Lead Rubber Bearings (LRBs) represent one of the most widely employed devices for the seismic protection of structures. However, the effectiveness of the same in the case of curved bridges has not been judged well because of the complexity involved in curved bridges, especially in controlling torsional moments. This study investigates the performance of an LRB-isolated horizontally curved continuous bridge under various seismic loadings. The effectiveness of LRBs on the bridge response control was determined by considering various aspects, such as the changes in ground motion characteristics, multidirectional effects, the degree of seismic motion, and the variation of incident angles. Three recorded ground motions were considered in this study, representing historical earthquakes with near-field, far-field, and forward directivity effects. The effectiveness of the bi-directional behavior considering the interaction effect of the bearing and pier was also studied. The finite element method was adopted. A sensitivity study of the bridge response related to the bearing design parameters was carried out for the considered ground motions. The importance of non-linearity and critical design parameters of LRBs were assessed. It was found that LRBs resulted in a significant increase in deck displacement for Turkey ground motion, which might be due to the forward directivity effect. The bi-directional effect is crucial for the curved bridge as it enhances the displacement significantly compared to uni-directional motion.

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Singulation of seeds has been investigated extensively by researchers all over the world and a large number of precision seeding systems with design variations have been developed for different crops. A picking type metering mechanism was developed at CAET, AAU, Godhra, Gujarat, India. The performance of the picking type seed-metering device of a pneumatic planter was investigated under laboratory conditions to optimize the operating parameters for lady's finger seed. The picking of single seed the three operational parameters i.e. hole diameters for the nozzle: 1.0, 1.5, 2.5 and 3.0 mm; forward speed: 0.37, 0.56, 0.83, 1.11 and 1.30 m/s and vacuum pressure: 19.33, 39.32, 43.98, 58.64 and 68.63 kPa were selected for the study. The metering system of the planter was set to place the seed to seed spacing at 300 mm. The response surface methodology (RSM) technique was used to optimize the operational parameters of a precision planter. For optimizing the forward speed, vacuum pressure and nozzle size for developed machine was evaluated by examining the miss index, multiple index, quality of feed index and precision. The data obtained in the experiments were used to develop functions in polynomial form using multiple regression technique. The optimum value was found to be around 0.96 m/s, 36.25 kPa and 2.0 mm of forward speed, vacuum pressure and the holes diameter of nozzle, respectively. The most important variable that governs planting phenomenon is the combination of hole diameter of nozzle and vacuum pressure accounts 89.18 per cent.

Several design codes consider the non-linear response of a building by using one of the most important seismic parameters, called the response reduction factor (R). The lack of a detailed description of the R factor selection creates the need for a deeper study. This paper emphasises a methodology for the selection of a proper R factor based on resilience aspects. Unsymmetrical/irregular buildings have become the most common in recent times due to aesthetic purposes. However, because of the complexity due to the torsional effect, the selection of the R factor is even more difficult for this type of building. Therefore, a high-rise G+10-storey L-shaped building is herein considered. The building has re-entrant corners based on the structural/plan arrangement. Different R factors were used in the building design, considering buildings subjected to both unidirectional and bidirectional seismic loading scenarios. The building response with respect to various R factors (R equal to 3, 4, 5 and 6) in terms of its performance level, functionality, damage ratio and resilience was assessed at two design levels, i.e., design basic earthquake (DBE) and maximum considered earthquake (MCE). The study concludes that, considering the above criteria along with the resilience aspect, a maximum R factor up to 4 can be recommended for unidirectional loading, whereas for bidirectional loading, the maximum recommended R factor is 3.

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