Impact of a falling mass on a beam | |
| Author | Pulmano, Victor A. |
| Call Number | AIT Thesis no. 31 |
| Subject(s) | Girders|xTesting Structural dynamics |
| Note | A thesis submitted in partial fulfillment if the requirements for the degree of Master of Engineering in the SEATO Graduate School of Engineering, Bangkok, Thailand. |
| Publisher | Asian Institute of Technology |
| Abstract | The central impact of a free falling solid steel sphere on a simply-supported steel beam was experimentally investigated# A sensitive crystal load cell and a displacement transducer were used to measure the dynamic force and displacement, respectively# The output voltages of these measuring instruments were fed into a double sweep oscilloscopeo Simultaneous and separate traces of the Torce-time and displacement-time curves were recorded by a camera, with its lens open and film stationary while the electron beams were sweeping the screen of the oscilloscope# The dynamic load-deflection curves were plotted graphically up to the point of maximum deflection only# The resulting curves show a very considerable deviation with static load-deflection curves within the elastic limit of the material# A simplified differential equation for the motion of a prismatic beam, which neglects shear and rotatory inertia, is solved by the method of Laplace transformation. The solution yields the subsidiary deflection equations for simply-supported and cantilever beams due to a concentrated load which varies arbitrarily with time. An impulse or a Dirac-delta function and a step function were assumed as the time variation of the applied force on the simply-supported beam. Graphs of the resulting deflection equations were superimposed on the experi¬ mental displacement-time curves# The delta function gives a very close approximation by assuming the value of the impulse about 20% of the total area under the experimental force-time curve. The step function gives a poor approximation* |
| Year | 1962 |
| Type | Thesis |
| School | Student Research Before 1979 |
| Department | Other Field of Studies (No Department) |
| Academic Program/FoS | Thesis (Year <=1979) |
| Degree | Thesis (M.Eng.) - SEATO Graduate School of Engineering |