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  1. 28 Materiały Budowlane
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1
Content available remote Właściwości użytkowe ważne w kontekście projektowania murów
Fudalej Piotr, Łaskawiec Katarzyna, Wieczorek Michał
Materiały Budowlane
|
2024
|
nr 4
54--57
2
Content available Municipal waste management based on geomechanical assessments of the landfill site slope - a case study in southern Poland
Janoszek Tomasz, Nguyen Phu Minh Vuong, Grabowski Jacek
Journal of Sustainable Mining
|
2024
|
Vol. 23, iss. 2
185--198
EN
Over time, municipal waste landfills tend to go higher and become larger. The stability of the municipal landfill slope is one of the basic geotechnical tasks. This task ensures continuous waste deposition on the landfill surface and safety in its surroundings. With the increasing height and volume of the landfill, it is difficult to estimate the available area of the municipal landfill, where more waste can be safely deposited due to a number of variable factors, such as the geotechnical conditions of the municipal landfill, the morphological composition, age, and degree of compaction and decomposition of the deposited waste. This paper presents an attempt to determine the available area of a landfill where municipal waste can be safely deposited for further operation. For this purpose, a numerical slope stability analysis was carried out using the finite difference method code FLAC3D, presenting the actual geomechanical conditions of a landfill located in southern Poland. Based on the numerical results, options for municipal waste storage were presented and discussed. The proposed design chart aims to help landfill owners/managers make an adequate decision in terms of landfill planning and design.
3
Content available remote Wpływ zróżnicowanego składu kompozytu geopolimerowego na adhezję z kompozytem asfaltowym
Granatyr Krzysztof, Bołtryk Michał, Kalinowska-Wichrowska Katarzyna, Szeligowski Paweł
Materiały Budowlane
|
2023
|
nr 5
5--9
PL
W artykule przedstawiono badania wpływu zróżnicowanego składu kompozytu geopolimerowego na adhezję z kompozytem asfaltowym. Zmiennymi w planie eksperymentu były zawartość zaprawy geopolimerowej, stężenie molowe NaOH oraz grubość warstwy ochronnej kompozytu geopolimerowego. Przyjęto stałe warunki dojrzewania. Otrzymane wyniki wskazują na bardzo dobre właściwości kompozytu zespolonego niezależnie od badanych czynników.
EN
The article presents the research on the influence of the variable composition of the geopolymer composite on the adhesion with the asphalt composite. The variables in the experiment plan were the content of the geopolymer mortar, the molar concentration of NaOH and the thickness of the protective layer made of the geopolymer composite. Constant maturation conditions were assumed. The obtained results indicate very good properties of the composite regardless of the tested variable.
4
Content available Shear strength characteristics of weathered jointed Kenny Hill interbedded formation for cylindrical specimen under direct shear test
Abbas Hasan Ali, Mohamed Zainab, Taher Muntadher J., Kudus Sakhiah Abdul, Salman Manaf Raid, Ghaltan Hasanain Muhammad
International Journal of Applied Mechanics and Engineering
|
2023
|
Vol. 28, no. 2
1--12
EN
The sliding failures commonly occur in interbedded formations along the weakness plane of the bedding plane a sedimentary rock or the joint interface. Therefore, studying the shear strength characteristics at the bedding plane or interface is crucial for evaluating the expected failure plane. In this study, the shear strength characteristics of planar jointed Kenny Hill shale, sandstone, and shale-sandstone specimens were investigated using the direct shear box method. The results reveal that the friction angle values for the planar sandstone, shale-sandstone, and shale are 31.28°, 21.1°, and 19.34°, respectively. These findings, combined with the shear stress-strain behavior, suggest that the interface (shale-sandstone) is primarily influenced by the shale characteristics rather than the sandstone characteristics. Hence, it is important to consider failure along the interface when analyzing critical conditions, particularly in slope failure scenarios.
5
Content available Laboratory tests of solid and hollow concrete beams made with glass waste
Alharishawi Salam Salman Chiad, Rajaa Nagham, Jabur Aqeel Raheem
Archives of Civil Engineering
|
2023
|
Vol. 69, nr 4
5--20
EN
The application of used glazed waste in concrete production can improve the performance of the structure of the building. Flexural and shear behavior and action of reinforced Hollow Glass Concrete Beams (HGCB) and Solid Glass Concrete Beams (SGCB) made with glass waste under a two-point load are studied in this paper. In this work, 6 reinforced concrete solid and hollow beams were tested under a four-point bending test to evaluate and calculate the flexural behavior of SGCB and HGCB. For that purpose, Beams were prepared with 1000 mm length, 230 mm height, and 120 mm. All beams were divided into groups and named according to the space stirrups steel bar. The experimental work investigates five main variables which are: first: the comparison between SGCB and HGCB with the concrete beams made with glass waste (Glass Concrete Beam GCB), second: comparison between Solid Concrete Beams for Normal Concrete Beams (NCB), and GCB, three: comparison between Hollow Concrete Beams for NCB and GCB, four: the comparison between HGCB and HCB, last: the comparison between SGCB and SCB. The test results indicated that GCB was offered higher strength than NCB, but the load-slip behavior of all specimens is similar for both types of concretes, and the bond strength is not influenced by steel specimens. Furthermore, the results of this study indicated that the contribution of GCB to the load is indicated to be considerable. The results indicate that the hollow opening affected the ultimate load capacity and deflection of HGCB.
