Carlos Thomas

Carlos Thomas
Universidad de Cantabria | UNICAN · LADICIM - Laboratory of Materials Science and Engineering

Ph.D.

About

98
Publications
21,293
Reads
How we measure 'reads'
A 'read' is counted each time someone views a publication summary (such as the title, abstract, and list of authors), clicks on a figure, or views or downloads the full-text. Learn more
1,748
Citations
Additional affiliations
November 2019 - present
Universidad de Cantabria
Position
  • Professor (Associate)
December 2015 - November 2019
Universidad de Cantabria
Position
  • Professor (Assistant)
January 2006 - December 2012
Universidad de Cantabria
Position
  • Researcher

Publications

Publications (98)
Article
Concrete with siderurgical aggregates (SA) is a sustainable construction material with great potential as structural concrete. For this reason, studies must be carried out on the behavior of concrete against prestressed elements, studies that open the door to new applications such as buildings, bridges or foundations. In this study, the feasibility...
Article
This work describes the impact behaviour of a hybrid fibre-particulate composite composed of glass-carbon fibres and easily dispersible microparticles. The effects of fibre stacking sequence (carbon-C5, glass-G5, C2G3, G3C2, GCGCG and CG3C), particle type (silica, cement and carbon microfibers-CMF) and matrix-fibre volume fraction (40/60 and 60/40)...
Article
Full-text available
Modern society demands more sustainable and economical construction elements. One of the available options for manufacturing this type of element is the valorisation of end-of-life waste, such as, for example, the recycling of polymers used in industry. The valorisation of these wastes reduces costs and avoids the pollution generated by their landf...
Article
The world is changing, and consequently so are policies on the use of natural resources. One of the most convenient ways to reduce the consumption of natural aggregates in the production of more sustainable construction materials is the use of recovered industrial by-products. In this study, concretes are designed using siderurgical aggregates from...
Article
Full factorial designs are conducted to identify the effects of the incorporation of microparticles of silica, Portland cement and carbon laminate wastes (carbon microfibres - CMF), at 3, 6 and 9 wt% levels, on the mechanical performance of epoxy polymers and single carbon fibre joints at two grammage levels (200 and 600 g/m2). Particulate reinforc...
Article
The current trend in the development of self-compacting concrete with sustainable construction materials has served as a guide to design a novel self-compacting concrete, with siderurgical by-products (steel slag aggregates and cupola slag powder as supplementary cementing material) that also meets the demands of high-performance concrete. This res...
Chapter
With the advancement of technology and the use of radioactive materials in medical systems for more accurate diagnosis of diseases, the need to maintain the health of medical staff and people who are constantly exposed to these rays has become a matter of urgency. To prevent the spread of these rays, either thick concrete walls should be used or co...
Chapter
The currently increasing consumption of resources and the environmental cost associated with concrete manufacture indicate the requirement of designing environmentally friendly concretes, to continue being a reference point in construction. One of the most common ways to reduce its environmental cost is the incorporation of wastes like construction...
Chapter
Owing to major environmental problems associated with cement production, scientists are trying to replace cement with other environmental friendly materials. Rice husk ash as a by-product in the agricultural industry with chemical and behavioral components similar to cement is a suitable substitute material. Researches have shown that this material...
Chapter
In this chapter, the foundry sand produced by the steel-making process of ferrous and nonferrous materials and the concrete produce with them is described. The physical and chemical properties of the foundry sand depend on the type of casting process, the type and amount of additives used for molding, the number of times that the sand was recycled,...
Article
This research analyses the strain behaviour of fibre-reinforced concrete (FRC) in the event of a creep episode. The analysis of creep experienced by FRC specimens during the test reflects better performance than that predicted by the EHE-08 standard. The authors propose a formulation for the evaluation of creep strain undergone by FRC. During the r...
Article
Full-text available
High performance colloid flake of carbon is gaining interest due importance in meeting the challenges of the globe. To make novel superior materials, the pulverized fuel ash-green adhesive based construction materials modified with the flake of carbon and the colloid flake of carbon were evaluated in view of synthesis, physico-mechanical properties...
