I did a lot of work in the late 80s/early 90s with both the standard
(4.5kg) Clegg Hammer and a larger version we designed and had constructed.
We looked at integrating the accelerometer signal twice etc to determine a
'displacement' and trying to determine a stiffness parameter. This work was
on compacted granular soils predominantly. There are problems associated
with high frequency noise in the signal and also the distinction between
elastic and plastic strains under the clegg hammer impact, and many issues
relating to the small diameter and rapid load rate.

I have also carried out a lot of work with portable dynamic plate bearing
tests for monitoring roads and reinstatements during construction, and am
currently doing research with the English Hockey Association into synthetic
pitch construction and monitoring. We are evaluating a 2.25kg Clegg as part
of this work.
You are using the 0.5kg Clegg I presume, perhaps more related to ball
bounce than player-surface interaction?

Paul Fleming



At 12:37 21/02/02 -0800, Russell Young wrote:
>   Hello   Has any one got experience of using a Clegg hammer  to measure
>not only peak deceleration on a surface but also the pattern of
>deceleration, apparently this piece of kit can be modified and linked to an
> oscilloscope. We currently use it to measure "g" in the range of 200 -
>1000 on  cricket wickets.


Dr Paul R Fleming
Lecturer in Geotechnical Engineering
Dept. of Civil and Building Engineering
Loughborough University
Loughborough
Leics LE11 3TU
Tel: 01509 222616 (Direct)
Tel: 01509 222637 (Secretary)
Tel: 01509 222884 (Dept General Office)
Fax: 01509 223981 (Department)
http://www.lboro.ac.uk/departments/cv/research/profiles/staff/27.html