Wyniki wyszukiwania - BazTech

1

Analiza pracy poprzecznej łączników prętów jako przykład działań B+R w nowoczesnej prefabrykacji betonowej

Surma Mateusz, Wojciechowski Szymon

Materiały Budowlane

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2022

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nr 3

28--29

2

Characterisation of spoil materials to develop an equivalent spoil material for physical model tests

Garala Thejesh Kumar, Cui Ge, Kantesaria Naman, Heron Charles M., Marshall Alec M., Žižka Lukáš

Górnictwo Odkrywkowe

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2022

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R. 63, nr 4

23--29

EN

The engineering behaviour of spoil (overburden) needs to be explored either to understand the stability of reservoir slopes under various geological and climatic conditions or for the effective utilisation of reclaimed mines for sustainable infrastructure (e.g., onshore wind turbines). The spoil material is usually considered as highly heterogeneous, and samples collected from the same site can exhibit widely varying characteristics. In this study, spoil material from a mine site in the Czech Republic is characterised using in-situ field tests and laboratory tests. Cone penetration tests were performed in the field and sample cores were collected for laboratory testing. In the laboratory, the index and engineering characteristics of the spoil were evaluated. Given the measured characteristics and behaviour of the field spoil, an equivalent spoil is proposed to perform physical modelling tests using geotechnical centrifuge. This enables simulation of the field spoil behaviour in controlled centrifuge testing, from which other aspects of spoil (e.g. stability of spoil slopes, spoil-structure interaction) can be investigated.

PL

Zachowanie zwałowisk pogórniczych (nadkładu) pod względem inżynieryjnym powinno zostać zbadane w celu określenia stabilności zboczy zbiorników poeksploatacyjnych w różnych warunkach geologicznych i klimatycznych lub w celu efektywnego wykorzystania rekultywowanych kopalń do budowy zrównoważonej infrastruktury (np. lądowych turbin wiatrowych). Materiał zwałowisk pogórniczych jest zwykle uważany za wysoce niejednorodny, a próbki pobrane z tego samego miejsca mogą wykazywać bardzo różne właściwości. W niniejszej pracy, materiał odpadowy z czeskiej kopalni został scharakteryzowany przy użyciu badań terenowych i laboratoryjnych in-situ. W terenie przeprowadzono sondowania CPT, a do badań laboratoryjnych pobrano próbki rdzeniowe. W laboratorium oceniono właściwości indeksowe i inżynieryjne materiału. Biorąc pod uwagę zmierzone cechy i zachowanie się materiału pogórniczego, zaproponowano materiał równoważny do wykonania modelowania fizycznego z wykorzystaniem wirówki geotechnicznej. Umożliwia to symulację zachowania się materiału w kontrolowanych badaniach wirówkowych, na podstawie których można badać inne cechy materiałów pogórniczych (np. stabilność skarp zwałowiska, interakcje zwałowisko-konstrukcja budowlana).

3

Experimental study on shear mechanical properties of cement mortar specimen with through-step joints under direct shear

Xiong Liangxiao, Chen Haijun, Guo Haogang, Mei Songhua, Xu Zhongyuan, Liu Bin

Archives of Civil Engineering

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2022

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Vol. 68, nr 4

45--61

EN

In this study, direct shear tests were carried out on cement mortar specimens with single-ladder, single-rectangular, and double-rectangular step joints. Consequently, the shear strength, and crack shape of specimens with these through-step joints were analyzed, for understanding the influence of the through-step joint’s shape on the direct shear mechanical properties. The results of the investigation are as follows: (1) Under the same normal stress, any increases in the height h of the step joint causes an initial-increase-decrease in the shear strengths of specimens with single-ladder and double-rectangular step joints, causing a type-W variation pattern for the specimens with single-rectangular step joint. More essentially, when normal stress and h are constant, the shear strength of specimens with a single-ladder step joint is the greatest, followed by specimens with a double-rectangular step joint, and then specimens with a single-rectangular step joint is the least. (2) Furthermore, given a small h and low normal stress, specimen with a single-ladder step joint mainly experiences shear failure, whereas specimens with single-rectangular and double-rectangular step joints mainly generate extrusion milling in the step joints.

4

Soft computing approaches for comparative prediction of ram tensile and shear strength in aluminium–stainless steel explosive cladding

Saravanan S., Gajalakshmi K.

