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1

Procedura i badania weryfikacyjne wyznaczania wytrzymałości na ścinanie połączeń ścian murowanych

Galman Iwona, Jasiński Radosław

Materiały Budowlane

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2026

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nr 1

91--92

2

Relationships between Shear Strength Parameters with Mineralogy and Index Properties of Compacted, Unsaturated Soils

Fondjo Armand Augustin, Vanapalli Sai K., Ray Richard P., Theron Elizabeth

Studia Geotechnica et Mechanica

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2025

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Vol. 47, nr 1

65--88

EN

The objective of this study is to assess the influences of soil index properties, swelling parameters, and soil mineralogy on unsaturated shear strength parameters (ϕ‘, ϕb, c‘) of compacted expansive soils. The laboratory tests include the grain size distribution, specific gravity (Gs), Atterberg limits, swelling potential, X-ray diffraction, modified Proctor compaction, soil suction, and triaxial testing. MINITAB 19 statistical analysis software generates the tri-dimensional surface graphs. The values ϕ‘, ϕb, and c‘ are majorly influenced by water (%), Gs, and clay (%). ϕ‘ shows a strong correlation with free swell ratio (FSR), free swell index (FSI), and void ratio. ϕb demonstrates a strong relationship with liquid limit, plasticity index, and γd (dry unit weight). ϕ‘ and c‘ portray a moderate relationship with liquid limit, plasticity limit, and γd. ϕ‘ exhibits a moderate correlation with smectite (%) and plagioclase (%). ϕb describes a strong relationship with smectite (%) and a moderate correlation with plagioclase and K-feldspar (%). c‘ depicts a moderate correlation with smectite (%), K-feldspar (%), and plagioclase (%). The matric suction controls the behaviour of unsaturated soils. Nonetheless, the influences of soil index properties, swelling potential, and mineralogy on shear strength are not marginal. These findings provide a good insight into the behaviour of unsaturated expansive soils and contribute to enhancing geotechnical modelling.

3

Stanowisko badawcze do wyznaczania wytrzymałości na ścinanie połączeń ścian murowanych

Galman Iwona, Jasiński Radosław

Materiały Budowlane

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2025

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nr 2

63--64

4

Kształtowanie murowych ścian usztywniających uproszczonymi metodami normowymi

Jasiński Radosław, Grzyb Krzysztof

Inżynieria i Budownictwo

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2025

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R. 81, nr 4

380--385

PL

Problem kształtowania ścian usztywniających w budynkach murowanych traktowany jest w sposób bardzo lakoniczny w aktualnych normach. Zaleca się stosowanie symetrycznego układu ścian oraz dotrzymanie minimalnej grubości. Zróżnicowana sztywność ścian spowodowana obecnością otworów nawet w symetrycznym układzie ścian powoduje, że rozdział obciążeń wymaga zastosowania autorskich procedur obliczeniowych lub MES. Do dyspozycji projektantów konstrukcji pozostają metody uproszczone zamieszczone w Eurokodzie 6-3, które w prosty sposób pozwalają sprawdzić warunki ULS ścian usztywniających. W publikacji przedstawiono autorskie metody sprawdzania warunków ULS oraz SLS ścian usztywniających zgodnych z zapisami Eurokodu 6 oraz polskich tradycji w tym zakresie.

EN

The problem of shaping stiffening walls in masonry buildings is treated in a very laconic way in current standards. It is recommended to use a symmetrical arrangement of walls and to maintain a minimum thickness. The varied stiffness of walls caused by the presence of openings even in a symmetrical arrangement of walls means that the distribution of loads requires the use of proprietary calculation procedures or FEM. The simplified methods included in Eurocode 6-3 are available to structural designers, which allow for a simple verification of the ULS conditions of stiffening walls. The publication presents orginal methods for checking the ULS and SLS conditions of stiffening walls in accordance with the provisions of Eurocode 6 and Polish traditions in this area.

