DTI Awards Research Project for New Shear Wave Source
A consortia comprising Soil Mechanics, G D S Instruments Ltd and the University of Newcastle has been awarded an £86,100 research contract by the Department of Trade and Industry under it’s Link Programme for Sensor and Sensor Systems. The project, given the abbreviation ‘HORSA,’ involves the development of an integrated downhole seismic source which can provide both horizontally and vertically polarised shear waves primarily for use in crosshole seismic testing. This is currently the only research project being funded by the DTI under it’s Link Sensors Programme in civil engineering or earth science.
The objective is to develop a simple and versatile state-of-the-art investigation technique that will be a robust, efficient and repeatable seismic source that can be used to a depth of 100 metres within 0.1 metre diameter boreholes.
It is anticipated that the primary use of the HORSA system will be for the simultaneous determination of both the vertical and horizontal shear wave velocity of the ground from which the in situ vertical and horizontal dynamic moduli and hence the anisotropic nature of the ground can be determined. This data can then be used in numerical modelling of deformations around below ground structures.
Determination of the shear wave velocity of the ground is required for seismic risk assessment. The HORSA sonde will be a valuable investigation tool because horizontally polarised shear waves more closely model shear waves propagated by earthquakes than vertically polarised shear waves..
The project was commenced in July 2001 and has a duration of three years. The work comprises four stages:
- Response evaluation with development of prototype sonde.
- Field evaluation of prototype.
- Commercial development to produce a robust marketable product.
- Publication of technical papers and marketing.
Currently the project is progressing through Stage 1 and it is anticipated that a prototype sonde will commence field evaluation early in 2002. |