6
Content available remote Cyclic response and shear mechanisms of RC short walls strengthened with engineered cementitious composites thin layers
Zhang Yangxi, Zhang Shijun, Li Tong, Deng Mingke
Archives of Civil and Mechanical Engineering
|
2023
|
Vol. 23, no. 3
art. no. e148, 2023
EN
This paper investigates the effectiveness of engineering cementitious composites (ECC) thin layers for seismic strengthening of reinforced concrete (RC) short walls with high axial load ratios. Three RC short walls with an aspect ratio of 1.1 were tested under cyclic loading: one control wall and two ECC strengthened walls, adopting two different strengthening layer schemes. The results showed that the failure mode, damage tolerance, lateral stiffness, shear strength, and energy dissipation of the strengthened walls were improved to certain extents. The mesh grid ECC layer was proved an effective and applicable technique, the shear strength and energy dissipation of the corresponding strengthened wall were improved by 37.2% and 33.5%, respectively, and the addition of mesh grid and tie bars in the ECC layer prevented the debonding failure at the ECC/concrete interface. Besides, the shear resistance mechanisms of the test specimens were idealized by the strut-and-tie model, the contribution of cracked ECC tensile strength to shear was considered in the horizontal and vertical mechanisms. The predicted shear strengths of the RC walls agreed well with the test values.
7
Content available The influence of the manufacturing method on the mechanical properties of the honeycomb core sandwich composite
Janiszewski Jacek, Przybyłek Paweł, Bieńczak Rafał, Komorek Łukasz, Schwarzenberg Miłosz
Technologia i Automatyzacja Montażu
|
2022
|
nr 4
20--33
EN
Reducing weight and fuel consumption is one of the main goals of modern aeronautical engineering. The most common materials to achieve this goal are composite layered materials, including the sandwich ones. High strength, stiffness and low density have made sandwich composites one of the fundamental materials of the aerospace industry. Sandwich-structured composites can be manufactured with a variety of methods, differing primarily in the manufacturing time, which translates into an overall cost of making a composite component. The research focused on three methods of manufacturing sandwich composite materials with a honeycomb core, differing in the number of operations, during which it was possible to obtain a finished composite panel (single-phase, two-phase and three-phase methods). The authors manufactured and examined composites with a honeycomb cover and two composite glass fibre-reinforced covers. The composites were made by means of the vacuum bag method. As a result of the conducted study, it was found that composites manufactured with the single-phase method have the shortest manufacture time as well as the lowest material consumption, however their strength properties are the lowest. The two-phase method requires a longer manufacture time and more material consumption, however it makes it possible to obtain a composite with higher strength compared with the single-phase method. The three-phase method has the longest composite manufacture time and the highest material consumption.
PL
Zmniejszenie masy i zużycia paliwa jest jednym z głównych celów współczesnej inżynierii lotniczej. Najpopularniejsze materiały, które pozwalają osiągnąć ten cel, to materiały kompozytowe warstwowe w tym przekładkowe. Wysoka wytrzymałość, sztywność i niska gęstość, sprawiły, że kompozyty przekładkowe stały się jednym z podstawowych materiałów przemysłu lotniczego. Kompozyty przekładkowe z wypełniaczem strukturalnym mogą być wytwarzane różnymi metodami, różniącymi się przede wszystkim czasem wytwarzania, co przekłada się na ogólny koszt wykonania elementu kompozytowego. W badaniach przeanalizowano trzy metody wytwarzania materiałów kompozytowych przekładkowych w wypełniaczem ulowym różniące się liczbą operacji podczas których uzyskano gotową płytę kompozytową (metoda jednofazowa, dwufazowa i trójfazowa). Wytworzono i badano kompozyty zbudowane z rdzenia ulowego oraz dwóch kompozytowych okładek wzmacnianych włóknami szklanymi. Kompozyty wykonano metodą worka próżniowego. W efekcie przeprowadzonych badań stwierdzono, że kompozyty wytworzone metodą jednofazową cechują się najkrótszym czasem produkcji jak i najmniejszym zużyciem materiałów, ale ich właściwości wytrzymałościowe są najniższe. Dwufazowa metoda wymaga dłuższego czasu produkcji i większego zużycia materiałów, natomiast pozwala uzyskać kompozyt o większej wytrzymałości w porównaniu do metody jednofazowej. Trójfazowa metoda cechuje się najdłuższym czasem wykonania kompozytu i największym zużyciem materiałów.
