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Effect of Atmospheric Pressure Oxygen Plasma treatment on Bonding Characteristics of Basalt Fibre Reinforced Concrete

Nandagopal K. R., Selvakumar A., Raja D.

Fibres & Textiles in Eastern Europe

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2021

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Vol. 29, no. 4 (148)

90--93

EN

In this research work, the bonding characteristics of plasma treated basalt fibres were analysed by employing the fibre pull-out test. 80 samples were prepared with two different spans of basalt fibres (such as 25 mm and 50 mm) and four levels of embedded length (10, 15, 20 and 25) inside standard M20 grade concrete. Debonding and bonding characteristics of the plasma treated fibres were compared with raw basalt fibres through the fibre pull-out test. The plasma treated and raw basalt fibres were characterised through Field emission scanning electron microscope (FESEM) and Fourier transform infrared (FTIR) analysis. It was observed that confirmation of the presence of hydroxyl groups on the basalt fibre surface was realised through the FTIR test and that there was higher adsorption of concrete particles by the plasma treated basalt fibres through FESEM. The de bonding and fibre pull-out energy of the plasma treated basalt fibres were improved by about 9% and 10% compared with 25 mm and 50 mm raw basalt fibres. From the observation above, it can be stated that the Surface modification of basalt fibre may lead to a change in the debonding and pull-out energy level.

PL

W pracy zostały przeanalizowane właściwości wiązania włókien bazaltowych poddanych obróbce plazmowej. Przygotowano 80 próbek dwóch różnych rodzajów włókien bazaltowych: 25 mm i 50 mm z czterema poziomami zatopionej długości (10, 15, 20 i 25) wewnątrz standardowego betonu klasy M20. Charakterystyki odklejania i wiązania włókien poddanych obróbce plazmowej porównano z surowymi włóknami bazaltowymi w teście wyciągania włókien. Obrobione plazmowo i surowe włókna bazaltowe scharakteryzowano za pomocą skaningowego mikroskopu elektronowego z emisją polową (FESEM) i analizy w podczerwieni z transformacją Fouriera (FTIR). Potwierdzenie obecności grup hydroksylowych na powierzchni włókna bazaltowego uzyskano za pomocą testu FTIR. Na podstawie wyników analizy FESEM stwierdzono, że nastąpiła większa adsorpcja cząstek betonu przez poddane obróbce plazmowej włókna bazaltowe. Rozwarstwianie i energia wyciągania włókien bazaltowych poddanych obróbce plazmowej uległy poprawie o około 9% i 10% w porównaniu z surowymi włóknami bazaltowymi 25 mm i 50 mm. Na podstawie przeprowadzonej obserwacji stwierdzono, że modyfikacja powierzchni włókna bazaltowego może prowadzić do zmiany poziomu energii odklejania i wyciągania.

2

Investigation of pullout strength in different designs of pedicle screws for osteoporotic bone quality using finite element analysis

Yang Shih-Chieh, Liu Pao-Hsin, Tu Yuan-Kun

Acta of Bioengineering and Biomechanics

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2019

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Vol. 21, no. 3

57--66

EN

The purpose of this study was to investigate pullout strength of three types of pedicle screws with and without cement augmentation in osteoporotic bone using finite element analysis. Methods: Twelve 3D finite element models were created to investigate the effect of pullout strength when comparing between pedicle screw types and bone cement clouds. The bottom side of bone block model was constrained and U-shape head was applied 1 mm in direction of longitudinal axis of pedicle screw to perform pullout resistance. The material properties of the FEA was set as linear elastic, homogenous, isotropic condition. The element sensitivity of convergence testing has been performed and variation of the sequential analytical results was less than 3%. Results: The results showed that the maximum total reaction force (133.8 N) was detected in the model of cannulated pedicle screw combined with a central pin with 4 ml cement augmentation, but, in contrast, the minimum total reaction force (106.8 N) was discovered in the model of cannulated pedicle screw without cement. A strong relationship (r = 0.9626) is found in comparison with the biomechanical results between pullout strength of sawbone testing and reaction forces of the FEA. Conclusions: The study concludes that the cannulated pedicle screw can not only provide an inner guider for cement flow and increase bending resistance (deflection effect) when a central pin is selected, but also can improve the pullout strength in the osteoporotic bone to add cement augmentation. The design of the cannulated pedicle screw is suggested for poor bone quality to change pullout failure.

3

Pullout evaluation of sawbone experiment in different types of pedicle screws combined with bone cement augmentation for severe osteoporotic spine

Yang S.-C., Liu P.-H., Tu Y.-K.

Acta of Bioengineering and Biomechanics

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2018

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Vol. 20, no. 2

55--64

EN

Purpose: The conventional screw is unable to provide enough screw-bone interface strength for osteoporotic cencellous bone, and complications resulting from loosening or failure of the implants remain a significant clinical problem. Hence, the purpose of this study is to investigate pullout strength and energy in three types of the pedicle screws, including conventional solid pedicle screw, cannulated pedicle screw, and cannulated pedicle screw with a central pin, using osteoporotic sawbone test block with different bone cement volumes through pullout force testing. Methods: The control group (n = 15) of the osteoporotic sawbone test block includes groups A, B, and C to reflect three types of the pedicle screws without bone cement augmentation. The cemented group (n = 45) of the osteoporotic sawbone test block includes groups D1, D2, D3, E1, E2, E3, F1, F2, and F3 to reflect three types of the pedicle screws with PMMA bone cement of 2, 3, and 4 mL augmentation. Results: The results showed that the pullout strength and energy in the cemented group were significantly larger than that in the control group. Moreover, the best performances of the pullout strength and energy in the cemented group were evidenced obviously in the case of cannulated pedicle screw with a central pin with 4 mL bone cement augmentation. Conclusions: This study concludes that cement argumentation in the cannulated pedicle screw with a central pin can increase a pullout strength of pedicle screw for severe osteoporotic patients while bone cement of injective volume is limited.