Wyniki wyszukiwania - BazTech

1

The effect of selected factors on the hygrothermic condition of walls insulated from the inside

Orlik-Kożdoń Bożena

Materiały Budowlane

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2025

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nr 4

47--54

EN

The article presents selected issues related to the hygrothermal design of insulated wall systems from the inside. The presented issues concerned the influence of specific factors on changes in the moisture content of insulated partition materials over time. These included: external environmental conditions (driving rain, orientation, location and others), internal climate (different moisture load), moisture of the existing wall and the thickness of thermal insulation and the method of defining it.

PL

W artykule przedstawiono wybrane zagadnienia dotyczące projektowania higrotermicznego układów ściennych ocieplanych od wewnątrz. Prezentowana problematyka dotyczy wpływu określonych czynników na zmianę zawilgocenia materiałów izolowanej przegrody w czasie. Należały do nich: warunki środowiska zewnętrznego (zacinający deszcz, orientacja, lokalizacja i inne), klimat wewnętrzny (zróżnicowane obciążenie wilgocią), zawilgocenie istniejącego muru oraz grubość izolacji termicznej i sposób jej definiowania.

2

Quantitative effects of thickness and coarse-grained sand additive on soil cracking through crack parameters

Vo Dai Nhat

Inżynieria Mineralna

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2025

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Vol. 2, no. 1

217--226

EN

In this paper, an attempt was made to evaluate the effects of thickness and coarse-grained sand additive on cracking of Kaolinite clay using digital image processing (DIP). To minimize the errors which can occur in using DIP, control point selection (CPS) technique was applied. To determine the quantity of soil cracking, images of cracked soil after converting to binary were used to quantify crack parameters by automatically applying a written program. The measurements showed that the variation of most crack parameters is described as a power function of thickness with the high regression coefficient, more than 0.99, except area of fracture, by using the fitting curve method. In addition, the variations of length of cracks, width of cracks, area of cracks, number of pattern and number of fractures are inversely proportional while those of characteristic distance as well as mean cell area are directly proportional to the percentage of coarse-grained sand additive.

3

Analysis of transitional stresses in non-local thermo-elastic disc under steady state temperature

Ailawalia P., Kumar A., Kaur J., Jurczak P.

International Journal of Applied Mechanics and Engineering

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2025

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Vol. 30, no. 2

1--19

EN

In solid mechanics, there are various applications of non-local theories in wave propagation, size effects, surface effects, and understanding interactions of composite materials. There are certain parameters associated with rigid bodies like stress, angular speed, and displacement which show variation with changes in temperature, thickness, density, and media. This study focuses on the evaluation of stresses, angular speed, and displacement that occur in elastic thin rotating discs. The use of local theories only investigates the effect of stress at a point that occurred due to strain at the same point. However using the non-local approach, the variation in the stresses at distant points in a material can be analyzed. This would be a significant work to understand the microstructural material characteristics. Hence this study focuses on providing a more accurate stress model for non-local thin rotating discs. The developed model for rubber, copper, and aluminum material discs is tested, to investigate the above parameters in non-local media. Further, the graphical analysis of angular speed, stresses, and displacement have been shown separately by taking k=0 and k≠0 in non-local media.

4

Prediction of the spring back of AA5052 under a variety of parameters through the use of artificial neural network and finite element analysis

Mohammed Atheer R., Abdalhussien Eman S.