Archives of Civil and Mechanical Engineering

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2022

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Vol. 22, no 1

art. no. e42, 2022

EN

This study deals with the application of soft computing techniques viz., response surface methodology, artificial neural network, radial basis function network and support vector regression in analyzing and predicting the ram tensile and shear strengths of aluminium 5052–stainless steel 316 explosive clads, having different interlayer. 60 explosive cladding experiments were conducted, based on central composite design of experiments, by varying the process parameters viz., loading ratio (mass of the explosive/mass of the flyer plate: 0.6–1.0), distance of separation (6–10 mm), preset angle (6°–8°) and interlayer (aluminium 1100/pure copper/stainless steel 304). The responses viz., ram tensile and shear strengths obtained from 90% of the experiments and trial experiments are used for training artificial neural network, radial basis function network and support vector regression in a Matlab environment, altering training algorithms and number of neurons in the hidden layer. The remaining 10% of the experimental outcome is used for testing the developed models. Likewise in RSM, regression equations are generated for the responses, based on analysis of variance. All the four models are capable of predicting the ram tensile and shear strength effectively, as the average percentage deviation with the experimental outcome are less than 10%. Of the three models, artificial neural network model predicts the ram tensile strength and shear strength in a better manner.

5

Moisture influence on solid wood bonded with modified starch

Bartoszuk Katarzyna, Kowaluk Grzegorz

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

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2022

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No. 118

67--73

EN

Moisture influence on solid wood bonded with modified starch. A growing and developing population is contributing to the ever-increasing global warming, which is caused, among other things, by the heavy use of chemicals. Most of them are crude oil-based, which is a non-renewable source. That is why the population tries to find organic substitutes in every area, even in the wood industry. Here, the most common and popular binders - amine resins, are subjected in research to partial or full replacement by more natural binders, non-formaldehyde, made of renewable raw materials, preferably plant-based. In this project, the studies were carried out on the possibility of starch-based glue application in wood bonding and its effect on glued birch wood (Betula pendula Roth) under various environmental storage conditions of bonded samples (0%, 65%, and 100% of RH). The results show, that the samples at room temperature and normal humidity, as well as another – additionally dried, have a very similar shear strength. In-wood damages, on the other hand, are much more varied. The research also included moistened samples, which gave poorer results (about 12% lower than the remaining samples). Based on the results, it can be concluded, that modified starch is a very good organic glue, that can potentially replace some chemical products in certain applications.

PL

Wpływ wilgoci na drewno lite sklejone skrobią modyfikowaną. Przeprowadzono badania nad możliwością zastosowania kleju skrobiowego w spajaniu drewna i jego wpływem na klejone drewno brzozowe (Betula pendula Roth) w różnych warunkach środowiskowych przechowywania sklejonych próbek. Wyniki pokazują, że próbki w temperaturze pokojowej i normalnej wilgotności, a także inne – dodatkowo wysuszone, mają bardzo zbliżoną wytrzymałość na ścinanie. Z drugiej strony uszkodzenia drewna są znacznie bardziej zróżnicowane. Badaniami objęto również próbki nawilżane, co dało gorsze wyniki. Na podstawie uzyskanych wyników można stwierdzić, że skrobia modyfikowana jest bardzo dobrym klejem organicznym, który potencjalnie może zastąpić niektóre produkty chemiczne w szczególnych zastosowaniach.

6

Influence of Adhesive Compound Viscosity on the Strength Properties of 1.0503 Steel Sheets Adhesive Joints

Miturska-Barańska Izabela, Rudawska Anna

Advances in Science and Technology. Research Journal

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2022

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Vol. 16, no 2

196-205

EN

The presented study concerned the comparison of the adhesive joints strengths of 1.0503 carbon steel sheets of higher quality, which were made using adhesive compounds characterized by different viscosity index of the components. Three types of commercial epoxy resins were used: Epidian 5, Epidian 53 and Epidian 57, as well as two types of curing agents: polyamide (PAC) and amine (Z-1). The surfaces of the test specimens were subjected to a pre-treatment operation in the process of a mechanical machining with an abrasive coated tool of P320 gradation. The surface roughness measurements were carried out as a control. The single-lap adhesive joints were the subject of the strength testing. The strength tests carried out on a Zwick/Roell Z150 testing machine concerned the comparison of the strength of the adhesive joints loaded in shear. Statistical analysis was performed on the results obtained. It was observed, among others, that the adhesive joints prepared with the epoxy adhesive compounds containing the polyamide curing agent showed much higher the shear strength than the adhesive joints made with the epoxy adhesive compounds containing the amine curing agent. Moreover, the use of the polyamide curing agent in the adhesive compounds with the epoxy resins resulted in formation of a more elastic adhesive layer, for which higher elongation was observed than in the case of the epoxy compound with the amine curing agent.

