Global ETD Search
Search theses and dissertations gathered from participating repositories worldwide. Every result links back to the library that holds it. No account is needed.
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Showing 1 to 20 of 24 for “"Ultrasonic Pulse Velocity"”.
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Laboratory Ultrasonic Pulse Velocity Logging for Determination of Elastic Properties from Rock Core
… property analysis surveys that combine acoustic velocity and density data to calculate acoustic estimates of elastic moduli. However, logistical concerns arise since the approach must be conducted at the advancing tunnel face. As a result, borehole mechanical property analyses are rarely used. …
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Investigation of the Addition of Basalt Fibres into Cement
… evaluating the properties of concrete such as ultrasonic pulse velocity and impact echo tests. One of major issues with concrete (which has cement as its prime ingredient) is that unlike steel it is quasi-brittle material. It tends to want to crack when tensile stresses develop. Fibres have …
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Ensayos de información y extracción de probetas testigo en hormigones autocompactantes
… core strength determinations, rebound hammer and ultrasonic pulse velocity applied to Traditionally Vibrated Concrete have been thoroughly spread and widely accepted. However, there are insufficient studies on its adaptability in new kinds of concrete, especially in Self-Consolidating Concrete. In …
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Characterizations of concretes with alkali-activated binder and correlating their properties from micro- to specimen level
… these findings. The results also show that the ultrasonic pulse velocity technique can be effectively used to estimate dynamic modulus of elasticity, compressive strength, and stress level of concrete with AAB for wide range of mixes, curing temperature, and ages. Finally, based on a detailed …
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NDT to characterize 3D printed concrete interlayer bonds
… applied four NDT methods (x-ray radiography, ultrasonic pulse velocity (UPV), vibration resonance, and multi-element array ultrasonics) to idealized, layered concrete specimens that simulate layers of a 3D printed structure. The bond interfaces in the samples were characterized into well …
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The elastic properties of calcium leached cement pastes and mortars : a multi-scale investigation
… measured using three different techniques: (a) Ultrasonic Pulse Velocity, (b) Resonant Frequency, and (c) Uniaxial Compression. The microscopic effect (10-5 - 10-7 m) is quantified using state-of- the-art Nanoindentation tests. Scanning Electron Microscope images complete the characterization by …
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Acoustic and non-acoustic performance of coal bottom ash as sound absorptive material for reducing railway noise level
… water absorption, water permeability and ultrasonic pulse velocity. The increase in CBA percentage in the concrete mixture has affected the compressive strength and splitting tensile strength of the sample which were lower than that of control concrete. CBA concrete can be recommended as …
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Air-coupled ultrasonic tomographic imaging of concrete elements
Ultrasonic tomography is a powerful tool for identifying defects within an object or structure. This method can be applied on structures where x-ray tomography is impractical due to size, low contrast, or safety concerns. By taking many ultrasonic pulse velocity (UPV) readings through the object, …
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Microporoelastic modeling of organic-rich shales
… shales. The models are calibrated by means of ultrasonic pulse velocity measurements of elastic properties and validated by means of lab measured nanoindentation data. Sensitivity analyses using Spearman's Partial Rank Correlation Coefficient show the importance of porosity and Total Organic …
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Critical literature review on concrete crack repairs
… techniques include visual inspections, ultrasonic pulse velocity test, acoustic emission, spectral analysis of surface waves, modal analysis, petrographic analysis and infrared thermography. Several concrete crack repair techniques are to be discussed such as epoxy injection, routing and …
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Effect of palm oil waste and quarry dust on the properties of hybrid blocks
… such as the density, compressive strength, ultrasonic pulse velocity (UPV), modulus of rupture, water absorption, a compressive strength of prisms, efflorescence, thermal conductivity, and leachability. Furthermore, the investigation on the durability of the blocks in laboratory accelerated …
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Evaluation and improvement of frost durability of clay bricks
… evaluation of durability was carried out using ultrasonic pulse velocity. New durability provisions were derived based on pulse velocity, using ASTM C216 specifications. At this stage it can be used only along with the ASTM method but it can avoid the time consuming ASTM procedure in many cases. …
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Characterisation of shape of fine recycled crushed coloured glass and the effect on the properties of structural concrete when used as a fine aggregate replacement
… slump, flow, initial and final setting time, ultrasonic pulse velocity, water absorption by immersion and capillarity rise, ASR measurement (volumetric and linear), compression strength at ages from 7 days to 365 days. Techniques of developed digital imaging and processing have been applied to …
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The applicability of recycled waste paper as lightweight building materials
… 0.19 W/m.k thermal conductivity, 989.9 m/s ultrasonic pulse velocity, 0.0026 g/m2.S0.5 average coefficient of capillary water absorption and 883.38 MPa estimated elastic modulus. The approximate compressive strength of 2.38 MPa and 1.58 MPa were respectively predicted and recorded for the …
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Development of Sustainable Masonry Brick
… flexural strength, split tensile strength, ultrasonic pulse velocity, cold as well as hot water absorption, saturation coefficient, efflorescence, freeze thaw damage, and resonant frequency, all being part of the established quality control procedures in this industry. For the HBS-polymer …
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Evaluating The Most Reliable Combination Of Non-Destructive Test Methods For Concrete Uniformity And Relative Compressive Strength.
… concrete beams using the Rebound hammer method, Ultrasonic pulse velocity and Impact Echo methods before coring and 28 days after coring and repair of the two beams. Destructive testing was also conducted through drilling of cores from the RC beams and laboratory testing for compressive strength, …
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Deterioro del hormigón sometido a ensayos acelerados de hielo-deshielo en presencia de cloruros
… sensores de fibra óptica. La velocidad de pulso ultrasonico (VPU) en las probetas de hormigón también se ha medido utilizando diferentes métodos y equipos para establecer la variación del modulo de elasticidad dinámico del material. El trabajo presenta los resultados correspondientes a los …
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Sustainable Utilisation of Raw Sewage Sludge (RSS) as a Water Replacement in Cement-Based Materials Containing Unprocessed Fly Ash
… density, Total Water Absorption (TWA), Ultrasonic Pulse Velocity (UPV), compressive strength, flexural strength, drying shrinkage, sulphate attack and leaching properties. Three series of cement-based materials were studied including mortar mixes with RSS and unprocessed fly ash (Series …
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Corrosion performance of coated steel bars in cracked and uncracked reinforced concrete beams
… methods such as Ground Penetrating Radar (GPR), Ultrasonic Pulse Velocity (UPV), and Impact Echo (IE) are employed to assess the long term corrosion condition. Overall, it was observed that through 11 months of cyclic chloride ion exposure that the TEC bar specimens, both loaded and unloaded and …
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The impact of natural and synthetic zeolite when used in cementitious based systems
… were performed, comprising of; specific gravity, ultrasonic pulse velocity, compressive strength testing, scanning electron microscopy, x-ray diffraction and Fourier transform infrared spectroscopy. All test results were determined at ages of two, seven, twenty-eight and seventy curing days. The …
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