5

Shear Strength of Organic Soils Modified by Mineral Materials

Brzeziński Bartłomiej, Olchawa Andrzej

Rocznik Ochrona Środowiska

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2024

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Tom 26

168--177

EN

The paper presents the test results of the shear strength of composite materials, in which the base material was peat. The materials modifying the mineral part of the peat ground skeleton were fly ash and hydrated lime. The research was carried out for two groups. In group 1, the ratio of the mass of the peat skeleton to the mass of fly ash was equal to one, and in group 2, it was two. Hydrated lime content in the unit mass of the composite in group 1 was 2.4, 4.8 and 9.2%. In the second group, it was 1.6, 3.2 and 6.4%. The test results showed that the materials from group 1. (P/FA = 1) are characterised by the highest shear strength compared to materials from group 2. (P/FA = 2), regardless of the content of hydrated lime. It should also be noted that the shear strength of the materials of group 1 was significantly higher than the shear strength of the base material, which was peat.

6

Properties of a Sand and Bentonite Mixture as a Material for Spot Seals of Low Flood Embankments in the Area of Żuławy Elbląskie

Brzeziński Bartłomiej, Czyżykowski Szymon, Olchawa Andrzej, Wierzbicka Marianna

Rocznik Ochrona Środowiska

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2024

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Tom 26

383--392

EN

The paper presents the test results of a bentonite and sand mixture as a mineral material used for spot seals of low flood embankments in the area of Żuławy Elbląskie. The test results showed very good properties of the mixture, i.e., good compaction, a low filtration coefficient, and significantly higher shear strength compared to the construction material of the flood embankment in Nowe Dolne. The obtained water permeability values of 10-8 m/s are characteristic of very low permeable soils. The strength parameters of the mixture are φ = 34.8o and cohesion c = 72.69 kPa. It should also be noted that the shear strength of the B/Sa mixture is significantly higher compared to the shear strength of the construction material of the flood embankment in Nowe Dolno.

7

Właściwości użytkowe ważne w kontekście projektowania murów

Fudalej Piotr, Łaskawiec Katarzyna, Wieczorek Michał

Materiały Budowlane

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2024

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nr 4

54--57

8

Badania na ścinanie belek zbrojonych podłużnie i poprzecznie prętami FRP

Szczech Damian, Kotynia Renata

Materiały Budowlane

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2024

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nr 4

32--36

PL

W artykule przedstawiono przegląd literatury w dziedzinie badania na ścinanie belek zbrojonych podłużnie i poprzecznie prętami FRP. Przegląd badań obejmuje zestawienie parametrów różnych zmiennych: rodzaju zastosowanego zbrojenia; wysokości użytecznej elementu; szerokości belek; smukłości ścinania; wytrzymałości betonu na ściskanie; stopnia zbrojenia podłużnego i poprzecznego; modułu sprężystości prętów; kształtu strzemion; porównania z elementami zbrojonymi prętami stalowymi, a także schematu statycznego. Na podstawie przeglądu wiedzy zaproponowano program badań własnych.

EN

This article presents a review of research in the field of shear tests of beams with longitudinal and transverse FRP reinforcement. The research review includes a summary of the parameters of various variables: type of reinforcement, depth of the element, width of the beams, shear span to depth ratio, compressive strength of concrete, longitudinal and transverse reinforcement ratio, modulus of elasticity of bars, shape of stirrups, comparison with elements reinforced with steel bars, as well as the static scheme. Based on the foreign studies the own research program has been proposed.

9

Analysis of the effect of variable parameters on the shear capacity of elements reinforced with FRP bars

Szczech Damian, Kotynia Renata

Materiały Budowlane

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2024

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nr 11

10--19

EN

This paper presents an analysis of variable parameters on the shear capacity of elements reinforced with FRP bars: longitudinal reinforcement ratio; transverse reinforcement ratio; axial stiffness of reinforcement; shear slenderness; concrete compressive strength; spacing of stirrups; depth; shape of beam cross-section; inclination of transverse reinforcement and bond behaviour of stirrups.

PL

W artykule przedstawiono analizę parametrów zmiennych na nośność na ścinanie elementów zbrojonych prętami FRP: stopnia zbrojenia podłużnego; stopnia zbrojenia poprzecznego; sztywności osiowej zbrojenia; smukłości ścinania; wytrzymałości betonu na ściskanie; rozstawu strzemion; wysokości użytecznej; kształtu przekroju poprzecznego belki; nachylenia zbrojenia poprzecznego oraz przyczepności strzemion.