7

Mathematical model for friction stir lap welded AA5052 and SS304 joints and process parameters optimization for high joint strength

Chitturi Veerendra, Pedapati Srinivasa Rao, Awang Mokhtar

Advances in Materials Science

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2022

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Vol. 22, nr 1(71)

5--22

EN

Due to the numerous challenges faced during the dissimilar welding, choosing the right process parameters and their optimization yields better results. In this context, the current investigation is focused on the optimization of process parameters. Taguchi's L9 orthogonal array was selected to carry out the experimental investigations. The welded samples were tested for shear strength, and the results were analysed using Taguchi's S/N ratio analysis with "larger the better" criteria. Log-linear regression analysis was applied to formulate an empirical correlation between the process parameters and shear strength. According to S/N ratio analysis, the tool rotational speed of 800 rpm, welding speed of 20 mm/min and a penetration depth of 4.1 mm are the optimized parameters that achieve high joint strength. The achieved joint strength was 3.46 kN that is 70% of the base aluminium metal. It was noticed from the Analysis of variance of the regression model that penetration depth and tool rotational speed are the significant contributors with p-values less than 0.5. Confirmation tests show that the error between the predicted and calculated shear strength is 2.06% which is considered acceptable. R2 and adjusted R2 values of the model with a standard error of 0.076 show that the developed model is statistically significant.

8

Effect of the surface treatment on the strength of the single-lap adhesive joints

Doluk Elżbieta, Rudawska Anna, Stančeková Dana

Technologia i Automatyzacja Montażu

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2021

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nr 1

18--22

PL

W artykule przeanalizowano wytrzymałość na ścinanie jednozakładkowych połączeń klejowych wykonanych z ocynkowanej powłoki blachy stalowej. Obróbkę mechaniczną próbek przeprowadzono przy użyciu papierów ściernych P120, P180, P220, P400 i P600. W eksperymencie zastosowano dwa warianty obróbki powierzchni: z odtłuszczaczem i bez odtłuszczacza. Do wykonania połączeń użyto dwuskładnikowego kleju epoksydowego Epidian 53/IDA/100:40. Badania wytrzymałościowe przeprowadzono na maszynie wytrzymałościowej Zwick/Roell Z150, norma PN-EN 1465. W artykule zamieszczono również wyniki pomiaru siły maksymalnej oraz wartości parametrów chropowatości powierzchni (Ra, Rz, Rq) próbek przygotowanych bez odtłuszczacza. Pomiary parametrów chropowatości powierzchni (Ra, Rz, Rq) wykonano przy użyciu profilometru HOMMEL TESTER T1000, zgodnie z normą PN-EN ISO 4287. Maksymalną wartość wytrzymałości na ścinanie (2,70 MPa) uzyskano dla próbek przygotowanych papierem ściernym P220 z użyciem odtłuszczacza, a najmniejszą (1,02 MPa) dla próbek przygotowanych papierem ściernym P180 z użyciem odtłuszczacza.

EN

The paper analyzed the shear strength of the single-lap adhesive joints made of zinc galvanized coat of steel sheet. Mechanical treatment of the samples was carried out using P120, P180, P220, P400 and P600 abrasive papers. In the experiment were used two variants of surface treatment: with a degreaser and without a degreaser.A two-component epoxy adhesive Epidian 53/IDA/100:40 was used to make the joints.The strength tests were carried out on a Zwick/Roell Z150 testing machine, PN-EN 1465 standard. The article contains also the results of the maximum force and the values of the surface roughness parameters (Ra, Rz, Rq) of the samples prepared without a degreaser. The measurements of surface roughness parameters (Ra, Rz, Rq) were made using a HOMMEL TESTER T1000 profilometer, according to PN-EN ISO 4287. The maximum value of the shear strength (2.70 MPa) was obtained for the samples prepared with P220 abrasive paper using a degreaser and the lowest (1.02 MPa) for the samples prepared with P180 abrasive paper using a degreaser.

