Search results for "construction material"
showing 10 items of 31 documents
Novel biomass fly ash-based geopolymeric mortars using lime slaker grits as aggregate for applications in construction: Influence of granulometry and…
2019
Abstract This work discusses the influence of the aggregate granulometry and the binder/aggregate ratio on the engineering properties of novel green geopolymeric mortars. Two wastes generated by a Portuguese Kraft pulp industry are employed to manufacture the material: lime slaker grits (used as aggregate) and biomass fly ash (to partially replace the metakaolin − 70 wt% substitution). The novel geopolymeric mortars could find innovative applications as sustainable construction materials. The studied mix design foresees the use of several grits granulometric ranges and ratios binder/aggregate to discuss workability, water sorptivity, and mechanical performance of the novel mortars. To date,…
Unexplored alternative use of calcareous sludge from the paper-pulp industry in green geopolymer construction materials
2020
Abstract Calcareous sludge is an alkaline waste produced by the paper pulp industry that is commonly disposed of in land-fill. However, recent studies and the European regulations discourage such practice. This work investigates an alternative and innovative way to recycle and reuse this waste, as filler, in the production of green geopolymeric mortars intended for applications in construction. This is the first time that this calcareous sludge is used to produce novel waste-based materials, in both construction and geopolymer technology. The novel alkali-activated mortar also uses biomass fly ash – another slightly investigated waste stream – to substitute the metakaolin (70 wt% substituti…
A sustainable replacement for TiO2 in photocatalyst construction materials: Hydroxyapatite-based photocatalytic additives, made from the valorisation…
2018
The use of waste materials and by-products in building materials is of increasing importance to improve sustainability in construction, as is the incorporation of photocatalytic materials to both combat atmospheric pollution and protect the structures and façades. This work reports the innovative use of photocatalytic hydroxyapatite (HAp) based powders, derived from Atlantic codfish bone wastes, as an additive to natural hydraulic lime mortars. HAp is the main component of bone, and hence is non-toxic and biocompatible. This is the first time that such a calcium phosphate-based photocatalyst, or indeed any fish/marine derived wastes, have been added to building materials. A key factor is th…
Gamma activity and geochemical features of building materials: estimation of gamma dose rate and indoor radon levels in Sicily.
2001
A high-purity germanium detector has been used to measure the abundance of radium (Ra), thorium (Th) and potassium (K) in building materials used in Sicilian dwellings. The measurements were performed to evaluate which material was suitable for the construction of an enclosure, which would have a low background emission. The materials examined in this work showed concentrations of 226Ra, 232Th and 40K dramatically variable depending on the lithologies, particularly in the case of blocks, sands and aggregates commonly used in building materials in Sicily. The results are discussed and a criterion is indicated to reduce the radiation dose to humans. Since radon inlet is a major health problem…
Timber framed with masonry infill: a historical anti-seismic device. The Portuguese Pombaline gaiola.
2017
La ricostruzione postsismica e la prevenzione sismica sono stati da sempre un fondamento costruttivo.Questo studio analizza la tipologia costruttiva della gaiola pombalina, un sitema costruttivo e strutturale molto diffuso in Portogallo ma non solo, adottato a Lisbona a seguito del terremoto del 1755. Si analizzano i materiali e le tecniche costruttive, gli elementi utili al rinforzo e consolidamento della struttura muraria, ampiamente diffuso in area mediterranea a partire dal XVIII secolo.Questo sistema costruttivo può e deve anche oggi essere considerato un utile presidio antisismico da riconoscere e preservare da interventi incolti, se non addirittura da incongrue demolizioni. Post-seis…
Dried-fruit shell reuse in green construction and building materials
2023
Bio-architecture is a new way of designing and building in line with the European Green Deal and in light of the circular economy principles. This new green approach is guiding the entire construction life cycle toward eco-sustainability and environmental friendliness, from the beginning to the end of the building process. In addition to the use of environmentally-friendly and high-performance building and construction materials, it is necessary to use new technologies that can reduce the environmental footprint. This paper aims to examine the possible reuse of biological wastes of agricultural origin of the Mediterranean basin, whose massive production generates a number of problems for th…
Numerical vibroacoustic analysis of plates with constrained-layer damping patches
2011
International audience; A numerical vibroacoustic model that can manage multilayered plates locally covered with damping patches is presented. All the layers can have an on-axis orthotropic viscoelastic behavior. Continuity of displacements and transverse shear stresses at each interface is enforced, which permits to write the entire displacement field in function of the displacements of the-common-first layer, leading to a two-dimensional plate model. The problem is then discretized by Rayleigh-Ritz's method using a trigonometric basis that includes both sine and cosine functions in order to treat various boundary conditions. The excitation can be of mechanical kind (concentrated or distri…
Coffee biowaste valorization within circular economy: an evaluation method of spent coffee grounds potentials for mortar production
2021
Abstract Purpose Spent coffee grounds (SCG) are biowastes extensively generated within the coffee supply chain. Nowadays, their disposal represents an increasing environmental concern due to its toxicity and organic nature. With the estimated increase of coffee production and consumption in the upcoming years, there is an imperative need to find a proper reverse option, along with a novel industrial application, which allows for the valorization of this coffee by-product within a circular economy perspective. This study aims at investigating a potential reuse of spent coffee grounds to produce novel construction materials to be used for sustainable buildings. Methods After having illustrate…
Tracing anthropogenic thallium in soil using stable isotope compositions.
2014
Thallium stable isotope data are used in this study, for the first time, to apportion Tl contamination in soils. In the late 1970s, a cement plant near Lengerich, Germany, emitted cement kiln dust (CKD) with high Tl contents, due to cocombustion of Tl-enriched pyrite roasting waste. Locally contaminated soil profiles were obtained down to 1 m depth and the samples are in accord with a binary mixing relationship in a diagram of Tl isotope compositions (expressed as e(205)Tl, the deviation of the (205)Tl/(203)Tl ratio of a sample from the NIST SRM 997 Tl isotope standard in parts per 10(4)) versus 1/[Tl]. The inferred mixing endmembers are the geogenic background, as defined by isotopically l…
Compatible rehabilitation of the Sicilian rural architecture: the case study of "Calcibaida" in Caltavuturo
2020
The Sicilian common typological form of rural estate is the masseria, typical of the latifundium. More particularly, it is a large fortified farm built to control and manage a vast land-property, the old fiefdoms. This paper will analyse the masseria Calcibaida as an eminent example of the mentioned Sicilian rural world. Calcibaida is located in the territory of Caltavuturo, in the centre of Sicily, within the mountain landscape of the Madonie mountains. The complex consists of a compact aggregate of buildings with an internal courtyard and a close large warehouse, further embellished by a fine drinking trough. The typological characteristics, materials and construction technologies of the …