10

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

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2024

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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.

11

Numerical Assessment of CFS-SWP with Different Door Opening Positions

Rouaz Idriss, Rafa Sid Ali, Ghribi Zakaria

Inżynieria Mineralna

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2024

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Vol. 1, no. 2

art. no. 21

EN

A prevalent method of countering lateral forces in seismic regions for structures made of Cold Formed Steel (CFS) involves employing Shear Walls Panels (SWP) covered with steel sheets. The overall reaction and various failure modes during lateral loading have become apparent, continuing to capture the interest of designers and researchers. Typically, door openings are everpresent in the front and rear elevations where SWPs find their optimal position to ensure lateral stability in CFS structures. These architectural design features translate into reduced areas for lateral load resistance throughout the structure. Through numerical simulations, this paper discusses the effect of the door opening, with different positions in the SWP, on the shear strength performance of CFS-SWP. A Finite Element (FE) modelling is developed using the ABAQUS software, taking into account material and geometrical nonlinearities, as well as assembled sheathing-to-framing connections. In order to validate the FE modelling with available experimental data, comprehensive static nonlinear analyses are conducted on CFS-SWP under monotonic load. A good agreement is achieved, namely: nonlinear strength-displacement response, ultimate shear strength, and failure modes. The effect of the door positions is assessed, in which, the opening position is found to have a significant impact on the CFS-SWP performance. The results reveal that the position of the door opening between the central and the edge of the SWP produces better performance than the other positions. However, the position of the door at the edge of the SWP induces additional failure modes in the vicinity of the chord studs.

12

Dimensional stability and mechanical performance of face-glued spruce-pine-fir and Douglas-fir studs

Cook Sophia, Ghavidel Amir, Zhou Jianhui

Drewno : prace naukowe, doniesienia, komunikaty

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2024

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Vol. 67, nr 214

Art. no. 193420

EN

Warpage of dimensional lumber has been identified as the major issue for its use in wood construc tion prefabrication in North America. Face-gluing is a promising technique to mitigate warping of dimensional lumber. This paper studies the dimensional stability and mechanical performance of 2-ply face-glued lumber as a means of reducing warpage in both spruce-pine-fir (S-P-F) and Douglas-fir (D. fir) lumber. Planks were paired and subsequently laminated based on their initial dynamic modulus of elasticity (MOE) and shape compatibility. Warp was measured in twist, bow, and crook at varying moisture contents. Mechanical performance was measured in terms of the MOE, modulus of rupture (MOR), and shear strength. This pairing regime between component planks offers a means to reduce the twist and bow tendencies of face-glued lumber while increasing the unifor mity of lumber strength. Flexural MOE and MOR performances were consistent with visual grades No.1/No.2, showing the potential of face-glued lumber as a value-added product for the automatic prefabrication of wood constructions.

13

Shear strength estimation of a FRP-strengthened RC beam: A comparison between an artificial neural network and guideline equations

Nezaminia Hamid

Computer Methods in Materials Science

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2024

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Vol. 24, No. 3

5--32

EN

In recent years, several experimental tests have been conducted on the shear strengthening of reinforced concrete (RC) beams strengthened by fiber-reinforced polymer (FRP) systems. In this regard, some equations have also been proposed to estimate the shear strength of beams reinforced with FRP systems. The aim of this study is to investigate the estimation of the shear strength of beams reinforced with FRP systems using an artificial neural network model. For this purpose, a comprehensive and extensive review of forty published articles has been carried out to compile data on 304 RC beams strengthened with externally bonded FRP systems to improve their shear strength. These laboratory results have been used to provide a database for the ANN model to evaluate the shear behavior. The input to the ANN model consists of the 11 variables, including the sectional geometry, reinforcement ratio, FRP ratio, and the characteristics of concrete, steel reinforcement, and composite material, while the output variable is the shear strength of the FRP-strengthened RC beam. In order to evaluate the effectiveness of the neural network model in estimating the shear capacity of RC beams, the results obtained from the neural network model are compared with the equations from the Publication No. 345 and ACI 440.2R guidelines. The comparison of the results shows that the predictive power of the proposed model is much better than the experimental guidelines. Specifically, the mean absolute relative error (MARE) criteria for the studied data is 13%, 34% and 39% for the ANN model, ACI 440.2R guideline and the Publication No. 345 guideline, respectively.

