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Badania doświadczalne wytrzymałości betonu zawierającego zmielony popiół z osadnika

Yuvaraj K., Ramesh S.

Cement Wapno Beton

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2021

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R. 26, nr 3

253--262

PL

W obecnych czasach zużycie energii elektrycznej gwałtownie wzrasta z każdym rokiem, ze względu na industrializację. Węgiel jest surowcem do produkcji energii elektrycznej w elektrociepłowniach. Szczególnie duża ilość niewykorzystanego popiołu jest wyrzucana do osadników, co stanowi poważny problem dla wielu krajów rozwijających się. Ponadto składowanie popiołu w osadnikach powoduje zagrożenia dla środowiska, takie jak zanieczyszczenie gleby i wody. Zidentyfikowanie realnej alternatywy dla wykorzystania popiołu z osadników staje się potrzebą chwili, aby uniknąć tych zagrożeń dla środowiska. W niniejszej pracy badawczej podjęto próbę częściowego zastąpienia cementu popiołem z osadnika jako dodatku mineralnego w betonie, co w znacznym stopniu ograniczy szkodliwy wpływ popiołu z osadnika na środowisko. Popiół ten zmielono do wielkości 45 μm i użyto go do zastąpienia cementu w betonie w proporcjach 5, 10, 15, 20 i 25% masy. Przeprowadzono badania wytrzymałości na ściskanie, zginanie oraz rozciąganie przy rozłupywaniu uzyskanych betonów. Wyniki badań wykazują, że dodatek 10% popiołu z osadnika znacznie zwiększył wytrzymałość betonu w wieku 7, 28, 56 i 90 dni.

EN

In the present era, the consumption of electricity has increased rapidly with each passing year, due to the industrialization. Coal is a raw material for the production of electricity in the thermal power stations. Particularly, a large amount of unused ash is dumped in ponds, which are major problem concerning many developing countries. Further, dumping of ash in ponds causes environmental hazards effects such as soil, land and water pollution. Identifying a viable alternative to utilize pond ash becomes a necessity, to avoid these environmental hazards. In this research work, an attempt has been made to partially replace cement by the pond ash as a supplementary cementitious material [SCM] in concrete, which will considerably reduce the hazardous effects of pond ash, to the environment. The pond ash was ground to 45 μm and it was used to replace the cement in concrete by proportions of 5, 10, 15, 20 and 25% by mass. Test on compressive strength, split tensile strength and modulus of rupture were conducted on concrete mixes. The result indicate that the addition of 10% pond ash to concrete significantly increased the strength properties of the concrete at the age of 7, 28, 56 and 90 days.

2

Performance Analysis of Wheel and Rail Contact by Nature of Material Characteristics - a Contact Mechanics Approach

Gandhi V. C. S., Kumaravelan R., Ramesh S., Thanmanaselvi M., Sriram K.

Mechanics and Mechanical Engineering

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2014

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Vol. 18, nr 1

11--24

EN

The study aims on by contact analysis of a cylindrical wheel and a rail structure of I–section with considering the material properties of an elastic–plastic adhesive frictional contact. Different materials are considered for the analysis based on Young’s modulus and yield strength ratio (E/Y). The contact analysis of this model has been carried out using analysis software ANSYS. The simulation results shows that the maximum stress and strain developed at a point near by the contact edge for lower E/Y value of material and move along the center of a straight line in the contact region between wheel and rail if the E/Y value increases. The results are compared with the basic contact model and shows that good agreement for the nature of material dependence.

3

Performance Analysis of Motor Cycle Helmet under Static and Dynamic Loading

Gandhi V. C. S., Kumaravelan R., Ramesh S., Venkatesan M., Ponraj M. R.

Mechanics and Mechanical Engineering

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2014

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Vol. 18, nr 2

85--96

EN

Each year nearly nine hundred persons die in head injuries and over fifty thousand persons are severally injured due to non wearing of helmets . In motor cycle accidents, the human head is exposed to loads exceeding several times the loading capacities of its natural protection. In this work, an attempt has been made for analyzing the helmet with all the standard data. The simulation software ‘ANSYS’ is used to analyze the helmet with different conditions such as bottom fixed-load on top surface, bottom fixed– load on top line, side fixed–load on opposite surface, side fixed–load on opposite line and dynamic analysis. The maximum force of 19.5 kN is applied on the helmet to study the model in static and dynamic conditions. The simulation has been carried out for the static condition for the parameters like total deformation, strain energy, von Mises stress for different cases. The dynamic analysis has been performed for the parameter like total deformation and equivalent elastic strain. The result shows that this values are concentrated in the retention portion of the helmet. These results has been compared with the standard experimental data proposed by the BIS and well within the acceptable limit.