Advances in Science and Technology. Research Journal

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2025

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Vol. 19, no. 11

367--381

EN

Bending is a commonly utilized method in the manufacturing of aluminum components. Spring back is a well-known problem in sheet metal forming that reduces operating efficiency and compromises dimensional precision. The Predicting the part's ultimate shape after spring back and designing tooling to adjust for it remains a practical concern in the manufacturing business. Using available finite element analysis (FEA) and Artificial Neural Network (ANN), this paper predicts the spring back of AA5052 under various variables. The results demonstrate that the spring back phenomenon is significantly influenced by the thickness of AA5052 and the angle of rolling. Following the thickness of AA5052, which accounts for 38.7% of the overall variance, angle of rolling, representing 32.3% of the total variation, is the procedure-dependent variable. The maximum spring back value was 10.5 at the thickest (2 mm) and the minimum was 3.5 at the thinnest 1 mm thickness in practice. The SB findings were analyses by comparing experimental, FEA, and ANN values. The ANN model exhibited a minimum SB of 3.488 with an error of 0.3%, whereas the FEA model demonstrated a minimum SB of 3.447 with an error of 1.56%. In this context, the ANN model is proficient in rapidly forecasting spring back, lowering analysis time, minimizing errors, lowering cost, and expediting product success.

5

Mechanical properties and fracture behavior of sandstone similar materials with different joint positions and thicknesses based on triaxial testing and PFC simulation

Jing Wei, Lu Bingpeng, Jing Laiwang, Jin Rencai

Archives of Civil Engineering

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2024

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Vol. 70, nr 4

615--629

EN

The mechanical properties and failure characteristics of joined rocks have an important impact on the disaster prevention of underground engineering and the sustainable development of mineral resources. The effects of confining pressure, joint location, and joint thickness on the mechanical properties of rock-like specimens under triaxial test have been studied. Furthermore, using the "DFN-age" function of PFC numerical simulation, the stress characteristics, and failure characteristics of rock specimens under different confining pressure, joint location and joint thickness are analyzed. The research results indicate that as the thickness of the joint increases and the joint position approaches the center of the specimen, the compressive strength of the specimen decreases. As the confining pressure increases, the compressive strength increases and failure modes of rock like specimens with different joint types also tend to be similar. The specimens manifest complex shear-tensile composite failures. In addition, the initiation cracks and main control cracks at the joint terminus can be classified as reverse tensile wing cracks, reverse shear cracks, shear cracks and tensile wing cracks. When the joint thickness of the specimen is 1.0 mm and the distance from the joint position to the center of the specimen is 10-20 mm, the crack evolution characteristics and stress distribution law of the specimen will undergo a transformation.

6

Laser Ultrasonic Technique for Simultaneous Measurement of Thickness, Slope, and Wave Velocities for Slope Plate in the Thermoelastic Regime

Dung Nguyen Tien, Arai Yoshio

Advances in Science and Technology. Research Journal

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2024

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Vol. 18, no. 5

217--233

EN

This study introduces a reliable method for simultaneously determining the thickness, slope, and ultrasonic velocities of slope plates using laser ultrasonic techniques without any damage in the thermoelastic regime. The method involves solving a system of equations to determine the arrival times of multiple signals displayed on a waveform. Numerical simulations indicate that the velocity of the skimming longitudinal wave remains constant when the Rayleigh wave does not overlap with its signal. Consequently, a prediction model for aluminum alloy has been established, enabling the estimation of the constant ratio between the velocities of skimming longitudinal and bulk longitudinal waves based on the skimming longitudinal velocity obtained by scanning the generating laser along the material's surface. This ratio, approximately 0.950, facilitates the combination of the skimming longitudinal wave with the reflected and mode-converted waves from the specimen's back surface to deduce the desired parameters. The method successfully determined the thickness, slope, and wave velocities of several specimens with slopes ranging from 0% to 1.96% and a maximum thickness of about 10 mm. Evaluating the influence of the size of the disk ultrasound source produced by the unfocused laser beam, we found that the radius of the disk source should be considered when calculating the arrival time of the skimming longitudinal wave. The root mean square deviation in measuring thickness, slope, longitudinal wave velocity, and shear wave velocity were approximately 0.100 mm, 0.10 %, 70 m/s, and 20 m/s, respectively. An assessment of the measured results, based on the root mean square deviation and uncertainty across all specimens, demonstrates the practical feasibility of the proposed method.

