Portal frame

About: Portal frame is a research topic. Over the lifetime, 1778 publications have been published within this topic receiving 7210 citations.

Hierarchical speed governing device of fork truck portal frame

Abstract: The utility model relates to a hierarchical speed governing device of a fork truck portal frame, which aims to solve the problem of the forklift series fork truck applied in the prior market that the lifting speed of the portal frame is hard to control, and safety hazard lurks therein, and has a structure that height sensors are fixedly arranged on the two corresponding guide rails of the portal frame, the height sensors are in signal connection with the input end of a programmable controller, one output end of the programmable controller is in signal connection with a monitor, the other output end of the programmable controller is in signal connection with an adjustable speed circuit, and the adjustable speed circuit is in signal connection with a drive motor The utility model adopts the height sensors to monitor the lifting height of the portal frame, and adopts the height sensor signals after being processed by the programmable controller to adjust the lifting speed of the portal frame, thereby ensuring the safety and stability in loading cargo

Neural Networks in Updating of Dynamic Models with Experimental Verification

Abstract: This paper presents the application of artificial neural networks in updating of dynamic models of engineering structures. There are presented examples of updating of two models: a model of a beam hung on two strings and a model of a portal frame. There are used multi-layer feed-forward networks and networks with radial basis function, the input vectors consist of preprocessed data obtained from the measurements done on a laboratory models of considered structures.

Damage propagation in reinforced concrete frames under external blast loading

Abstract: Iconic and significant buildings are the common target of bombings by terrorists causing large numbers of casualties and extensive property damage. Recent incidents were external bomb attacks on multi-storey buildings with reinforced concrete frames. Under a blast load circumstance, crucial damage initiates at low level storeys in a building and may then lead to a progressive collapse of whole or part of the structure. It is therefore important to identify the critical initial influence regions along the height, width and depth of the building exposed to blast effects and the structure response in order to assess the vulnerability of the structure to disproportionate and progressive collapse. This paper discusses the blast response and the propagation of its effects on a two dimensional reinforced concrete (RC) frame, designed to withstand normal gravity loads. The explicit finite element code, LS DYNA is used for the analysis. A complete RC portal frame seven storeys by six bays is modelled with reinforcement details and appropriate materials to simulate strain rate effects. Explosion loads derived from standard manuals are applied as idealized triangular pressures on the column faces of the numerical models. The analysis reports the influence of blast propagation as displacements and material yielding of the structural elements in the RC frame. The effected regions are identified and classified according to the load cases. This information can be used to determine the vulnerability of multi-storey RC buildings to various external explosion scenarios and designing buildings to resist blast loads.

Full-automatic unloader

Abstract: The utility model provides a full-automatic unloader which comprises a frame with moving wheels. The full-automatic unloader is characterized in that a lifting portal frame is disposed on the frame, a telescoping clamp holder is disposed on a top cross beam of the lifting portal frame, and a support is disposed on the middle cross beam of the lifting portal frame. Goods can be held by means of clamping conveniently through the lifting portal frame, and the telescoping clamp holder and the support thereon, and moved into a storage along with the frame, and accordingly full-automatic unloading of goods is achieved. By cooperation of the clamp holder and the support, damage of goods can be avoided effectively, investment of fixed assets such as forklifts, and manpower resources is reduced, labor intensity is lowered greatly, unloading efficiency is improved, and full-automatic unloading is achieved.

Simple and easy type horizontal hand sawing machine

Abstract: The utility model relates to a simple and easy type horizontal hand sawing machine, this machine simple structure, low in production cost, but the base adopts detachable structure, convenient transport, control simply, degree of automation is high, operates steadily, and is fast efficient, saw cuts panel roughness height, but power structure firewood electricity is dual -purpose, and environmental suitability is strong. The utility model provides a simple and easy type horizontal hand sawing machine comprises base, portal frame, aircraft nose. Detachable structure install guide rail, chain on the base, but the base is adopted in direct in the horizontal position in the ground of base, on the portal frame stood on the base guide rail, the portal frame bottom set up the advance and retreat motor, and aircraft nose elevating gear, opposite side top design coolant tank are installed to portal frame one side, the aircraft nose is installed in the middle of the portal frame, and the aircraft nose both ends set up initiative flywheel and passive flywheel, and main motor direct mount is the top in the middle of the aircraft nose, and can conveniently pull down.