GROUND ANCHORS - Australian Geomechanics Society

108 Pages·2011·5.36 MB·English

GGRROOUUNNDD AANNCCHHOORRSS –– tthhee
iimmppoorrttaannccee ooff mmaaiinntteennaannccee aanndd
iinnssppeeccttiioonnss aanndd ssoommee rreecceenntt
ddeevveellooppmmeennttss
presentation by
Dr Devon Mothersille
SBMA Ltd
FEBRUARY 2011
Tonight’s presentation
Some special applications
The importance of maintenance and
inspections
Changes in European Standards
Recent developments
Final Remarks
INTRODUCTION
AND
BACKGROUND
TERMINOLOGY
Figure 1 from EN 1537:2000 - Sketch of a ground anchor
(details of anchor head and head protection omitted)
GRGORUONUDNDANACNHCOHRORMAMRAKREKTESTESCETCOTROSRS
SSEECCTTOORR 11
 Rockboltsandsoil  Lowcapacityground
nails anchors
 Lengthsupto10m  Lengthsupto12m
Loadsupto100kN  Loadsupto500kN
GROUND ANCHOR MARKET SECTORS
SECTOR 1
 Rockboltsandsoil  Lowcapacityground
nails anchors
 Lengthsupto6m  Lengthsupto12m
Loadsupto100kN  Loadsupto500kN
SECTOR 2
 Mediumtohighcapacitygroundanchors
 Lengths:12mto130m
 Testloadsupto20000kN
SOME SPECIAL
APPLICATIONS
Tunnel subjected to a
maximum hydrostatic head
of 60m
(courtesy PSM)
Burnley Tunnel,
Melbourne,
Australia
Typical cross section through the central section of the tunnel showing
fanned arrays of 46mm diameter monobar anchors with overall lengths
varying between 7 - 10m.
In total some 5200 anchors with working load of 1000kN were
installed over a distance of 2km to resist uplift pressures