7

Rock typing and uncertainty assessment in geological and petrophysical properties by integrating electrofacies, hydraulic flow units, and geostatistical techniques in the Kangan gas field, Zagros basin

Bakhtiyari Mohammad, Qajar Jafar, Karimian Torghabeh Amir, Dehghan Abnavi Ali

Acta Geophysica

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2024

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Vol. 72, no. 4

2323--2347

EN

The structural complexities of hydrocarbon reservoirs make it difficult to correlate geological and petrophysical properties. A successful field development depends on accurately mapping the spatial distributions of reservoir key parameters. In this study, we present results on rock type analysis, estimation, and uncertainty evaluation of geological and petrophysical data of 33 wells in one of the south Iranian gas fields. This paper is divided into two parts. In the first part, we used a reservoir rock classification theme based on identifying electrofacies (EFs) and hydraulic flow units by analyzing both log and core data. In the second part of the paper, we performed estimation, uncertainty evaluation, and assessment of the porosity-thickness relationship of the high-quality EFs using geostatistical techniques. We used sequential simulation schemes to map the spatial distributions of porosity and thickness of the high-quality EFs across the field. Using probabilistic approaches, the generated multiple realizations were used to quantify the local and spatial uncertainties. Variogram analysis showed that property distributions had a higher continuity and minimum variance in the NW-SE direction. Based on spatial uncertainty analysis, we found that the indicator-based sequential simulated maps exhibited less spatial uncertainty. Furthermore, the obtained probability maps indicated that the SE part of the study area is more suitable for drilling and production scenarios.

8

Różnorodność pap asfaltowych wraz z przykładowymi metodami oceny przydatności do stosowania w pokryciach dachowych

Francke Barbara

Materiały Budowlane

|

2023

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nr 6

43--47

9

The influence of selected plasma spraying parameters on microstructure and porosity of molybdenum coating

Kubaszek Tadeusz, Zgódka Patrycja, Słyś Anita, Góral Marek, Drajewicz Marcin

Ochrona przed Korozją

|

2022

|

nr 10

321--315

EN

Thermal sprayed molybdenum coating is widely used to decrease friction coefficient of machine components. Currently, many methods are used to fabricate it on steel substrate, e.g. arc spraying, plasma spraying, flame spraying and supersonic spraying. The article presents a preliminary study on the influence of basic plasma spraying parameters using an A60 plasma torch on thickness and porosity of molybdenum coating. The investigated basic parameters were: plasma gasses flow rate (Ar/H2 ratio: 64/7, 67/4, 61/10 NLPM, normal liters per minute), power current (550, 650, 750 A) and powder feed rate (10, 20, 30 g/min) was established. The obtained results showed that the A60 plasma torch could be used to deposit molybdenum coatings with the thickness achievable by other similar plasma spraying equipment. However, the porosity of deposited molybdenum coatings were higher than that obtained by other thermal spraying processes such as HVOF.

PL

Powłoki molibdenowe są powszechnie wykorzystywane w celu zmniejszenia współczynnika tarcia elementów maszyn. Obecnie stosowanych jest wiele metod natryskiwania cieplnego do wytwarzania takich powłok na podłożu stalowym, m.in.: natryskiwanie łukowe, plazmowe, płomieniowe i naddźwiękowe. W artykule przedstawiono wyniki wstępnych badań nad wpływem podstawowych parametrów natryskiwania plazmowego z użyciem palnika plazmowego A60 na grubość i porowatość powłok molibdenowych. Podstawowymi analizowanymi parametrami były: natężenie przepływu gazów plazmotwórczych (wartości natężenia przepływu Ar/H2: 64/7, 67/4, 61/10 NLPM), natężenie prądu palnika (550, 650, 750 A) oraz natężenie podawania proszku (10, 20, 30 g/min). Uzyskane wyniki wskazują, że zastosowanie palnika plazmowego typu A60 pozwala na uzyskanie powłok molibdenowych o porowatości i grubości zbliżonej do tych, które charakteryzują powłoki wytwarzane za pomocą innych podobnych systemów do natryskiwania plazmowego, jednak porowatość uzyskanych powłok molibdenowych jest wyższa od wytwarzanych w innych procesach natryskiwania cieplnego, np. naddźwiękowego HVOF.

