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This study uses numerical simulation to explore the performance of a portable bamboo girder designed for emergency scenarios and compares it to its steel counterpart. It underscores bamboo's appeal, offering a lightweight, quickly deployable, and eco-friendly alternative to steel. The research aims to assess bamboo's viability in emergency bridge construction, utilising SOLIDWORKS and ANSYS to create and simulate bamboo and steel girders. A bamboo girder aimed at humanitarian assistance and disaster relief (HADR) operations was analysed through ANSYS software under a Toyota Hilux truck's weight. Material properties, loads, and boundary conditions were defined for an accurate simulation. Three individual bamboo culms were tested in four-point flexural experiments, and the results revealed a modulus of elasticity of 14583 MPa and a local failure due to crushing and splitting with an ultimate strength of 263 MPa. Finite element analysis results indicated that the bamboo girder had a stress of 85.56 MPa and a deflection of 84.68 mm. Although the steel girder showed lower deflection, it had significantly higher stresses and weighed 180% more than the bamboo version. The bamboo girder's deflection surpassed the recommended limit under a fully loaded truck, indicating room for improvement. However, stress analysis revealed that the bamboo's structural integrity remained below its design strength. Conversely, the steel girder exhibited higher stresses and considerably greater weight. Despite deflection concerns, the bamboo girder demonstrated structural soundness and lower weight compared to steel. This positions it as a viable solution for swift emergency deployment, warranting further refinement for enhanced performance. [ABSTRACT FROM AUTHOR]

This paper presents control characteristic of an impact isolator featuring a magneto-rheological elastomer isolator device (MREID). The developed MREID is analysed in term of its magnetic intensity to produce a large of MR effect that controlled by the input current. In order to control the input current, the hybrid skyhook active force control (HySAFC) is proposed. The HySAFC is used to track the signal based on the force obtained from the feedback of the force sensor and accelerometer. However, the control output of the HySAFC is desired force of the current generator which is designed using the inverse adaptive neuro-fuzzy inference system (ANFIS). Then, the selection of the input current using the IF–THEN rules depend on desired force and impact energy for current generator. Next, for the development of control structure, the impact isolation system is formulated and the impact isolation test rig is used to perform the experimental validation process. The validation assessment of HySAFC is experimentally realized, and the control responses, namely such as jerk, accelerations and transmitted forces as well as the impact isolation system are presented in the time domain. Finding of this study, the HySAFC is able to improve the MREID performance for impact loading application in simulation and experiment and capable in providing fast response when impact occurred. [ABSTRACT FROM AUTHOR]

Small-scale blast tests were carried out to observe and measure the influence of sandy soil on explosive blast intensity. The tests were carried out to simulate the blast impact imparted by an anti-vehicular landmine on a vehicle with reference to light armoured vehicles. A steel apparatus with a scale factor of 1:10 and weighing about 22 kg was used to represent the size and weight of a vehicle, and a mass of 20 g high explosive charge was used as a surrogate landmine. The observations and measurements were made by optical method using a high-speed video camera. The time of occurrence of the three phases of detonation in soil for upward translation time of the test apparatus was recorded. The recorded flight time and peak height reached by the apparatus was used to determine the energy transfer and initial velocity. The data for detonation in sandy soil was compared with those for air blast detonation. At an identical stand-off distance, the blast intensity of detonation in sandy soil is higher than that of air blast detonation. Based on the optical observation and quantified data, the effect of soil in amplifying blast intensity is apparent and may be attributed to the effect of soil funnelling on blast wave and from the impact of soil ejecta. [ABSTRACT FROM AUTHOR]

For many years glass has been one of the most widely used construction materials for building facades. However, glass as a building material is very brittle, when explosion occurs, the air blast pressure, typically fractures glass windows, which might kill people and damage the surrounding areas. Evidence obtained from several terrorist attacks on buildings facades worldwide support this view. Currently, blast resistant glass panels are produced using polyvinyl butyral (PVB) interlayers and manufactured using the lamination process. This process requires heating and also an autoclave system. Using this procedure is expensive and is also not environment-friendly. Thus, researchers from the National Defence University of Malaysia (NDUM) collaborated with a glass manufacturer in Malaysia, Secuglass Sdn. Bhd. to develop a blast resistant glass panel, using green manufacturing process, which is more cost effective and environment friendly. This process does not require heating as well as an autoclave for the lamination. With this new manufacturing process uses polyurethane resin as an interlayer to provide protection against blast explosions. In this process, the polyurethane resin is poured into the cavity between two sheets of glasses that are held together until the resin cures. In this research, the glass panel produced from this process was tested for resistance against blast loading by using actual explosives. A field blast test was conducted on the laminated glass with polyurethane resin as an interlayer. The test was carried out in accordance with the ASTM F 1642-04 international testing standard for blast resistant glazing. The blast test results showed that using the laminated glass with polyurethane resin interlayer by using the green manufacturing process, the blast was able to withstand the peak overpressure of 305.09 kPa and reflected pressure of 4,688.43 kPa. In conclusion there is a potential for this manufacturing process to be used in the production of blast resistant glazing with polyurethane resin as an interlayer. [ABSTRACT FROM AUTHOR]

An improvised explosive device is regarded as one of the primary threats that can cause fatalities to armoured vehicle occupants. Upon detonation, the shock wave injures the crews as they are in direct contact with the blast impact through their feet and seating position. It is crucial to disperse the shock wave within a short time thus reducing the potential injury towards the vehicle's occupants. Traditional experimental processes typically use an actual vehicle and specialised anthropometric test dummy which is costly and non-repeatable if the asset is damaged during tests. This paper presents a scaleddown blast testing approach which comprises of an instrumented general-purpose dummy and a blast capsule. The capsule was designed to accommodate dummy at different seating position and a recumbent position. The main structural component of the blast capsule was designed and analysed using the strength of materials principle. Accelerometers were installed on specific areaof the blast capsule and an instrumented dummy for data measurement. The blast testing was performed using PE4 and at a fixed standoff distance under the capsule hull. Results have shown that the measured data have similarity in terms of shock history curves with other published works. Results obtained can also be used in validation of future simulation work. [ABSTRACT FROM AUTHOR]

This paper presents the results of the experimental data and simulation on the performance of hybrid steel fiber reinforced concrete (HSFRC) and also normal reinforced concrete (NRC) subjected to air blast loading. HSFRC concrete mix consists of a combination of 70% long steel hook end fibre and also 30% of short steel hook end fibre with a volume fraction of 1.5% mix. A total of six concrete panels were subjected to air blast using plastic explosive (PE4) weighing 1 kg each at standoff distance of 0.3 meter. The parameters measured are mode of failure under static and blast loading and also peak overpressure that resulted from detonation using high speed data acquisition system. In addition to this simulation work using AUTODYN was carried out and validated using experimental data. The experimental results indicate that hybrid steel fiber reinforced concrete panel (HSFRC) possesses excellent resistance to air blast loading as compared to normal reinforced concrete (NRC) panel. The simulation results were also found to be close with experimental data. Therefore the results have been validated using experimental data. [ABSTRACT FROM AUTHOR]