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The Effect of Specimen Size on Acoustic Emission Parameters and Approximate Position of Defects Obtained during Destructive Testing of Cementitious and Alkali-Activated Degraded Fine-Grained Materials
(MDPI, 2023-05-04)Two sizes of test samples were selected to investigate the effect of size on the level of degradation. The smaller test specimens had dimensions of 40 × 40 × 160 mm, and the larger ones had dimensions of 100 × 100 × 400 ... -
Correlating Hydration of Alkali-Activated Slag Modified by Organic Additives to the Evolution of Its Properties
(MDPI, 2023-02-25)This study investigates the relationships between the hydration kinetics of waterglass-activated slag and the development of its physical-mechanical properties, as well as its color change. To modify the calorimetric ... -
Classification of Thermally Degraded Concrete by Acoustic Resonance Method and Image Analysis via Machine Learning
(MDPI, 2023-01-22)The study of the resistance of plain concrete to high temperatures is a current topic across the field of civil engineering diagnostics. It is a type of damage that affects all components in a complex way, and there are ... -
Database 3D Surfaces for Evaluation of Joint Rock Coefficients
(Elsevier, 2016-06-13)Surfaces of rock joints were classified by means of the computerized procedure utilizing three-dimensional reliefs. These standard reliefs were formed as fractal objects using scaling properties of rock joints. Applicability ... -
Effect of carbon nanotubes on the mechanical fracture properties of fly ash geopolymer
(Elsevier, 2016-06-01)Fly ash geopolymer is amorphous aluminosilicate material which is considered as alternative to Portland cement concrete. One of the limiting factors of its utilization is an increased shrinkage and related deterioration ... -
Self-sensing performance of metakaolin geopolymer with carbon nanotubes subjected to repeated compressive loading
(IOP Publishing, 2021-12-21)Alkaline activated binders showing enhanced piezoresistive properties have recently attracted increased interest in research of their application in smart self-sensing components. This study is focused on metakaolin ... -
Decalcification resistance of various alkaliactivated materials
(IOP Publishing, 2021-09-29)The resistance of alkali-activated materials (AAMs) to degradation processes, particularly the decalcification, was studied in this paper. The ground granulated blast furnace slag was alkali-activated using various activators ... -
Advanced Evaluation of the Freeze–Thaw Damage of Concrete Based on the Fracture Tests
(MDPI, 2021-10-25)This paper presents the results of an experimental program aimed at the assessment of the freeze–thaw (F–T) resistance of concrete based on the evaluation of fracture tests accompanied by acoustic emission measurements. ... -
Methods for topography artifacts compensation in scanning thermal microscopy
(Elsevier, 2015-08-01)Thermal conductivity contrast images in scanning thermal microscopy (SThM) are often distorted by artifacts related to local sample topography. Three methods for numerically estimating and compensating for topographic ... -
Computer Evaluation of Asperity Topology of Rock Joints
(Elsevier, 2015-09-07)Grounds beneath large civil engineering structures (bridges, dams, tunnels) that are established in the terrain of rock discontinuities represent a risk of mechanical failure. The surface topology of joint surfaces strongly ... -
Self-Sensing Properties of Fly Ash Geopolymer Doped with Carbon Black under Compression
(MDPI, 2021-08-04)The development of smart materials is a basic prerequisite for the development of new tech-nologies enabling the continuous non-destructive diagnostic analysis of building structures. Within this framework, the piezoresistive ... -
Analysis of Acoustic Emission Signals Recorded during Freeze-Thaw Cycling of Concrete
(MDPI, 2021-03-05)This manuscript deals with a complex analysis of acoustic emission signals that were recorded during freeze-thaw cycles in test specimens produced from air-entrained concrete. An assessment of the resistance of concrete ... -
Effect of Hammer Type on Generated Mechanical Signals in Impact-Echo Testing
(MDPI, 2021-01-28)The impact-echo diagnostic method is a well-known nondestructive pulse compression test method, which can be relatively easily used for the testing of concrete and reinforced concrete elements. The evaluation of the ... -
Heat losses of window compact shutters
(IOP Publishing, 2020-12-09)Window shutters are usually made of wood. They protect glazed windows at their external sides from mechanical damages and inconvenient weather conditions. A typical window compact shutter is described and its thermal ... -
Convective heat transfer inside planar solar collectors
(IOP Publishing, 2020-12-09)There is a permanent interest in improving the construction and thermal properties of the planar solar collectors. Minimizing the heat losses of the collectors and improving their energy gains are some of the relevant ... -
Impedance spectroscopy measurement of metakaolin-based alkali-activated building materials
(IOP Publishing, 2020-12-18)Cement-containing as well as cement-free building materials are regarded as dielectrics. Therefore, electrically conducting admixtures are to be added to them in order to increase their electrical conductivity. Steel or ... -
Acoustic non-destructive testing of high temperature degraded concrete with comparison of acoustic impedance
(MATEC Web of Conferences, 2018-10-30)The paper is focused on non-destructive measurement of high temperature degraded concrete test specimens of three mixtures different by the use of coarse aggregate. Testing is done by ultrasonicpulse velocitymethod and ... -
The experimental comparison of parameters signals of acoustic emission during destructive test on composites based on cement
(MATEC Web of Conferences, 2018-10-29)The paper reports the analysis of acoustic emission signals captured during compressive strength tests of fine-grained cement-based composites of various composition. Acoustic emission monitoring belongs to a non-invasive ... -
The Application of Acoustic Emission Technique to Monitor the Early Setting Process of Cement Pastes
(EDP Sciences, 2019-12-12)The obtained physico-mechanical properties (mainly flexural and compressive strength) of cement-based composite materials depend on various factors (type of mixture, its composition, standard hardening process, proper ... -
Influence of alkali-activated materials placement during curing on their dynamic parameters
(EDP Sciences, 2020-04-16)The production of Portland cement has a considerable environmental impact. Its replacement with alkali-activated binders can contribute to reducing the environmental burden of building production. The paper presents partial ...
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