectively and 0.9483, 2.8456 and 3.7959 for testing phase, respectively. However, another model with 7 genes, 12 head size, 30 chromosomes and addition as linking function showed suitable results with the absolute fraction of variance, the absolute percentage error and the root mean square of 0.9547, 2.5665 and 3.4360 for training phase, respectively and 0.9466, 2.8020 and 3.8047 for testing phase, respectively. These models showed that gene expression programming has a strong potential for predicting the compressive strength of different types of geopolymers in the considered range.

In the present study, six different models based on artificial neural networks have been developed to predict the compressive strength of different types of geopolymers. The differences between the models were in the number of neurons in hidden layers and in the method of finalizing the models. Seven independent input parameters that cover the curing time, Ca(OH)2 content, the amount of superplasticizer, NaOH concentration, mold type, geopolymer type and H2O/Na2O molar ratio were considered. For each set of these input variables, the compressive strength of geopolymers was obtained. A total number of 399 input-target pairs were collected from the literature, randomly divided into 279, 60 and 60 data and were trained, validated and tested, respectively. The best performance model was obtained through a network with two hidden layers and absolute fraction of variance of 0.9916, the absolute percentage error of 2.2102 and the root mean square error of 1.4867 in training phase. Additionally, the entire trained, validated and tested network showed a strong potential for predicting the compressive strength of geopolymers with a reasonable performance in the considered range.

Several authors reported a severe reduction in undergraduate applications to civil engineering in different countries. This fact will lead to a severe shortage of civil engineers in the coming years. These professionals will be especially needed to tackle infrastructure construction and rehabilitation on a context of climate change and increased world population. Part of the explanation for the low attraction capability of civil engineering relates to the fact that this course is viewed as low tech. A scientific and technical upgrade of the civil engineering curriculum is, therefore, needed. Nano and biotech based materials and technologies for the built environment could refresh the attraction of this area. The environmental challenges faced by a Planet that has about 220,000 new inhabitants each day and that will have more than 9,7 billion people by 2050 and 11,2 billion by 2100 means that a strong eco-efficiency focus of the new curriculum is also needed. On this context a proposal on a new curriculum on Smart Eco-Efficient Built Environment is suggested that could provide the construction market with professionals with a set of new and enhanced holistic high tech skills., (undefined)

Carbonation is a major cause of concrete structures deterioration leading to expensive maintenance and conservation operations. The eco-efficient construction agenda favours the increase of the use of supplementary cementing materials (SCMs) to reduce Portland cement’s consumption and also the use of recycled aggregates concrete (RAC) in order to reduce the consumption of primary aggregates and to avoid landfill disposal of concrete waste. There is a wide range of literature published on the field of concrete carbonation related to the use of SCMs and/or RCA. However, the different conditions used by different authors limit comparison and in some cases contradictory findings are noticed. Besides, since most investigations are based on the use of the phenolphthalein indicator, which provides a poor estimate of the real concrete carbonation depth, there is a high probability that past researches could have underestimate the corrosion potential associated to concrete carbonation. This paper reviews current knowledge on concrete carbonation addressing carbonation depth’s measurement, the use of SCMs and or RAC.

This chapter starts with an overview of the unsustainable energy consumption which is due to fast population growth and related greenhouse gas emissions. The case of energy efficiency building is introduced. A short analysis of the ambitious European nearly zero-energy building (NZEB) target is presented. Shortcomings of current materials concerning energy building efficiency are reviewed. Examples of promising nano- and biotech-based materials for energy building efficiency are briefly covered. A book outline is presented., (undefined)

This paper presents an experimental study to evaluate the influence of physical and geometrical properties of granite and limestone aggregates on the durability of a C20/25 strength class concrete. Different granite and limestone aggregates were collected from seven quarries. Physical, geometrical and mechanical properties of aggregates as well as the rock weathering state were quantify by several tests such as, abrasion, surface hardness, uniaxial compressive strength, ultrasonic pulse velocity, water absorption by capillarity, vacuum water absorption and oxygen permeability. Using aggregates from each quarry, several C20/25 strength class concrete mixes have been produced, with the same workability and volume proportions. Concrete specimens have been cured under water for 90 days; after that time concrete durability parameters were obtained through tests such as, vacuum water absorption, capillarity water absorption, water permeability and oxygen permeability. Relevant statistical correlations have been obtained between absorption and permeability test of rock material and rock deterioration state (weathering). Valid statistic correlation was also obtained between durability parameters as well as among aggregates geometrical properties and concrete durability parameters.