8
Content available Effect of overlap length on the strength of adhesive joints of steel sheets
Doluk Elżbieta, Rudawska Anna, Miturska-Barańska Izabela, Ogrodniczek Jacek
Technologia i Automatyzacja Montażu
|
2022
|
nr 4
3--6
EN
The study evaluates the shear strength of the single-lap adhesive joints made of C45 carbon steel. The influence of the overlap length on the shear strength of the adhesive joint was tested. The elongation of the samples was also tested. Before the bonding process, the samples were treated with P180 abrasive paper and degreased. The adhesive joints were made using the Epidian 53/Z1/100:10 adhesive composition. The strength tests were carried out on a Zwick/Roell Z150 testing machine. The maximum value of the shear strength was obtained for the lap Lz1 = 13 mm and the minimum for Lz4 = 19 mm.
PL
W pracy dokonano oceny wpływu długości zakładki na wytrzymałość na ścinanie jednozakładkowych połączeń klejonych wykonanych ze stali węglowej C45. Podczas eksperymentu zbadano także wydłużenie próbek. Przed rozpoczęciem procesu klejenia próbki zostały obrobione papierem ściernym P180 i odtłuszczone. Połączenia klejowe wykonano przy użyciu kompozycji klejowej Epidian 53/Z1/100:10. Badania wytrzymałościowe przeprowadzono na maszynie wytrzymałościowej Zwick/Roell Z150. Maksymalną wartość wytrzymałości na ścinanie uzyskano dla długości zakładki Lz1 = 13 mm, a minimalną dla Lz4 = 19 mm.
9
Content available remote Analiza pracy poprzecznej łączników prętów jako przykład działań B+R w nowoczesnej prefabrykacji betonowej
Surma Mateusz, Wojciechowski Szymon
Materiały Budowlane
|
2022
|
nr 3
28--29
10
Content available 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
|
2022
|
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).
11
Content available Shear capacity of the interface between concretes cast at different time in the light of experimental investigations and codes of practice
Gołdyn Michał
Archives of Civil Engineering
|
2022
|
Vol. 68, nr 1
275--298
EN
The paper presents selected issues related to the load carrying capacity of joints between concretes cast at different times. The most important factors affecting the shear resistance, such as: surface roughness (profile), shear reinforcement ratio, concrete strength as well as the aggregate composition are discussed, including results of previous experimental studies conducted on push-off specimens and composite reinforced concrete beams. The differences in behaviour and shear resistance of contacts between ordinary concretes, lightweight aggregate concretes and recycled aggregate concretes are presented. Principles of interface design in the light of codes of practise: AASHTO-LRFD, ACI 318-19, EN 1992-1-1 and prEN 1992-1-1 were described. The theoretical predictions were compared with 184 results of experimental tests on push-off specimens. It has been found that most of the procedures allow for a safe estimation of the load carrying capacity of interfaces - with and without shear reinforcement. However, the obtained results were mostly conservative (depending on the considered design procedure, ratio of the experimental to theoretical load carrying capacity lies in range 1.51÷2.68). This may indicate that the description of shear transfer mechanism between concretes cast at different times is still imperfect and need to be improved.
PL
W artykule przedstawiono wybrane zagadnienia związane z nośnością styków pomiędzy betonami układanymi w różnym czasie. Konieczność zapewnienia właściwego zespolenia pomiędzy “starym” i “nowym” betonem zachodzi nie tylko w przypadku konstrukcji nowo wznoszonych, w których stosuje się elementy prefabrykowane, lecz także w obiektach już istniejących, gdy zachodzi potrzeba wzmocnienia konstrukcji. Tematyka nośności styków pomiędzy betonami układanymi w różnym czasie stanowi przedmiot badań eksperymentalnych prowadzonych od lat 60. ubiegłego wieku. Za pierwszy model opisujący zachowanie styków uznaje się teorię shear-friction, przedstawioną przez Masta i opisaną szczegółowo przez Birkelanda i Birkelanda. Model ten stosowany jest do dnia dzisiejszego w procedurach obliczeniowych ACI 318 i AASHTO-LRFD, jednak badania eksperymentalne prowadzone na przestrzeni lat wykazały potrzebę rewizji przyjętych założeń, polegających m.in. na uwzględnieniu sił adhezji czy kompozycji stosu okruchowego.
12
Content available 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
|
2022
|
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.
13
Content available remote 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
|
2022
|
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.