9

Experimental study on earth pressure reduction of waste tyre bales used as a backfill for rigid retaining structures

Duda Aleksander, Siwowski Tomasz

Studia Geotechnica et Mechanica

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2021

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Vol. 43, nr 4

411-424

EN

Waste tyre-derived products, including whole tyres, tyre bales, shreds, chips and crumb rubber, have been widely used in geotechnical applications. In particular, tyre bales have considerable potential for use in the construction of a lightweight embankment or road foundation over soft ground, slope stabilisation or landslide repairs and the backfilling for retaining structures. Proper design of tyre bale structures requires a reliable strength analysis to ensure an adequate factor of safety. The analysis should utilise the properties of the tyre bales and the baled structures, which must be properly determined. A laboratory test programme was developed to determine the key strength parameters of a backfill made of tyre bales supplemented with a lightweight aggregate. Full-scale direct shear tests were conducted to define the interface shear strength between the tyre bales and the filling material. Earth pressure reduction analysis based on the experimental results was performed as well to assess the effectiveness of waste tyre bales used as a backfill for rigid retaining structures.

10

Shear performance of reinforced self-compacting concrete beams incorporating steel and polypropylene fibers

Alkhattat Saja S., Al-Ramahee Munaf A.

Przegląd Naukowy Inżynieria i Kształtowanie Środowiska

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2021

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Vol. 30, No. 4

537--551

EN

The impact of steel and polypropylene fibers on the performance of lightweight self-compacting concrete (LWSCC) beams was investigated in this study. Seven beams with various parameters were cast and tested. Partial (50%) and full (100%) replacement of coarse aggregate with lightweight aggregate expanded clay (LECA) were considered. In addition, a 1% volumetric ratio of steel or hybrid (steel and polypropylene) fiber was added to LWSCC beams to study their effect on the shear performance. The LWSCC beams had a decrease in ultimate load and stiffness of 23 and 30% for partial and full replacement, respectively when compared to normal weight beam. The addition of steel fiber improved the efficiency of LWSCC beams in terms of crack formation, failure mode, crack width, and ultimate load, as well as changed the failure mode from shear to flexure. The ultimate load for hybrid LWSCC was increased by around 6% for a partial replacement and 13% for full replacement as compared to beams without fibers. However, hybrid beams had a larger bearing capacity, little more cracks with smaller size, and ductile failure.

11

Experimental and finite element analysis of slope stability treated by lime milk (case of El Amir Abdelkader embankment)

Belabbaci Zeyneb, Berrabah Amina, Bouri Djamel Eddine

Mechanics and Mechanical Engineering

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2021

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Vol. 25, nr 1

77--83

EN

This paper presents an experimental stabilization approach of the landslide that threatens a slope located near the city of El Amir Abdelkader, Ain Temouchent, Algeria. Stabilization is assured by the addition of lime milk, and then a numerical validation of the results with respect to the safety coefficient before and after treatment was performer by “Plaxis” software. Experimental results show that the stabilization by lime milk improves compaction parameters, swelling and shear strength, particularly the cohesion and friction angle, the latter permitting appreciation of the sliding surface on which it is necessary to base the calculation of the safety coefficient before and after treatment. Numerical results indicate that the factor of safety increases with the improvement of the mechanical characteristics c and φ, which are improved by increasing lime milk percentage. The numerical validation using “Plaxis” finite element code gives results that are in perfect agreement with the experimental ones, indicating that this software is a good tool for slope stability study.

12

Badanie wpływu zbrojenia poziomego spoin wspornych na wytrzymałość na ściskanie i ścinanie murów z elementów murowych z ABK

Drobiec Łukasz, Jasiński Radosław, Połubiński Tomasz, Mazur Wojciech

Materiały Budowlane

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2021

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nr 8

48--50

PL

W artykule opisano badanie wpływu zbrojenia spoin wspornych na wytrzymałość na ściskanie i ścinanie murów z autoklawizowanego betonu komórkowego (ABK) zgodnie z wytycznymi odpowiednio normy europejskiej EN 1052-1:2000 i amerykańskiej ASTM ES519-81. Zastosowano zbrojenie w postaci pasów siatki rozwijanej z rolki, składającej się z linek stalowych z osnową z włókna szklanego. Wpływ tego typu zbrojenia porównano również z wynikami badań ścian murowanych z ABK bez zbrojenia oraz wzmocnionych odpowiednio zbrojeniem kratownicowym i siatką syntetyczną.