10

Wpływ gęstości wełny mineralnej na izolacyjność w warunkach pożarowych

Sulik Paweł

Materiały Budowlane

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2022

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nr 7

8--10

PL

W artykule przedstawiono wyniki badań laboratoryjnych wpływu dziesięciu typów skalnej wełny mineralnej o różnej gęstości na zdolność izolowania oddziaływań termicznych wywołanych pożarem. Gęstość badanej wełny mineralnej wynosiła 28 - 170 kg/m3, a grubość 50, 100, 150 i 200 mm. Badania potwierdziły, że istnieje zależność pomiędzy zdolnością do izolowania przed temperaturą pożarową a gęstością wełny mineralnej, przy czym zaobserwowano, że w wielu przypadkach wystarczy zastosowanie wełny mineralnej o małej gęstości i odpowiedniej grubości, aby uzyskać oczekiwany poziom bezpieczeństwa pożarowego przegrody.

EN

The paper presents the results of laboratory tests for 10 types of rock mineral wool with different density in the field of fire temperature insulation. The results include densities from 28 to 170 kg/m3, and thicknesses of mineral wool of 50, 100, 150 and 200 mm. The tests confirmed the dependence of the density of mineral wool on the effectiveness of insulating fire temperatures, and it has been observed that in many cases it is enough to use mineral wool with a lower density and proper layer thickness to obtain the expected fire safety level of the partition.

11

Stress-strain state simulation of non-uniformly heated elements of components and assemblies of automotive

Hrevtsev O., Selivanova N., Popovych P., Poberezhny L., Brych V. Ya., Rudyak Yu., Shevchuk O., Bakulina N., Rozum R., Buriak M.

Journal of Achievements in Materials and Manufacturing Engineering

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2022

|

Vol. 115, nr 1

26--32

EN

Purpose: Develop a method for determining and evaluating the stress-strain state, particularly the distribution of thermomechanical stresses in the materials of individual rotating parts of vehicles. Design/methodology/approach: The proposed method is based on the principle of gradual approximations of the solution when the boundary conditions are satisfied on the curvilinear limiting surfaces of the disk body. Findings: The proposed method of determining and estimating the distribution of thermomechanical stresses in the disk material makes it possible to take into account the variable geometry: thickness and presence of a hole in the central part of the disk, also correctly determine stress-strain state at any point of unevenly heated rotating axial body. Research limitations/implications: The work uses generally accepted assumptions and limitations for thermomechanical calculations. Originality/value: It is proved that in real disks, the stress-strain state is spatial, and the well - known method based on the hypotheses of the plane-stress state does not provide the possibility of calculating the values of stresses in the thickness of the disk. The obtained results can be used to improve the methodology of auto technical examination of road accidents. In addition, they can be taken into account by bus drivers on urban routes when choosing a safe distance in heavy traffic, as well as design engineers of car brake systems.

12

Determination of the optimal frequency of the primary measuring transducer of the thickness of dielectric coatings of metal surfaces

Ovchynnykov Kostyantyn V., Vasilevskyi Oleksandr M., Sevastianov Volodymyr M., Polievoda Yurii A., Kalizhanova Aliya, Yeraliyeva Bakhyt

Informatyka, Automatyka, Pomiary w Gospodarce i Ochronie Środowiska

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2022

|

T. 12, nr 2

56--59

EN

The article provides an analysis of the physical processes underlying the operation of the measuring transducer, with a time based information presentation. A mathematical model is developed that describes the process of free oscillation attenuation excited in the LC-contour of primary measuring transducer, and analyzes and evaluates the influence of external factors that influence the measurement results. The ways of elimination of their influence on the results of measuring control are offered.