14
Content available remote Shear behavior and design of an innovative embedded connector with flange for steel–concrete composite girder
Zhang Zhe, Zhang Sheng-Nan, Deng En-Feng, Yu Chen-Yang, Tang Yi, Wang Yan, Sun Dong-Sheng
Archives of Civil and Mechanical Engineering
|
2022
|
Vol. 22, no. 4
art. no. e195, 2022
EN
Connectors are crucial for steel–concrete composite girder to insure cooperative work of the two different materials. Flanges in connectors can be used as supports and templates to accelerate construction progress. Embedded connector is a type of connector formed by embedded web with opening holes for arranging reinforcements. However, traditional embedded connector does not include flanges. In this paper, an embedded connector with flanges was proposed. Three full-scale specimens were fabricated and push-out tests were conducted to investigate the shear behavior of the innovative connector. The failure mode and shear performance of the traditional embedded shear connector without flanges and the innovative connector with flanges were compared. Three-dimensional finite-element model (FEM) was developed and validated based on the test results. Furthermore, parametric analysis was conducted to further study the effects of the strength of the concrete, diameter of the hole, diameter of the perforating rebar, embedding depth, and height of the corrugated web on the shear performance of the innovative connector. The results of the parametric study were analyzed to evaluate the shear capacity for the embedded connector with flanges. Finally, an analytical model was proposed to predict the shear strength of the innovative embedded connector, which will provide important guidance for engineering application.
15
Content available remote Nonlinear finite element analysis and parametric study of executable RCS connections
Doost Rooholah Bakhtiari, Sadraie Hamid, Khaloo Alireza, Badarloo Baitollah
Archives of Civil and Mechanical Engineering
|
2022
|
Vol. 22, no. 4
art. no. e204, 2022
EN
This paper compares the results of a nonlinear finite element analysis (FEA) of an internal hybrid steel beam to RC column connections with those of the experiment on a half-scale. This study used extended face bearing plates (EFBP) embedded in the panel zone (PZ) to make prefabricated RC column to steel beam connections (PRCS). Steel beam flanges were made to be stronger than scaled sections to transfer more force to the PZ. Nonlinear FEA was performed with ABAQUS software to evaluate the connections under unidirectional loading. Failure mode, connection stiffness, and PZ shear strength determined by nonlinear FEA matched well with the experimental findings. PRCS1 model was used to evaluate the number of PZ stirrups, axial load on the column, width and height of EFBP, and height of stiffener connected to the beam flange. PZ shear strength and stiffness were significantly improved by increasing EFBP width. Increasing the height of EFBP only with increasing the height of the stiffener can increase the shear strength of the PZ. Increasing the axial load of the column had a significant effect on increasing the shear strength of the PZ. PZ shear strength of the PRCS4 with cover plates (CP) was also assessed by developing its numerical model and strengthening the beams and columns. The presence of CP in the sample without a steel web panel (SWP) illustrated a significant effect compared to the sample with SWP. Based on the performance of the CP in different PZ forms, the formulation was developed to determine the shear strength of CP.
16
Content available 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
|
2022
|
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.
17
Content available remote 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
|
2022
|
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.
18
Content available Effects of hydrocarbon contamination on the engineering geological properties of Neogene clays and Pleistocene glacial tills from Central Poland
Dobak Paweł, Izdebska-Mucha Dorota, Stajszczak Piotr, Wójcik Emilia, Kiełbasiński Kamil, Gawriuczenkow Ireneusz, Szczepański Tomasz, Zawrzykraj Piotr, Bąkowska Anna
Acta Geologica Polonica
|
2022
|
Vol. 72, no. 4
529--555
EN
Petroleum products influence the engineering behaviour of the soil. Neogene clays and glacial tills from Central Poland were tested under laboratory conditions to evaluate the changes of selected physical and mechanical parameters: particle size distribution, particle density, swelling, shear strength and permeability. Four petroleum products were used in the experiments: diesel fuel, kerosene, jet fuel and mineral engine oil. The study revealed that even for the lowest degree of contamination the values of physical and mechanical properties of the soils changed significantly. Greater variation can be expected in soils contaminated with high-viscosity compounds. Also, higher relative changes were found for glacial tills than for Neogene clays. Consolidation tests revealed changes in soil permeability depending on the soil composition and the physical properties of the contaminant – considerable reduction of permeability was observed for glacial tills contaminated with light Jet fuel, while the reduction was lower for Neogene clays. The obtained results indicate the role of mesopores and the dimensionless pore pressure coefficient in changes of soil permeability. The methodological issues regarding testing and analysing the hydrocarbon-contaminated soils were also presented and discussed, which might be useful for researchers studying contaminated soils.
19
Content available remote 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.
20
Content available remote 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.
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