Comparative Studies on the Behaviour of Flat Panels Made of GRP Under Static and Dynamic Loads

Glass reinforced plastic, so called GRP, is a composite material made of glass strands called fibbers woven together to create a flexible fabric. GRP is a lightweight material with many and diverse applications ranging from the manufacture of reservoirs for different liquids to the manufacture of boats, yachts, chairs and even children playground furniture. The behaviour of this material under static and dynamic loads is still raising interest from the scientific community and a large number of researchers. This continued interest is due to the material versatility for different applications depending on its manufacture process that has a significant weigh-in in the material mechanical properties. These resulting mechanical properties need to be carefully analysed and benchmarked prior to using the obtained material in commercial applications. The scope of this research study is to analyse the behaviour of glass reinforced plastic plate panel with reinforcements on one and two directions under static and dynamic loads employing both experimental and numerical methods for results validation. The methods used in this research study for the dynamic loads can also be applied successfully to other composite materials. Additionally, the stress plots have been analysed in iteration in order to ensure the most optimal reinforcement pattern.

Optimasi Dimensi Connecting Rod Al2024 dan Tulangan Baja 4340 pada Kawasaki Ninja 150 R Menggunakan ANSYS

ABSTRAKConnecting rod berfungsi menghubungkan piston ke crankshaft, sistem ini membentuk mekanisme sederhana yang mengubah gerak lurus menjadi gerak melingkar ataupun sebaliknya. Umumnya connecting rod dirancang berbenruk I agar kuat dan ringan dengan material baja. Pengurangan massa pada connecting rod dapat mengurangi momen inersia engine, meningkatkan performa dan fuel efficiency engine. Penelitian ini bertujuan untuk mendapatkan dimensi optimum connecting road menggunakan material Al 2024 dan tulangan baja 4340.Dimensi optimum harus dapat menahan tegangan dan regangan maksimum yang terjadi pada connecting rod ketika menerima beban tekan dan tarik. Penelitian dilakukan dengan melakukan varisi dimensi profil I dan bentuk tulangan dengan dimensi lain menyesuaikan spesifikasi connecting rod Kawasaki Ninja 150 R. Hasil penelitian memperlihatkan bahwa connecting rod dengan profil I, bentuk tulangan webbing merupakan tulangan paling optimal dengan ketebalan 8 mm dengan berat total 0,12 Kg.Kata kunci: connecting rod, tulangan baja, Al2024, ANSYSABSTRACTThe connecting rod serves to connect the piston to the crankshaft; this system forms a simple mechanism that converts straight motion into circular motion or vice versa. Generally, connecting rods are designed to be made in order to be strong and lightweight with steel material. Reducing the mass of the connecting rod can reduce the moment of engine inertia, improve the performance and fuel efficiency engine. This study aims to obtain the optimum dimensions of the connecting road using Al 2024 material and steel reinforcement 4340. The optimum dimension must be able to withstand the maximum stress and strain that occurs in the connecting rod when receiving compressive and tensile loads. The study was conducted by varying the dimensions of profile I and shape of reinforcement with other dimensions adjusting the specifications of the connecting rod Kawasaki Ninja 150 R. The results showed that the connecting rod with profile I, the form of webbing reinforcement was the most optimal reinforcement with a thickness of 8 mm and total mass 0,12 kg.Keywords: connecting rod, reinforcement steel, Al2024, ANSYS.

Topology Optimization of the Fiber-Reinforcement of No-Tension Masonry Walls

An innovative approach is proposed to define the optimal fiber-reinforcement of in-plane loaded masonry walls, modeled as linear elastic no-tension (NT) bodies. A topology optimization formulation is presented, which aims at distributing a prescribed amount of reinforcement over the wall, so as to minimize the overall elastic energy of the strengthened element. Perfect bonding is assumed at the wall-reinforcement interface. To account for the negligible tensile strength of brickwork, the material is replaced by an equivalent orthotropic material with negligible stiffness along the direction (s) undergoing tensile principal stress (es). Compressive principal stresses in the reinforcement are not allowed. A single constrained optimization problem allows both the equilibrium of the NT body to be enforced, and the optimal reinforcing layout to be spotted out, without any demanding incremental approach. Some preliminary numerical examples are shown to assess the capabilities of the proposed procedure and to identify the optimal reinforcement patterns for common types of masonry walls with openings.