Apparatus of staged resonant frequency vibration of concrete
US5527175A · kind A · utility
Inventors
Key dates
| Filing date | Dec 3, 1993 |
| Grant date | Jun 18, 1996 |
| Priority date | — |
| Expiry date | Dec 3, 2013 |
Classification
- Technology area (CPC E)Fixed Constructions
- CPC primaryE04G21/066
- WIPO fieldCivil engineering
- WIPO sectorOther fields
Abstract
Vibrational energy introduced into plastic concrete structures, such as concrete slabs, decks and similar or related concrete structures, at or near the natural resonant frequency of the liquid concrete mass, expedites the consolidation and setting of the concrete. A vibrating apparatus imparts controlled vibrations either onto the surface or beneath the surface of the concrete mass in sequential stages, the frequency of vibrations generally increasing with each subsequent stage, corresponding to the increase in the natural resonant frequency of the progressively-narrowing liquid concrete at the top of the structure. The relatively more consolidated and more dry concrete (typically near the bottom of the slab) is substantially unaffected by the non-resonant frequencies vibrations. In one modification, sensors determine the resonant frequency of the liquid concrete mass during each pass of the vibrator apparatus, and the frequency of the vibrating member is automatically adjusted, accordingly. The number of stages, the amplitude of the vibrations, the physical orientation of the vibration-producing apparatus, the time duration in each stage, is variable depending upon the physical c…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.