EN

This paper presents a research of influence of horizontal reinforcement on compressive and shear strength of Autoclaved Aerated Concrete (AAC) masonry. Specimens were tested according to guidelines of EN 1052-1:2000 and ASTM ES519-81 code in case of compression and shear test respectively. Reinforcement in the form of strips of mesh rolled out from a roll, consists of steel cords with an interwoven fiberglass roving was used. The influence of this type of reinforcement was also compared with the results of tests of AAC masonry walls without reinforcement, reinforced with truss type reinforcement and reinforced with synthetic mesh respectively.

13

Badanie wpływu wzmocnienia powierzchniowego systemem FRCM na wytrzymałość na ścinanie murów z elementów z autoklawizowanego betonu komórkowego

Drobiec Łukasz, Jasiński Radosław, Mazur Wojciech, Jokiel Remigiusz

Materiały Budowlane

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2021

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nr 5

17--20

PL

W artykule przedstawiono wyniki badań wytrzymałości na ścinanie wzmocnionych powierzchniowo murów z elementów z autoklawizowanego betonu komórkowego (ABK). Stanowią one kolejny etap badań doświadczalnych mających na celu określenie wpływu wzmocnienia powierzchniowego systemem FRCM na wytrzymałość murów z ABK. Badania przeprowadzono wg procedury A zgodnie z wymaganiami normy PN-EN 1052-3 [6]. Program badań obejmował modele wzmocnione z jednej oraz dwóch stron. Uzyskane wyniki porównano z wynikami badań modeli bez wzmocnienia [4].

EN

This paper describes the results from the test of the shear strength of superficial strengthened of walls made of autoclaved aerated concrete (AAC) masonry units. These tests constitute the next stage of experimental research aimed at determining the influence of surface reinforcement with the FRCM system on the strength parameters of AAC walls. The tests were carried out in accordance with the procedure A of PN-EN 1052-3 [6]. The research program included models reinforced on one and two sides. The results were compared with the test results of models without reinforcement [4].

14

Treatment of Collapsible Soils with Granulated Blast Furnace Slag and Calcined Eggshell Waste

Adjabi Souhila, Nouaouria Mohamed Salah, Djebabla Wafa

Civil and Environmental Engineering Reports

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2021

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Vol. 31, no. 2

138--162

EN

In order to meet environmental and socio-economic challenges, the recycling of waste tobe used in the treatment of geotechnical problems is one of the main ways of preserving the environment with a lower economic value. The objective of this experimental work is to improve the characteristics and to study the mechanical behaviour of collapsible soil treated with a new hydraulic stabilizer composed of Crushed Granulated Blast Furnace Slag (CGBS) active by Eggshell Waste (CES). The specimens were mixed with stabilizer content, varying from 0 to 15% in mass, with an initial water content of 4, 6 and 8% respectively. in mass. Oedometer apparatus was used to study the addition of new hydraulic stabilizer effect on the Collapse Potential. Triaxial tests are also conducted to determine the shear strength parameters (cohesion and internal friction angle) of this treated soil. The results of this research study show that the mechanical properties of the treated collapsible soil were significantly improved. An appreciable reduction in the collapse potential is observed. The addition of 15% of this new stabilizer with initial water content of 4% under a compaction of 60 blows/ layer is capable of increasing internal friction angle and cohesion. It can be concluded from this study that the mixture of granulated slag and calcined eggshell can be used as an effective treatment of collapsibility phenomenon at low cost while protecting the environment from industrial waste.

15

Porównawcze badania wytrzymałości na odrywanie od powierzchni międzyfazowej jednorodnego betonu geopolimerowego

Kumar Sumanth B., Seshu Rama D.

Cement Wapno Beton

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2021

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R. 26, nr 1

3--11

PL

Beton geopolimerowy jest kompozytem, który ma potencjalne możliwości aby zostać alternatywnym materiałem dla tradycyjnego betonu. W pracy przedstawiono doświadczenia związane z odrywaniem od powierzchni międzyfazowej jednorodnego betonu geopolimerowego. Sporządzono do doświadczeń 18 próbek do odrywania powierzchni zbrojonych i niezbrojonych, przechodzących przez powierzchnię międzyfazową. Oznaczoną doświadczalnie wytrzymałość na odrywanie betonu geopolimerowgo porównano z wytrzymałością na odrywanie stosując dostępne modele analityczne dla betonu zwykłego. Wyniki doświadczeń wykazały, że wytrzymałość na odrywanie od powierzchni międzyfazowej jednorodnego betonu geopolimerowego, wzrastała do pewnej wytrzymałości na ściskanie tego betonu. Większość dostępnych modeli analitycznych stosują znane metody w ocenie wytrzymałości na odrywanie betonu geopolimerowego.