14

Impact loading of tendon reinforcement systems used for ground control: a critical literature review

Mottahedi Adel, Aziz Naj, Remennikov Alex, Mirzaghorbanali Ali, Marston Kevin

Archives of Mining Sciences

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2024

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Vol. 69, no. 4

711--743

EN

The present paper reports on various test methods and techniques which have been developed throughout the last decades. These methods have been used to evaluate both axial and shear performance of tendons under impact loading mode. Based on the literature review conducted on the scientific documents, published between 1992 and 2024, the developed facilities mainly work based on the direct impact and momentum transfer methods. In the direct impact method, which can be done in-situ and in the laboratory, the impact energy is applied by a mass freely falls to the test sample. In the momentum transfer method, the test assembly, consisting of both the mass and test sample free-fall at the beginning of the test until the movement of the assembly is halted by a stopper, and the momentum of the mass is transferred to the test sample. Besides, most of the current facilities are working based on the direct impact method. It was also found that less research have been conducted on dynamic shear testing, especially high-strength cable bolts, as most of the facilities have been designed for pull testing. In addition, it was found that in dynamic pull-out tests of rock bolts, two main mechanisms of energy absorption are identified: steel plastic deformation and bolt sliding within the encapsulation medium. The first impact plays a key role in energy absorption, causing significant permanent displacements, while the energy consumed in displacing the bolt is more indicative of dynamic behavior than the total input energy. According to the results, the tendons that undergo static deformations before dynamic loading are more prone to failure as some parts of their performance have already lost. Meanwhile, differences between dynamic and static shear tests suggest that dynamic tests require less energy for failure, as friction is ineffective in impact loading. Finally, the study highlights gaps in the current understanding of tendon performance under impact loading, with potential research directions aimed at improving safety in underground excavation.

15

Effect of shear rate and saturation on shear strength of mineral and anthropogenic soil

Gruchot Andrzej, Zydroń Tymoteusz

Archives of Civil Engineering

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2024

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Vol. 70, nr 2

97--117

EN

The aim of the study was to determine the shear strength of mineral and anthropogenic soil of similar grain size as a function of the applied shear rate and water saturation. Stability calculations using the finite element method of the road embankment model were also carried out to demonstrate the variation in factor of safety values depending on the adopted values of the angle of internal friction and cohesion. The tests were carried out in a direct shear apparatus in a 100 x 100 mm box with a sample height of 20.5 mm. The samples were formed directly in the apparatus box at optimum moisture content until a compaction index of IS = 1.00 was obtained. Tests were carried out under conditions without and with water saturation at shear rates of 0.01, 0.05, 0.1, 0.5 and 1.0 mm·min-1 until 18% horizontal displacement was achieved. The results showed that the effect of shear rate on the strength parameters was not unequivocal and was much smaller than the changes caused by saturation of samples. An increase in shear rate resulted in small changes in the angle of internal friction with a tendency towards a decrease. In contrast, cohesion varied over a much larger range with increasing shear rate, with an apparent initial decrease and subsequent increase. The saturation of the samples resulted in a decrease in the angle of internal friction of the cohesive soil and an increase for the ash-slag mixture. The cohesion of both soils decreased. The results obtained from the road embankment model stability calculations confirmed that soil saturation had a greater influence on the factor of safety values obtained than the shear rate.