Article
Due to the large amount of CO2 emissions produced nowadays by the construction sector, the scientific community is looking for measures that will bring constructions to the be as environmental-friendly as possible. One of the most popular lines of research is the use of construction waste as recycled aggregates for the production of recycled aggreg...
Preprint
Full-text available
Synthesis, physico-mechanical properties, material processing, and math models of novel superior materials doped flake of carbon and colloid flake of carbon, Journal of Materials Research and Technology, https:// Abstract High performance colloid flake of carbon is gaining interest due importance in meeting the challenges of the globe. To make nove...
Article
Full-text available
The aim of this study is to evaluate the usability of new cement (NC) made by the burning of quinary by-product to make commercial binders. Chemical analysis of the by-products and NC as well as X-ray diffraction (XRD) analysis of NC, fineness, density, consistency, and setting time of NC paste, and slump in addition to compressive strength (CS)...
Preprint
Full-text available
The aim of this study is to evaluate the usability of new cement (NC) made by the burning of quinary by-product to make commercial binders. Chemical analysis of the by-products and NC as well as X-ray diffraction (XRD) analysis of NC, fineness, density, consistency, and setting time of NC paste, and slump in addition to compressive strength (CS) an...
Article
Full-text available
One of the biggest challenges in facilitating the installation of concrete is the development of fibre-reinforced concrete. Although nowadays fibre reinforced concrete is relatively common, it is still necessary to deepen in the study on its behaviour, especially regarding its fatigue behaviour. This paper proposes a new methodology to analyse the...
Article
The most recommendable frequency range for concrete fatigue tests is between 1 and 15 Hz. It has been clearly established that performing the tests at low frequency (<1 Hz) reduces the fatigue limit because it increases test time and therefore, creep damage. On the other hand, there are not enough studies analysing tests above 15 Hz, which could gr...
Article
Mineral admixtures are used in ordinary and self-compacting mortar to reduce carbon dioxide emission and enhance the performance of mortar at the fresh and hardened states. This paper reports the effect of the content and the fineness of natural pozzolana (NP) on rheological, compressive strength, total and autogenous shrinkage properties of self-c...
Article
Full-text available
The high consumption of natural resources in the industrial sector makes it necessary to implement measures that enable the reuse of the waste generated, seeking to achieve circular economy. This work assesses the viability of an alternative to the use of CEM III B 32.5 R cement in mortars for the internal coating of centrifugally spun cast iron pi...
Article
Full-text available
The huge increase in production of construction and demolition waste (CDW) worldwide is leading to the valorisation of as recycled aggregates. One of the most promising alternatives is its use as a recycled aggregate in the manufacture of structural concrete, which motivates the study of the dynamic behaviour of these materials in order to ensure t...
Article
Full-text available
Concrete produced from electric arc furnace steel slag aggregates is one of the items that is highly regarded due to its strength, environmental friendliness and cost-effectiveness. Despite the growing interest in using this type of concrete, there are still doubts about the mix proportions and addition effects of electric arc furnace steel slags....
Article
Full-text available
Obtaining new materials capable of meeting society’s demands motivates the search for new solutions that are capable of satisfying twofold requirements: respect for the environment and obtaining more durable and resistant materials. Cupola slag is a by-product generated in the process of obtaining ductile iron. When the slag undergoes rapid cooling...
Article
The design of concrete often requires numerous mix proportions and tentative mixings, which translates into a great number of specimens and tests. The process may be optimized by using small-scale specimens, which results in the saving of material, equipment and time, offering advantages such as better handling, easy kneading or smaller curing spac...
Article
The steel industry generated approximately 18 Mt of electric arc furnace slags in 2016. It is estimated that construction generates 10% of man-made CO2 emissions. To mitigate these two problems, the valorisation of these slags by using them to manufacture siderurgical concrete is considered. As there is a large volume of these aggregates, which hav...
Article
Full-text available
The benefits of recycling in the construction sector have been widely demonstrated and are unquestionable [...]
Article
Full-text available
Cement-treated bases are soils, gravels or manufactured aggregates mixed with certain quantities of cement and water in order to improve the characteristics of a base or sub-base layer. Due to the exploitation of natural aggregates, it is a matter of importance to avoid shortage of natural resources, which is why the use of recycled aggregates is a...