EN

Geopolymer concrete is the composite and has prospective potential to become one of the alternatives to conventional concrete. This paper presents an experimental investigation on the shear strength of monolithic geopolymer concrete interface. A total of 18 push-off specimens with and without reinforcement across the interface were cast and tested. The experimental shear strength of geopolymer concrete is compared with the shear strength evaluated, using the available analytical models for normal concrete. The test results indicated that the shear strength of monolithic geopolymer concrete interface has increased up to certain compression strength of geopolymer concrete. Most of the available analytical models are conservative in estimating the shear strength of geopolymer concrete.

16

Selection of the test method and its influence on the obtained results of soil strength parameters

Pietrzak Alina, Jura Jakub

Budownictwo o Zoptymalizowanym Potencjale Energetycznym

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2021

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Vol. 10 Nr 2

119--126

EN

The paper presents issues related to the methodology of measuring soil strength parameters. The laboratory methods for determining the shear strength of soil are described, with particular emphasis on the measurement of soil strength using the direct shear method and the triaxial compression apparatus. An attempt was made to determine the impact of the research methodology on the quality of the obtained strength parameters of the soil.

17

Electron beam brazing of austenitic stainless steel AISI 304

Kwieciński Krzysztof, Śliwiński Piotr

Biuletyn Instytutu Spawalnictwa w Gliwicach

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2021

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Vol. 65, No. 2

55--62

EN

Electron beam brazing is a joining technology combining the advantages of a precisely controlled heat source and those of vacuum brazing process. The oxide layer decomposes in high-temperature vacuum conditions, which improves the wetting process and, consequently, leads to the obtainment of more favourable properties of the brazed joint. In comparison with brazing in vacuum furnaces, the electron beam brazing process enables the precise heating of selected areas without the necessity of heating the entire element, which, in turn, results in smaller structural changes in the brazed material and the lower consumption of energy. During tests discussed in this article, sheets made of stainless steel AISI 304 were brazed using various copper and silver filler metals. Brazed joints were subjected to microstructural tests and shear strength tests. The results revealed the high efficiency of the electron beam brazing of corrosion-resistant steel sheets using filler metals.

PL

Lutowanie wiązką elektronów łączy w sobie zalety precyzyjnie sterowanego źródła ciepła, a także prowadzenie procesu lutowania w próżni. W warunkach wysokiej próżni i wysokiej temperatury warstwa tlenków ulega rozkładowi, co poprawia zwilżanie metalu, skutkując lepszymi właściwościami złącza. W porównaniu z lutowaniem w piecach próżniowych, lutowanie wiązką elektronów umożliwia nagrzewanie precyzyjnie wybranych obszarów bez konieczności nagrzewania całego elementu, co skutkuje mniejszymi zmianami strukturalnymi materiału rodzimego i mniejszym zużyciem energii. W niniejszym artykule blachy ze stali odpornej na korozję w gatunku AISI 304 lutowano przy użyciu różnych spoiw na bazie miedzi i srebra. Połączenia lutowane poddano badaniom mikrostruktury, a także próbie wytrzymałości na ścinanie. Wyniki badań potwierdzają dobrą jakość lutowania wiązką elektronów blach ze stali austenitycznej odpornej na korozję przy użyciu zastosowanych spoiw.

18

The quality of the wood bonding depending on the method of applying the selected thermoplastic biopolymers

Gumowska Aneta, Kowaluk Grzegorz

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

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2021

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No. 116

78--85

EN

The quality of the wood bonding depending on the method of applying the selected thermoplastic biopolymers. The aim of the research was to determine the effect of the method of applying the biopolymer on the surface of bonding solid wood elements on the quality of the obtained adhesive connection. The results of conducted mechanical research show that the highest average value of shear strength was observed for birch lamellas bonded with PLA, both with the first and second method of application. In case of estimating the quality of the bonding of wooden elements, better results were achieved for PLA and the second method of application the "green" adhesive.