PL

Celem pracy było określenie wytrzymałości na ścinanie gruntu mineralnego i antropogenicznego w zależności od zastosowanych prędkości ścięcia i zawodnienia. Wykonano również obliczenia stateczności metodą elementów skończonych modelu nasypu drogowego w celu wykazania zmian w wartościach współczynnika stateczności w zależności od przyjętych wartości kąta tarcia wewnętrznego i spójności. Badania przeprowadzono w aparacie bezpośredniego ścinania w skrzynce o wymiarach 100 × 100 mm i wysokości próbki 20,5 mm. Próbki formowano bezpośrednio w skrzynce aparatu przy wilgotności optymalnej do uzyskania wskaźnika zagęszczenia IS = 1,00. Badania przeprowadzono w warunkach bez i z zawodnieniem przy prędkości ścięcia 0,01, 0,05, 0,1, 0,5 i 1,0 mm·min-1. Wyniki badań wykazały, że wpływ prędkości ścięcia na parametry wytrzymałości nie był jednoznaczny i był znacznie mniejszy niż zmiany spowodowane zawodnieniem próbek. Wzrost prędkości spowodował niewielkie zmiany kąta tarcia wewnętrznego z tendencją na jego zmniejszenie. Natomiast spójność wraz ze wzrostem prędkości ścięcia wahała się w znacznie większym zakresie, z widocznym początkowym jej zmniejszeniem, a następnie zwiększeniem. Uzyskane wyniki obliczeń stateczności modelu nasypu drogowego potwierdziły, że większy wpływ na uzyskiwane wartości współczynnika stateczności miało zawodnienie gruntu niż prędkość ścięcia.

16

Effect of polypropylene fibres on the shear strength of fine-grained soil

Zydroń Tymoteusz, Gruchot Andrzej, Zawiła Dominika

Archives of Civil Engineering

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2024

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Vol. 70, nr 3

325--341

EN

This paper presents the results of shear strength tests of fine-grained soil reinforced by randomly oriented fibres. The tests were carried out in a direct shear apparatus on samples with a diameter of 100 mm and a height of 20 mm. The samples were formed directly in the apparatus box at a natural moisture content and two values of the degree of compaction (IS = 0:79 and 0.90). The studies were carried out for samples of natural moisture content and for soaked ones. The two types of polypropylene fibres were used: monofilament and fibrillated (of traded names Fibermesh 300-e3 and SikaCem Fiber-12, respectively). The fibre content was 0.25; 0.50 and 1.00% by the weight of the dry soil. The results showed that the presence of fibre within the soil increased its the shear strength. The improvement of the shear strength was related to the type of reinforcement, its content and the soil parameters. The maximum increase in shear strength was 47% compared to the shear strength of the unreinforced soil. The increase in shear strength values were related mainly to the increase in the angle of internal friction of the soil. It was found that as the degree of compaction of the soil increases, the higher enhance of the shear strength of reinforced soil occurs. It was also found that the improvement of shear strength of reinforced soaked samples was more significant than for un-soaked ones.

PL

W pracy przedstawiono wyniki badań wytrzymałości na gruntu drobnoziarnistego z dodatkiem zbrojenia rozproszonego. Oznaczenie parametrów wytrzymałości na ścinanie przeprowadzono w aparacie bezpośredniego ścinania na próbkach o średnicy 100 mm i wysokości 20 mm. Próbki były formowane bezpośrednio w skrzynce aparatu przy wilgotności naturalnej, zbliżonej do optymalnej, oraz dwóch wartościach wskaźnika zagęszczenia (IS = 0,79 i 0,90). Próbki konsolidowano przez 60 min przy naprężeniu normalnym 25, 50, 75, 100, 125 kPa, a następnie ścinano z prędkością 0,10 mm·min-1 do momentu uzyskania 18% względnego odkształcenia. Badania przeprowadzono dla zawodnionych niezawodnieniem próbek gruntu. Zbrojenie rozproszone stanowiły dwa rodzaje włókien polipropylenowych (monofilamentowe i fibrylowane o nazwach handlowych odpowiednio Fibermesh 300-e3 oraz SicaCem Fiber-12), które dodawano w ilości 0,25; 0,50 i 1,00% w stosunku do masy szkieletu gruntu. Wyniki badań wykazały, że zastosowanie zbrojenia rozproszonego wpływa pozytywnie na wytrzymałość na ścinanie gruntu, przy czym wpływ ten jest zależny od rodzaju zbrojenia, jego dodatku, a także parametrów geotechnicznych gruntu. Maksymalny wzrost wytrzymałości na ścinanie gruntu ze zbrojeniem wyniósł 47% w stosunku do wartości wytrzymałości na ścinanie gruntu bez dodatku zbrojenia. Stwierdzono, że dodatek zbrojenia wpłynął zasadniczo na wartości kąta tarcia wewnętrznego, a w przypadku spójności był niejednoznaczny. Wyniki badań wykazany również, że włókna monofilamentowe mają bardziej korzystny wpływ na wzmocnienie gruntu niż włókna fibrylowane. Wykazano również, że wpływ zbrojenia na wzmocnienie gruntu jest bardziej efektywny przy wyższym wskaźniku zagęszczenia gruntu, a większy przyrost wytrzymałości na ścinanie gruntu uzyskano w przypadku badań próbek zawodnionych.