Part 1 Eco-efficiency of Portland cement concrete: Environmental impact of Portland cement production Low binder intensity eco-efficient concretes Life cycle assessment (LCA) aspects of concrete. Part 2 Concrete with supplementary cementitious materials (SCMs): Natural pozzolans in eco-efficient concrete Artificial pozzolans in eco-efficient concrete Tests to evaluate pozzolanic activity in eco-efficient concrete Properties of concrete with high volume pozzolans Influence of supplementary cementitious materials (SCMs) on concrete durability Performance of self- compacting concrete (SCC) with high volume SCMs High volume ground granulated blast furnace slag (GGBFS) concrete Recycled glass concrete. Part 3 Concrete with non-reactive wastes: Municipal solid waste incinerator (MSWI) concrete Concrete with polymeric wastes Concrete with construction and demolition wastes (CDW) An eco-efficient approach to concrete carbonation Concrete with polymers. Part 4 Future alternative binders and use of nano and biotech: Alkali-activated based concrete Sulfoaluminate cement Reactive magnesia cement Nanotechnology for eco-efficient concrete Biotechconcrete: An innovative approach for concrete with enhanced durability.

The volume of polymeric wastes such as tyre rubber and polyethylene terephthalate (PET) bottles is increasing at a fast rate. An estimated 1000 million tyres reach the end of their useful lives every year and 5000 million more are expected to be discarded in a regular basis by the year 2030. Only a small part is currently recycled and millions of tyres are just stockpiled, landfilled or buried. As for PET bottles annual consumption is over 300 000 million units. The majority is just landfilled. This chapter reviews research published on the performance of concrete containing tyre rubber and PET wastes. Furthermore it discusses the effect of waste treatments, the size of waste particles and the waste replacement volume on the fresh and hardened properties of concrete.

Concrete infrastructure is crucial to services and economic activities of modern civilzation. Unfortunately concrete deteriorates due to several causes including mechanical deterioration, like impact or excessive loading or deterioration due to physical causes like erosion or shrinkage. More frequently, however, it deteriorates by chemical detrimental reactions when it is exposed to environmental conditions containing chlorides from seawater or from de-icing salts and other aggressive media. Climate change is also being increasingly responsible for premature deterioration of concrete infrastructure. As a consequence, worldwide concrete infrastructure repair rehabilitation needs are enormous and the costs are staggering. This book provides an updated state-of-the-art review on eco-efficient repair and rehabilitation of concrrete infrastructure. Presented over three parts : the first part reviews service life estimation, monitoring of concrete structures, durability performance, and field assessment. Part II focuses on innovative materials for repair and rehabilitation including geopolymers, ECC and materials with self-sensing properties. Part III addresses eco-efficient and cost-effective design, accountability of climate change impacts, and includes case studies using life cycle analysis and life cycle cost analysis. This book is an essential reference resource for material scientists, civil and structural engineers, architects, contractors, designers, and other professionals working in construction on the repair and rehabilitation of concrete infrastructures.

The topic of this chapter is the confrontation between two different construction technologies through life cycle assessment methods: wood and concrete. Nowadays, cradle-to-gate and cradle to cradle LCA analyses are used successfully in sustainable building design and construction. Our research is focused on the specific European context, trying to enhance the usefulness of the methods from a design perspective, if system boundaries are carefully defined and data sets accurately selected and adapted. According to LCA analysis, wood structures demonstrate an overall better environmental performance, but distinctions and contradictory results emerge in different categories of impact.

Many aspects of concrete have been researched and published over the last few years. Many books have covered the properties, applications and more recently about the durability of concrete. Eco-efficient concrete will look at many different types of concrete and the environmental performance of each type whilst using the latest research on this subject. The first part of the book analyses concretes based on new chemistry cements (sulfoaluminate and magnesia cements) associated to low CO2 emissions. The second part the moves on to analysing concretes that have been partially replaced with Portland cement and discusses pozzolanic activity or hydraulic properties. This chapter describes the use of different polymers, added in fresh or hardened hydraulic cement or to replace the cement. The introduction of polymers, in or with concrete, is able to modify its characteristics and properties, to protect or to repair concrete elements.

This chapter presents the main wood preservatives with respect to their potential hazard due to biocide release from treated wood products. The chapter first discusses the toxicological properties of the active substances and the chemistry of the treated wood products in the exposure conditions. Then, after presenting the main physico-chemical mechanisms at the origin of biocide release, a section is dedicated to methodologies applicable to toxicity assessment in service life scenarios. The main ecotoxic effects and examples of studies at laboratory or field scale are given, followed by several trends and alternative solutions.