Chapter
Precast companies produce high amounts of waste due to the excess of fresh concrete not used during the manufacturing of the pieces or the rejection of elements with aesthetic or geometric defects. In recent years, because of the increased environmental awareness and to get a greater sustainability in the precast factories, this waste has not been...
Chapter
Currently a large number of countries have regulated the application of recycled aggregates, steel slag, incineration ashes among others for the manufacture of cement-based materials, as well as the characteristics that recycled aggregate concrete must present. Also, in the past two decades, a labor-intense investigation in this line has been carri...
Chapter
Because using recycled aggregates (RAs) in concrete production becomes a standard practice, a new problem arises: how do the RAs produced from concrete made itself with RAs behave? Moreover, how does the recurrence of this produce-recycle in concrete affect the performance of the newer aggregates and of the concrete mixes made with them? In the fol...
Chapter
Full-text available
This chapter discusses the feasibility of using steel slags for the manufacture of radiological concrete. For this purpose, the most penetrating types of nuclear radioactivity (gamma and neutrons) are considered to analyze the variables that affect their attenuation, the ways to measure their attenuation, and the desirable conditions for effective...
Chapter
Nowadays, it is necessary to reduce the amount of aggregates extracted from quarries and the valorization of construction and demolition wastes as aggregates for the manufacture of recycled concrete can contribute to that end. One of the possible applications of this recycled concrete is the manufacture of elements for railway superstructure, such...
Article
Full-text available
This work investigates epoxy composites reinforced by randomly oriented, short glass fibres and silica microparticles. A full-factorial experiment evaluates the effects of glass fibre mass fraction (15 and 20 wt%) and length (5 and 10 mm), and the mass fraction of silica microparticles (5 and 10 wt%) on the apparent density and porosity, as well as...
Article
Concrete structures are increasingly affected by fatigue damage, while new slender building structures with greater mechanical requirements make it necessary to deepen knowledge of their behaviour under fatigue loading. In this research, high-strength plain concrete was studied under two different frequencies of cyclic compressive stress. Wöhler cu...
Article
Full-text available
The research presented in this article analysed the influence of incorporating precast concrete waste as an alternative to coarse aggregate in self-compacting concrete to generate new precast elements. The experimental study involved the characterization of recycled aggregate and the design of the mix of the new self-compacting concrete (SCC). The...
Article
The objective of this paper was to analyze the influence of crushed precast concrete waste on the transport mechanisms as indicators of the durability of precast recycled self-compacting concrete (SCC) as an alternative to the coarse fraction of natural aggregate. The replacement percentages were 20%, 50% and 100%, by weight, of the silica gravel 2...
Article
Full-text available
Increasing amounts of sustainable concretes are being used as society becomes more aware of the environment. This paper attempts to evaluate the properties of precast concrete elements formed with recycled coarse aggregate and low clinker content cement using recycled additions. To this end, six different mix proportions were characterized: a refer...
Article
Designing or analysing the influence of fatigue on concrete structures is becoming increasingly important for a number of structural elements. For this reason, it is necessary to define a method capable of determining the concrete's fatigue limit in the most economical, fast and efficient way. The aim of this study is to compare and correlate diffe...
Article
Full-text available
Self-compacting concrete modifies its workability with small variations in the amount of superplasticizer additive. For this reason, large number of tests are required to monitor its workability. In order to determine the appropriate amount of additive for a single mix, the evolution of the power consumption of the concrete mixer during the additio...
Article
Full-text available
The development of self-compacting concretes with electric arc furnace slags is a novelty in the field of materials and the production of high-performance concretes with these characteristics is a further achievement. To obtain these high-strength, low-permeability concretes, steel slag aggregates and cupola slag powder are used. To prove the effec...
Chapter
In this chapter, the advancements in shielding materials used in the design of spent fuel containers are presented. Factors such as the target lifetime, the exposure environment, the type of container, and the energy spectrum of the source term are analyzed. The main types of containers and commercial products that incorporate different materials a...