17

Shear strengthening of damaged reinforced concrete beams with iron-based shape memory alloy (Fe-SMA) strips: numerical and parametric analysis

Tabrizikahou Alireza, Białasik Jan, Borysiak Sławomir, Fabisiak Mateusz, Łasecka-Plura Magdalena, Jesionowski Teofil, Kuczma Mieczysław

Archives of Civil and Mechanical Engineering

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2024

|

Vol. 24, no. 3

art. no. e189, 2024

EN

Shape memory alloys (SMAs) are metallic materials that are characterized by their ability to restore their original shape after large deformation when activated by heating. This unique property renders SMAs appealing for various civil engineering applications. Iron-based SMAs (Fe-SMAs), including alloys like Fe–Mn–Si, stand out due to their cost-effectiveness and high strength. The primary focus of this research lies in the computational modeling of Fe-SMA strips utilized to reinforce damaged concrete structures. To achieve this, details from an experimental test are leveraged for the computational simulation of real-scale reinforced concrete beams that were first loaded to some level of damage, then released and strengthened, and subsequently retested. The strengthening approach involves the application of external Fe-SMA strips wrapping around the beams. This paper presents an original computational modeling setup that incorporates a switch option for the Fe-SMA material. This feature enables one to use a single simulation platform for the whole process. The significance of this method originates from its capacity to ensure a robust analysis that includes all simulation steps-testing unstrengthened beams, installing and heating Fe-SMA strips, and testing both damaged and strengthened beams-in a single, multi-step analysis. The computational simulation results were compared with the outcomes of the experimental test, revealing an acceptable level of agreement. The findings indicate a substantial increase in both shear strength and ductility as a result of the application of Fe-SMA strips. Additionally, parametric and mesh sensitivity studies were conducted. These aimed to investigate the mesh dependency of the model and to identify the optimal mesh size. Furthermore, variations in the details of the Fe-SMA strips, including thickness, width, quantity, and effect of applied temperature were explored to compare the outcomes of different applications of these strips.

18

Effects of Contamination with Gasoline and Diesel Oil on Shear Strength of Coarse Grained Soil

Brzeziński Bartłomiej, Olchawa Andrzej

Rocznik Ochrona Środowiska

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2023

|

Tom 25

222--227

EN

The paper presents research results into the influence of motor fuels on the shear strength of coarse-grained soil. The soil was classified following the unified soil classification system PN-EN ISO 14668-1 as saGr. The soil samples were artificially contaminated with three percentage ratios of motor fuels 5, 7.5 and 10% in relation to the dry mass of the soil skeleton. The test results have shown that motor fuel contamination significantly impacts the tested soil's mechanical properties. Increasing the content of impurities causes a significant decrease in shear strength parameters. For soil contaminated with 5%, 7.5% and 10% of motor fuel, i.e. gasoline or diesel, the angle of internal friction decreased by 8%, 15% and 20%, respectively. Along with the impurities increase, the soil's ultimate bearing capacity, calculated following EC-7, showed a dramatic decrease. The decrease was 40%, 57% and 66% respectively.

19

Behavior study of the steel plate girder with a cellular honeycomb web

Ammash Haider K., Shaffaf Noora N.