19

The effect of the surface preparation method on the ultimate strength of a single lap adhesive joints of selected construction materials

Rudawska Anna, Miturska Izabela, Stančekovă Dana

Technologia i Automatyzacja Montażu

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2020

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nr 4

14--20

EN

The aim of the article was to present issues related to the determination of the influence of the surface preparation method on the strength of adhesive joints made of three types of construction materials: structural steel C45, aluminium alloy EN AW-1050A and stainless steel 1.4401. The surfaces of the analysed materials were prepared by machining with three different abrasive tools of different gradations: P120, P220, P400. Adhesive joints were prepared using the E53/Z-1/100:10 epoxy adhesive composition. After the process of adhesive joint curing, destructive tests were carried out on the Zwick/Roell Z150 strength machine, in accordance with PN-EN 1465 standard, which determined the shear strength of the analyzed joints. During the tests it was observed that the most advantageous method of surface preparation is treatment using P220 grit abrasive.

PL

Celem artykułu było zaprezentowanie zagadnień związanych z określeniem wpływu sposobu przygotowania powierzchni na wytrzymałość połączeń klejowych wykonanych z trzech rodzajów materiałów konstrukcyjnych: stali konstrukcyjnej C45, stopu aluminium EN AW-1050A oraz stali nierdzewnej 1.4401. Powierzchnie analizowanych materiałów zostały przygotowane poprzez obróbkę trzema różnymi narzędziami ściernymi różnej gradacji: P120, P220, P400. Połączenia klejowe przygotowano z użyciem kompozycji klejowej epoksydowej E53/Z-1/100:10. Po procesie utwardzania spoiny klejowej przeprowadzono badania niszczące na maszynie wytrzymałościowej Zwick/Roell Z150, zgodnie z normą PN-EN 1465, dzięki którym wyznaczono wytrzymałość na ścinanie analizowanych połączeń. W trakcie badań zaobserwowano, że najkorzystniejszym sposobem przygotowania powierzchni jest obróbka wykorzystująca ścierniwo ziarnistości P220.

20

Effect of temperature on the shear strength of GFRP-aluminium alloy 2024-T3 single lap joint

Kubit Andrzej, Bucior Magdalena, Kluz Rafał

Technologia i Automatyzacja Montażu

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2020

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nr 1

30--35

EN

The paper presents the results of experimental studies determining the effect of temperature on the shear strength of the adhesive joint between the layers of the fiber metal laminate (FML). The tests were carried out for composites being a combination of 2024-T3 aluminum alloy sheet and Glass Fiber-Reinforced Polymer (GFRP) made in the autoclave process. The key factor determining the quality of layered composites is the high strength adhesive joint between the layers. Due to the possibility of extreme temperature conditions during utilization of the composite structure, tests were carried out at reduced temperatures, i.e. -60°C, as well as elevated temperatures, i.e. 80°C. The obtained results were related to the results obtained at a room temperature (RT). The study showed that at the elevated temperature the shear strength increased by approx. 10% compared to the result obtained at room temperature. There is also a significant reduction in the stiffness of the joint as the temperature increases. In turn, a slight increase in joint stiffness was demonstrated for the reduced temperature.

PL

W pracy przedstawiono wyniki badań eksperymentalnych określających wpływ temperatury na wytrzymałość na ścinanie połączenia adhezyjnego pomiędzy warstwami składowymi hybrydowego kompozytu metalowo-włóknistego (FML). Próby przeprowadzono dla kompozytów będących połączeniem blachy ze stopu aluminium 2024-T3 oraz kompozytu szklanego polimerowo-włóknistego (ang. Glass Fiber-Reinforced Polymer - GFRP) wykonanych w procesie autoklawowym. Kluczowym czynnikiem determinującym jakość kompozytów warstwowych jest wysokiej wytrzymałości połączenie adhezyjne pomiędzy warstwami. Ze względu na możliwość występowania różnych warunków temperaturowych w procesie eksploatacyjnym struktury kompozytowej, zrealizowano badania w temperaturach obniżonej tj. -60°C, a także podwyższonej tj. 80°C. Uzyskane rezultaty odniesiono do wyników uzyskanych w temperaturze pokojowej. W pracy wykazano, że w podwyższonej temperaturze dochodzi do wzrostu wytrzymałości na ścinanie o ok. 10% w stosunku do rezultatu uzyskanego w temperaturze pokojowej. Dochodzi tu także do znacznego obniżenia sztywności połączenia wraz ze wzrostem temperatury. Dla obniżonej temperatury wykazano z kolei nieznaczny wzrost sztywności połączenia.