Search results for "Building"
showing 10 items of 1985 documents
Measurements of pressure and frictional tractions along walls of a large-scale conical shallow hopper and comparison with Eurocode 1991-4:2006
2014
Abstract A silo׳s hopper supports the majority loads induced by the stored particulate solids. Such loads vary from filling to discharging provided the hopper is steep enough to secure a mass flow; when the hopper is too shallow to promote a mass flow, funnel flow usually prevails – where how loads develop along walls of a shallow hopper remains to be addressed. In the paper, normal pressure and frictional traction were measured with pressure transducers as imposed by testing material sand along the walls of a full-scale conical shallow hopper. The transducers were carefully mounted in the designated positions of hopper walls along a generator. To make the measurement results representative…
The Geometry of a Domed Architecture: A Stately Example of Kārbandi at Bagh-e Dolat Abad in Yazd
2016
This paper analyses the kārbandi of the Hashti pavilion at Bagh-e-Dolat Abad in Yazd. Kārbandi is a spatial system obtained through the projection of a star-shaped drawing onto a curved surface. It is characterised by a complex use of geometry and repetitive symmetry. The analysis of its geometrical aspects contributes to an understanding of the traditional rules underlying the original design. The kārbandi of the octagonal vestibule of the Hashti pavilion consists of a complex roof system that completes the octagonal volume of the room below; its intrados presents a pattern of interlocking ribbed arches. The paper also looks at the drawings, module and proportions of the Hashti pavilion, w…
The effectiveness of various types of ventilation on air quality in multi-family buildings
2017
Przepisy prawne oraz normy obligują do kontroli systemów wentylacji budynków jedynie pod względem prędkości strumienia powietrza, co niestety nie zawsze gwarantuje zalecaną ze względów zdrowotnych jakość powietrza. W pracy podjęto badania skuteczności różnych typów wentylacji wielorodzinnych budynków mieszkalnych, ze szczególnym uwzględnieniem wentylacji naturalnej, stanowiącej najczęściej spotykane rozwiązanie w budynkach mieszkalnych w Polsce. Badano wpływ skuteczności wentylacji na podstawowe parametry charakteryzujące jakość powietrza, tj. stężenie ditlenku węgla, wilgotność względną oraz temperaturą. Badano również możliwość regulacji pracy systemu wentylacji budynków wielorodzinnych w…
Badania skuteczności wentylacji pomieszczeń sypialni w wielorodzinnych budynkach mieszkalnych
2017
Skuteczność systemów wentylacji budynków mieszkalnych kontrolowana jest jedynie poprzez pomiar prędkości strumienia powietrza w kanale wentylacyjnym, co nie gwarantuje odpowiedniej kontroli jakości powietrza. W pracy przedstawiono wyniki badań skuteczności wentylacji naturalnej wielorodzinnych budynków mieszkalnych, stanowiącej najczęściej spotykane rozwiązanie w budynkach mieszkalnych w Polsce. Szczególną uwagę zwrócono na wentylację pomieszczenia sypialni, jako pomieszczenia, w którym spędza się około 1/3 czasu w ciągu dnia. Badano wpływ skuteczności systemu wentylacji na podstawowe parametry charakteryzujące jakość powietrza, tj. stężenie ditlenku węgla, wilgotność względną oraz temperat…
Electricity Production from Yeast Wastewater in Membrane-Less Microbial Fuel Cell with Cu-Ag Cathode
2023
Wastewater has high potential as an energy source. Therefore, it is important to recover even the smallest part of this energy, e.g., in microbial fuel cells (MFCs). The obtained electricity production depends on the process rate of the electrodes. In MFC, the microorganisms are the catalyst, and the cathode is usually made of carbon material (e.g., with the addition of Pt). To increase the MFC efficiency (and reduce costs by reducing use of the noble metals), it is necessary to search the new cathode materials. In this work, the electricity production from yeast wastewater in membrane-less microbial fuel cells with Cu-Ag cathode was analyzed. In the first place, the measurements of the sta…
Microstructure and rheological response of laboratory-aged SBS-modified bitumens
2019
Polymer additives are widely used to improve the performance of road bitumens including their resistance to hardening during oxidation, although their oxidative inhibitor effect has not been well documented. This study aims to investigate the effect of laboratory-simulated ageing on the microstructure, and rheological properties of Polymer Modified Bitumens (PMBs) prepared with a Styrene-Butadiene-Styrene (SBS) copolymer and sulphur as a cross-linker. The laboratory ageing was conducted through the Rolling Thin Film Oven (RTFO) and the Pressure Aging Vessel (PAV) procedures. The unaged and aged binders were characterised using the Multiple Stress Creep and Recovery (MSCR) test, Gel Permeati…
Performance-based characterization of recycled polymer modified asphalt mixture
2021
Due to the introduction of secondary materials, the asphalt mixtures to be designed and tested in our laboratories are constantly becoming much more complex than traditional asphalt mixtures making difficult to use conventional laboratory procedure and/or predict expected results. This study proposes a comprehensive characterization of asphalt mixture modified with recycled polymer compound by using both wet and dry process proposing adjustments to laboratory mixing and sample compaction procedure. Accordingly, three AC20 Hot Asphalt Mixture (HMA) were designed and their conventional and performance related properties were assessed by looking at a) Indirect Tensile test (ITS) a) moisture da…
Hydrothermal liquefaction of waste biomass in stirred reactors: One step forward to the integral valorization of municipal sludge
2020
Abstract Hydrothermal liquefaction (HTL) of municipal sludge (MS) was performed at 350 °C for 30 min (subcritical water) and at 400 °C for 0 min (supercritical water) at fixed kinetic severity (LogR0 = 8.9) in static and stirred batch reactors to study the effect of the flow regime on the energy recovery (ER) of the process and on the quality of the products. With adopted experimental procedures it was possible to reduce to less than 10% the yield of lost organic compounds, termed volatiles (VT), and to collect and quantify a liquid hydrocarbon fraction (HC) separated from the biocrude (BC). The highest value of the HC yield, 25% w/w, was obtained in supercritical conditions. The C content …
Tailoring the anionic function and the side chains of comb-like superplasticizers to improve their adsorption
2015
Nowadays admixtures and especially superplasticizers are unavoidable components of the concrete formulation. The high fluidizing efficiency of the comb-like superplasticizers must not overshadow their high costs. This study aims to determine the PCE structure parameters which influence their adsorption in order to enhance their resistance to sulfate competitive adsorption and thus minimize their dosage. The PCE adsorption has been studied on calcite and ettringite which are both surfaces representative of early hydrating cement. The effect of the POE side chain length and density and also of the PCE anionic function i.e. carboxylate, dicarboxylate or phosphate on the adsorption has been ana…
Progress in polymeric material for hydrogen storage application in middle conditions
2014
Hydrogen sorption using a manganese oxide anchored to PEEK (Poly(ether-ether-keton)) matrix was studied. The functionalization process and the obtained results on hydrogen storage capability of the synthesized polymer are reported. The functionalised polymer was characterised by Scanning Electron Microscopy, Transmission Electron Microscopy, X-ray diffraction and Volumetric Hydrogen sorption measurements. Different synthesis conditions in terms of precursor concentration and reaction time were used and the direct correlation between manganese oxide percentage and hydrogen storage capability was confirmed. In this way different powders were synthesised. It is assumed that the sample with 78 …