Przegląd Naukowy Inżynieria i Kształtowanie Środowiska

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2023

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Vol. 32, No. 2

101--116

EN

Based on the experimental test results of the authors, this investigation is concerned with the finite element analysis to examine and compare the load values and failure modes of the authors’ results. This research was conducted using the Abaqus software. The experimental work included the fabrication of twelve plate girders with honeycomb and flat web plate corrugation patterns, which were then tested under a single concentrated load at the midspan. According to the corrugation dimension or outer honeycomb web thickness, the honeycomb steel plate web girder is divided into three groups (60 mm, 80 mm and 100 mm). The specimens also involved plate girders with a flat web. The specimens were created with three lengths (600 mm, 1,200 mm and 1,800 mm). The Abaqus software was used in finite element models to simulate the concentrated load. The numerical results demonstrated that the 60 mm thick honeycomb web provides a greater load-bearing capacity and shear strength than other girders. The 20 mm honeycomb corrugation on the steel plate girder indicates the increased and improved shear resistance. The conclusion was that as the width of the corrugation increased, so did the steel web’s ultimate load and shear strength, resulting in a positive relationship between the critical shear buckling load of the web and the moment of inertia at the strong axis. When the dimension of the corrugation increases, the moment of inertia of the Y axis (Iy) decreases; thus, the plate girder will fail with a less critical buckling load (Pcr). Also, it can be concluded that as the steel plate thickness of the honeycomb web increases, the shear resistance increases as well. However, the spacing between the intermediate stiffener or the horizontal spacing of the web panel can enhance the shear resistance of honeycomb web girder if it was decreased due to increasing the action of tension field force that resists the diagonal tension developed at the web panel by the applied midspan concentrated force.

20

Ocena wpływu ekstremalnych temperatur utwardzania wyrobów do konstrukcyjnego łączenia materiałów na ich wybrane właściwości użytkowe

Wojnowski Damian, Bardan Magdalena

Przegląd Budowlany

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2023

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R. 94, nr 7-8

65--69

PL

Celem eksperymentu była ocena wpływu temperatury utwardzania na wybrane właściwości użytkowe wyrobów do łączeń konstrukcyjnych. Do badań wytypowano trzy kleje epoksydowe przeznaczone - w ramach naprawy konstrukcji betonowych - do przyklejania materiałów, takich jak np. maty z włókien węglowych, szklanych i aramidowych. Substraty, z których składają się poszczególne kleje, jak również przygotowane obiekty badawcze, kondycjonowano w warunkach laboratoryjnych oraz ekstremalnych temperaturach utwardzania, wytypowanych do projektu w oparciu o informacje znajdujących się w kartach technicznych wyrobów. Jako temperatury ekstremalne przyjęto maksymalną 35˚C i minimalną 10˚C wartość deklarowaną wspólną dla wytypowanych klejów. Przeprowadzono badania, których wyniki stanowią podstawowe kryterium oceny jakości połączeń klejowych, takie jak: wytrzymałość na ścinanie (przy różnych wartościach kąta nachylenia złącza), wytrzymałość na ściskanie i zginanie. Dodatkowo wykonano badanie przyczepności betonu starego do betonu starego, które pozwoliło określić, jaki wpływ ma temperatura utwardzania na połączenie kleju i betonu. Analiza uzyskanych wyników wykazała wpływ temperatury utwardzania wyrobów do łączeń konstrukcyjnych na ich wybrane właściwości użytkowe. Większy wpływ na obniżenie poziomu uzyskanych parametrów ma spadek temperatury utwardzania klejów do łączenia konstrukcyjnego do 10°C.

EN

The aim of the experiment was to evaluate the influence of the hardening temperature on selected performance properties of products for construction joints. Three epoxy adhesives were selected for the tests, intended - as part of the repair of concrete structures - for gluing materials such as carbon, glass and aramid fiber mats. The substrates, which make up the individual adhesives, as well as the prepared research objects, were conditioned in laboratory conditions and extreme hardening temperatures, selected for the project based on the information contained in the technical data sheets of the products. The maximum 35˚C and minimum 10˚C declared values shared by the selected adhesives were adopted as extreme temperatures. Tests were carried out, the results of which constitute the basic criterion for assessing the quality of adhesive joints, such as: shear strength (at different values of the angle of inclination of the joint), compressive and bending strength. In addition, the adhesion test of the old concrete to the old concrete was performed, which allowed to determine the influence of the hardening temperature on the bonding of the adhesive and concrete. The analysis of the obtained results showed the influence of the hardening temperature of products for construction joints on their selected performance properties. The decrease in the curing temperature of structural adhesives to 10°C has a greater impact on the reduction of the obtained parameters.