Chapter
In this chapter, the filler or powder materials used in the radiation shielding industry are presented. The current trend is the use of boron-based compounds, abundant materials with relatively accessible costs and with which developers have extensive experience. Today more efficient boron-based compounds are still being developed, although the use...
Article
Full-text available
The search for more sustainable construction materials, capable of complying with quality standards and current innovation policies, aimed at saving natural resources and reducing global pollution, is one of the greatest present societal challenges. In this study, an innovative recycled aggregate concrete (RAC) is designed and produced based on the...
Article
Full-text available
Concrete fatigue behaviour has not been extensively studied, in part because of the difficulty and cost. Some concrete elements subjected to this type of load include the railway superstructure of sleepers or slab track, bridges for both road and rail traffic and the foundations of wind turbine towers or offshore structures. In order to address fat...
Article
In a future scenario in which all the concrete is recycled concrete, it will be necessary to recycle the recycled concrete. However, it is known that the recycling of concrete implies a loss of properties. This paper shows an innovative technique, the computerized microtomograph, used to evaluate closed porosity, volume of limestone aggregate fract...
Article
The recycling of the fine fractions from construction and demolition wastes is an environmental and technological challenge. In view of its incorporation as recycled aggregate in the manufacture of concretes, this work analyzes its influence on the mechanical response of these concretes to the action of variable loading, which can lead to failures...
Article
Cementitious composites reinforced with silica, silicon carbide or carbon microfibres are designed, manufactured, characterised and tested as porous restrictor for aerostatic bearings. Carbon microfibres are residues obtained from the cutting process of carbon fibre-reinforced polymers. Porosity, permeability, flexural strength and stiffness are qu...
Article
Traditionally, concrete has been used in radiotherapy rooms, in nuclear fuel containers, in nuclear power plant foundations and other structures using large thicknesses to shield the radiation. Currently, the development of concrete technology allows us to produce cement-based composite materials incorporating fibers, improving mechanical propertie...
Article
In this study, the results of the physical and mechanical characterization of a high-density structural concrete for radiation shielding subjected to different intensities of thermal shock are analyzed. The concrete has been designed using high-density natural aggregates and steel reinforcing fibers, according to structural concrete requirements. T...
Article
Slab track is replacing obsolete ballasted track. This work proposes crushing out-of-service ballast and sleepers for use as aggregates for constructing the slab track. Three kinds of recycled self-compacting concretes were designed; the first one with aggregates from crushed ballast, the second one with aggregates from crushed sleepers and the thi...
Article
This work investigates the incorporation of disposed carbon microfibres (CMF) obtained from the cutting process of laminate composites into epoxy polymers at different mass fractions (0, 2.5, 5, 7.5 and 10wt%). The elastic modulus and strength under tensile, compressive, flexural loads and impact resistance are investigated via Analysis of Variance...
Article
Full-text available
Rigid particles have been incorporated into laminated composites, especially to enhance their bending performance attributed to the stiffening of the matrix phase (i) and the increased interlaminar shear resistance (ii). In order to better evaluate the improvement mechanism provided by the particulate inclusions, this work investigates the incorpor...
Article
Full-text available
Society is becoming aware of the environment and progressively using more recycled aggregates to produce recycled structural aggregate concrete. In addition, many researches have analysed the properties of hardened recycled aggregate concrete, but few of them have focused on the mixing method and the consequences that it has on the properties of co...
Article
Full-text available
This paper presents the results of a study of permeability and its influence on the durability of recycled concrete exposed to an aggressive environment. Recycled concretes with 20%, 50% and 100% in weight of recycled aggregate and 24 effective w/c ratios have been exposed directly to a marine environment. Control specimens cured in a humidity cham...
Article
Waste from scrap tires is one of the most environmentally harmful waste since it leads to significant soil and air pollution. This work investigates the effect of recycled rubber particles incorporation into cementitious composites modified with epoxy polymer. A Design of Experiment (DoE) was conducted to identify the effect of epoxy polymer inclus...
Article
This paper presents a novel technique used to analyse the volume of adhered mortar to the recycled aggregate. A computerized microtomograph (μCT) device was used to evaluate the volume of the aggregate, the volume of natural aggregate and the volume of adhered mortar. To this end, a natural aggregate has been characterized, using the μCT, with whic...