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Fibre-reinforced concrete cannot replace the ordinary reinforced concrete. However, there are areas of use in which fibre-reinforced concrete can be used alternatively or in addition to the ordinary reinforced concrete, offering several advantages, some of that being presented in this study. The basic idea is that reinforcements create a multi-directional �mesh� within the cementitious matrix that will make concrete stronger. In fact, adding the fibrous material to concrete will increase the strength. In this sense, the micro-fibres primarily work to prevent micro- or shrinkage cracking, which mostly occurs during the initial curing process of the concrete, or those critical first 28 days. By contrast, the macro-fibres provide load-bearing strength after the concrete cracks. But, in fact, the subject is more complex. The types and size of fibres, their distribution and orientation are a hugely complex topic. Fibres, of whatever nature, have been found to improve the properties of concrete. Fibre-reinforced concrete provides an alternative to conventional reinforcement, with the advantage of time and reduced costs of performing maintenance work. The complexity of various fibre use presents challenges for the construction sectors that may be beyond current levels of expertise. In this study, particularities of concrete reinforced with polymer fibres are presented. Also, a comparative study is presented, based on our previous works in area of the concrete reinforcing with recycled polyethylene terephthalate (PET).

In engines pistons are very important parts to produce power. Piston fail mainly due to mechanical stresses and thermal stresses. An analysis of thermal stress and damages due to application of temperature is presented and analysed in this work. Aluminium alloy have been selected for thermal analysis of piston. Results are shown and a comparison is made to find the most suited design Analysis of piston crown is done with boundary conditions, which includes pressure on piston head during working condition and uneven temperature distribution from piston head to skirt. There are four types of piston crown that has been analysed in this project. The CAD model is created using CATIA software. CAD model is then imported into ANSYS software for geometry and meshing purpose. Complete design is imported to ANSYS 15 software then analysis is performed. I. INTRODUCTION The modern trend is to develop IC Engine of increased power capacity. One of the design criteria is the endeavor to reduce the structures weight and thus to reduce fuel consumption. This has been made possible by improved engine design. These improvements include increased use of lightweight materials, such as advanced ultra-high tensile strength steels, aluminum and magnesium alloys, polymers, and carbon-fiber reinforced composite materials. The integration of lighter weight materials is especially important if more complex parts can be manufactured as a single unit. In the next 10-20 years, an additional 20-40% reduction in overall weight, without sacrificing safety, seems to be possible. Withstand loads tending to elongate. In other words, compressive strength resists compression. Compressive strength is often measured by universal testing machine. In this work Eutectic Al Alloy (Si 11-13%) was taken as piston material. Initially thermal and structural analysis was performed on Al Alloy piston without silicon nitride crown and then with silicon nitride crown using the software ANSYS. Then the results obtained are compared. The comparison of results indicated that the piston which is arranged by silicon nitride crown is better to withstand high thermal and structural stresses than the piston which is not arranged by silicon nitride crown. The present work has been undertaken with the following objective, To design an IC engine (piston and piston ring) by using CATIA V5 R20 software, To perform the thermal analysis (of piston and piston ring) using ANSYS 15 software. Engine pistons are one of the most complex components among all automotive and other industry field components. The engine can be called the heart of a vehicle and the piston may be considered the most important part of an engine. There are lots of research works proposing, for engine pistons, new geometries, materials and manufacturing techniques, and this evolution has undergone with a continuous improvement over the last decades and required thorough examination of the smallest details. Notwithstanding all these studies, there are a huge number of damaged pistons. In this analysis project we...

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