PL

Artykuł zawiera analizę procesów fizycznych leżących u podstaw pracy przetwornika pomiarowego wraz z prezentacją informacji w czasie. Opracowano model matematyczny opisujący proces tłumienia drgań swobodnych wzbudzanych w obwodzie LC głównego przetwornika pomiarowego, analizujący i oceniający wpływ czynników zewnętrznych na wyniki pomiarów. Proponowane są sposoby wyeliminowania ich wpływu na wyniki kontroli pomiarów.

13

Investigation of Twist Waves Distribution along Structurally Nonuniform Yarn

Shukhratov Sh., Milašius R., Gafurov K., Gafurov J.

Autex Research Journal

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2022

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Vol. 22, no. 4

488--492

EN

This paper presents the features of yarn structure formation on spinning machine, i.e. yarn twist change when winding. It was considered that the twist distribution was one of the reasons for its decrease along the formed yarn. In this paper, based on analysis of changes in thickness and twist due to axial deformation, we consider a yarn moving at constant speed. Moving dynamics of yarn are studied here by using Euler variables. The correspondences of forward and reverse twist waves’ distribution speeds on presented frequency at various vibration forms are obtained. The parameters of Doppler effect for the waves distributed along the yarn are determined.

14

The influence of densification time on the tensile strength and modulus of elasticity of birch veneers

Słupecki Adam, Wronka Anita

Annals of Warsaw University of Life Sciences - SGGW. Forestry and Wood Technology

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2022

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No. 118

48--54

EN

The influence of densification time on the tensile strength and modulus of elasticity of birch veneers. The aim of the following study was to examine and compare tensile strength, modulus of elasticity, and thickness of birch (Betula pendula Roth) veneers modified by thermomechanical densification. Birch veneers were densified at the temperature of 100 °C at different times (ranges from 10 to 60 minutes). Tensile strength was tested longitudinally to the grain. As a result of this study change in tensile strength was observed for 60 minutes of densification. The rise in modulus of elasticity was also observed for 10, 20, 30, 50, and 60 minutes. The thickness of wooden veneers was changed significantly for each densification time.

PL

Wpływ czasu zagęszczania na wytrzymałość na rozciąganie i moduł sprężystości fornirów brzozowych. Celem badań było określenie wybranych właściwości mechanicznych zagęszczonych fornirów z drewna brzozowego (Betula pendula Roth). W ramach badań przeprowadzono badanie wytrzymałości na rozciąganie wzdłuż włókien, a także modułu sprężystości oraz analizę zmiany grubości. Wyniki wskazują, że wytrzymałość na rozciąganie wzrosła znacząco dla próbek zagęszczanych przez czas 60 minut. Zaobserwowano również wzrost wartości modułu sprężystości dla próbek zagęszczanych przez okres 10, 20, 30, 50 i 60 minut. Zaobserwowano znaczącą zmianę grubości dla wszystkich czasów zagęszczania.

15

Differences in thickness variations of activated carbon in decreasing oil and grease levels using modified grease trap on the canteen wastewater

Fikri Elanda, Hanifati Dhaifina, Hidayah Nurul

Przegląd Naukowy Inżynieria i Kształtowanie Środowiska

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2021

|

Vol. 30, No. 1

106--116

EN

Wastewater is residual water of industrial activities and domestic wastewater that is derived from daily activities of human life related to water usage, such wastewater should not be discharged into water bodies if it has not met the standards based on the regulation. Oil and grease contained in the water bodies will form a layer on the surface because the density of oil is lower than the density of water. The layer of oil and grease will block the entry of sunlight and cause the inability in the photosynthesis process of aquatic plants. The textile industry facilitates canteens within the company which operates daily at 11.00–13.00 Western Indonesian Time, resulting in the domestic wastewater from the canteen kitchen activities. The purpose of this study was to determine differences in the thickness variations of activated carbon to reduce oil and grease levels using modified grease traps on the canteen wastewater at PT. Sipatex Putri Lestari. The type of study used was categorized as a field experiment with a pretest–posttest research design. The population of the study was the entire canteen wastewater of PT. Sipatex Putri Lestari. The sampling technique used the time composite method. The univariate analysis of the study showed the average number of decreases in oil and grease levels in the treatment as 12.32, 15.98 and

