Repair and strengthening of masonry arches. Network Rail’s Experiences Is strengthening necessary? Brian Bell, Network Rail
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Presentation otline ! "rch #ridges #ridges ! $eterioration and repair ! %trengthening & 'onsiderations & (echni)es
! *rther reading ! " new de+elopment de+elopment
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Presentation otline ! "rch #ridges #ridges ! $eterioration and repair ! %trengthening & 'onsiderations & (echni)es
! *rther reading ! " new de+elopment de+elopment
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Each arch #ridge is ni)e %mall
daring designs
main spans -5’ /63m2, rise 57’ /8m2
high --’ /approx 01m2 main span, -03’ /approx 44m2 a#o+e watercorse
long
long
…
sometimes do fnny 9o#s
and can #e pictres)e:
! (hey tend to +ery long lasting ! Bt they do sffer from wear and tear
Natral deterioration
$amage
Repair methods ; repointing
Pointing mortar mst #e weaker than masonry in arch
Repair methods ; groting
Repair methods & patch repair (ry to match physical properties of the new nits with those of the existing nits
Repair methods & patch repair (ry to match physical properties of the new nits with those of the existing nits
Ring separation
Repair method ; throgh ring stitching
Pier
Pier
Pier
Repair methods ; nderpinning
%pandrel mo+ement
Repair methods & pattress plates
Parapet damage
Repair methods & repair<pgrade
Inade)ate capacity
%trengthening considerations ! 'onsider careflly #efore specifying & 'an fondations take increased loading? & "re load paths within arch altered? & =ill arch #e stiffer afterwards? & "re sppliers’ p#lished claims relia#le? & =ill arch #e naccepta#ly weakened as part of installation process? 26
>a#oratory test method
%trengthening ; concrete saddle
%addling +ideo
%trengthening ; prefa#ricated liners
%trengthening & near srface reinforcement
%trengthening & throgh arch reinforcement
ther methods ! Relie+ing sla# ! %prayed concrete ! (hickening srface
Recommended reading
'IRI" report '040 a+aila#le for free download or prchase from www.ciria.org
(he %staina#le Bridges Report ! 'hapter 7.4 descri#es repair and strengthening techni)es for arch #ridges ! "ppendix ' looks at strengthening in more detail www.sstaina#le#ridges.net @pro9ect reportsA
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