16

Comparative Study on the Properties of Taped Seams with Different Constructions

Kara Sukran, Yeşilpınar Sevil

Fibres & Textiles in Eastern Europe

|

2021

|

Vol. 29, no. 2 (146)

54--60

EN

Ready to wear end-products may be obtained by different assembling methods such as sewing, bonding, seam taping, welding and pressing fabrics. Currently, sewing is the most common method, but other techniques are improving day by day in accordance with the new application areas and new requirements from seamlines. Seam taping is an innovative alternative method that can improve the properties of seams. In this study, some essential properties such as the strength, elongation, thickness and air permeability of sealed samples with different constructions were compared. As taping constructions, ultrasonic bonding plus taping, sewing plus taping, and only taping methods were used. These methods were varied according to the taping temperature and speed. Also, only sewn and ultrasonically bonded samples were prepared as reference samples. In total, 20 different kinds of seam sealed samples were obtained as test materials. According to the results, taped samples were advantageous in terms of seam thickness and seam strength properties when compared to only sewn and ultrasonically bonded references. Especially, "only taped" samples were one step ahead among the all constructions. The air permeability of the taped seams decreased by a certain amount, but it is thought to be tolerable in a full garment.

PL

Gotowe do noszenia produkty końcowe można otrzymać różnymi metodami łączenia, takimi jak: szycie, podklejanie, zgrzewanie i prasowanie tkanin. Obecnie szycie jest najpowszechniejszą metodą, ale inne techniki są z dnia na dzień udoskonalane zgodnie z nowymi obszarami zastosowań i nowymi wymaganiami dotyczącymi szwów. Podklejanie szwów to innowacyjna, alternatywna metoda, która może poprawić właściwości szwów. W badaniu porównano niektóre istotne właściwości, takie jak: wytrzymałość, wydłużenie, grubość i przepuszczalność powietrza próbek o różnych konstrukcjach. Jako konstrukcje z taśmami zastosowano klejenie ultradźwiękowe plus taping, szycie plus taping i tylko taping. Metody te były zróżnicowane w zależności od temperatury i prędkości taśmowania. Jako próbki referencyjne przygotowano również próbki szyte i wiązane ultradźwiękowo. W sumie uzyskano 20 różnych rodzajów próbek zgrzewanych jako materiały testowe. Zgodnie z wynikami próbki oklejone taśmą były korzystne pod względem grubości szwu i właściwości wytrzymałości szwu w porównaniu z wzorami zszywanymi i łączonymi ultradźwiękowo. W szczególności próbki „tylko zaklejone” były o krok przed wszystkimi konstrukcjami. Przepuszczalność powietrza w szwach klejonych zmniejszyła się o pewną wartość, ale uważa się, że może być to tolerowane.

17

Effect of the thickness to length ratio on the frequency ratio of nanobeams and nanoplates

Bahrami Arian, Shiri Hamidreza, Khosravi Nima

Journal of Theoretical and Applied Mechanics

|

2020

|

Vol. 58 nr 1

87--96

EN

This communication presents the effect of thickness on the frequency ratio of nanobeams and nanoplates using Eringen’s nonlocal theory. Although there exist numerous works regarding the effects of thickness and small scale on the frequency ratio of nanobeams and nanoplates, none has captured and reported the true effects. The main intention of this communication is to correct the misunderstanding regarding this issue. It was found that the frequency ratio is indeed dependent on the thickness to length ratio and its variation with respect to thickness to length ratio is highly dependent on the mode number, combination of boundary conditions, plate aspect ratio, and the nonlocal parameter.

18

Influence of the Thickness of Graphene Coating on the Electromagnetical and Mechanical Properties of Double-Layer Coated Basalt Fibre Fabrics

Liu Yuanjun, Yang Yanfeng, Yang Zhanhua, Liu Yanyan, Su Ying, Niu Jiarong

Fibres & Textiles in Eastern Europe

|

2020

|

Vol. 28, no. 5 (143)

69--74

EN

A double-layer coated basalt fibre fabric was prepared using polyurethane as the matrix and applying coating technology to the basalt fibre fabric. The influence of the thickness of the graphene coating on the electromagnetic properties and mechanical properties of the double-layer coated basalt fibre fabric was studied. Results showed that when the thickness of the graphene coating was 2.0 mm, the polarising ability, loss ability and attenuating ability of the fabric with respect to electromagnetic waves were all the largest. Along with the increasing thicknesses of the graphene coating, the electromagnetic shielding effectiveness of the double-layer coated basalt fibre fabric also increased, then the shielding ability against electromagnetic waves became stronger.

PL

W pracy przygotowano dwuwarstwowo powlekaną tkaninę z włókna bazaltowego, stosując poliuretan jako matrycę i stosując technologię powlekania na tkaninę z włókien bazaltowych. Badano wpływ grubości powłoki grafenowej na właściwości elektromagnetyczne i mechaniczne dwuwarstwowo powlekanej tkaniny bazaltowej. Wyniki pokazały, że gdy grubość powłoki grafenowej wynosiła 2.0 mm, polaryzacja, zdolność do strat i zdolność tłumienia tkaniny w odniesieniu do fal elektromagnetycznych były największe. Wraz ze wzrostem grubości powłoki grafenowej wzrastała również skuteczność ekranowania elektromagnetycznego dwuwarstwowo powlekanej tkaniny bazaltowej z włókien bazaltowych, a następnie zdolność ekranowania przed falami elektromagnetycznymi stała się silniejsza.

19

Estimation of the adherence of mortars using ultrasound

Khaldi Nacera, Belachia Mouloud, Benouis Abdelhalim

Civil and Environmental Engineering Reports

|

2020

|

Vol. 30, no. 2

185--199

EN

Mortars are subjected to severe external stresses such as freezing, thawing, and drying during their lifetime. These stresses can lead to a loss of adhesion between the support and the mortar. The strength of the substrates with respect to their ability to receive a coating (mortar) is characterized in particular by the value of minimum tear resistance of the surface to be coated. In this work, the use of a non-destructive method which is both fast and easy to implement is employed to evaluate this support-mortar adhesion. The first method is based on the measurement of the velocities of the surface ultrasonic waves and the second by tearing tests using a specific dynamometer. The determination of the adhesion strength concerned two different supports (concrete beam and masonry block) coated with two types of mortar (a prepared cement mortar and a ready-to-use mortar) with two different thicknesses for each mortar (1 and 2 cm, respectively). The results of the two methods are then correlated for an estimation of the adhesion of the mortars.

20

Numerical study of a cracked pipeline under internal pressure

Abderraouf Khireche, Zohra Labed

Archives of Mechanical Technology and Materials

|

2020

|

Vol. 40

30--33

EN

In the industrial sectors, pipelines have been used as the most economical and safe means of transporting oil and gas (Pipelines). However, the number of accidents has increased considerably as their use has increased. As a result of the operating load and the pressure used, the thickness of the tube must be increased and the mechanical characteristics improved. This approach was applied to predict the growth of crack effect in samples of two pipelines at given thicknesses and pressures. We created cracks with deferential dimensions in both API X80 steel pipelines, with an application of deferential internal pressures. For the simulations, we used the code ANSYS.