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7/27/2019 Infographic: Shoring up iconic Washington Monument
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The 555-ft. (169 m) tall monument was renovated from 1998 through 2001. Architect Michael Graves designed the scaffolding.After being damaged during the earthquake of Aug. 23, 2011, it is being repaired again, inside identical scaffolding. The monumentis due to reopen in 2014. Billionaire David Rubenstein matched a $7.5 million allocation by Congress to pay for the work.
The crack shown aboveis typical of manyfractures of panels in thepyramidion, the topmostpart of the monument The scaffolding does not
contact the stones in thepyramidion section of themonument
There are four motorizedworking decks on eachmonument face, with 3 ft.(1 m) of working spaceinside the scaffolding
Scaffolding legs areembedded in concretefoundation pads, setaround monuments plaza,which distribute weight
1 2
3 4
5 6
7 8
Source: National Park Service, The Washington Post, U.S. Geological Survey, Wiss, Janney, Elstner Associates, Inc., John Milner Associates Inc., MCT Photo Service Graphic: Robert Dorrell, Olivier Douliery 2013 MCT
Shoring up iconic Washington Monument
Cracks in panels near top
Crack
Crack
Working up and downan enormous scaffold
Most of the overall damagewas done in the pyramidion,but all four sides suffered
1. Cracks instone, called aspall, near thepyramidioncapstone on thewest side
2. Daylight
shows throughvertical joint justabove the 450ft. (137 m) level
3. Complexspall at site ofearlier repair,northeastcorner
4. New crack,in stone andsealant, on anolder repair job
5. Crack, westside, near top
6. Fracture in tiebeam in theinterior, nearsouth side
7. Daylightthrough anothervertical crack
8. Scaffoldingreaching towardthe top
Damaged stone panelson all sides of monument
Examples ofearthquakedamage
Workers on scaffold at monuments pyramidion
On July 8, the scaffolds lights shine out
Damage was heavier at outer corners of themonument; four methods will be used to make repairs
Anchoring Stone piecessecured with adhesive;anchors drilled intointerior stone
PatchingSpace is cutout aroundspot of amissingpiece ofstone; amatchingpiece is fit
into space,attached withsteel rodsand adhesive
SealingAdhesiveinjected intocracks;limestonedust addedto surface tohide thecrack
Repointing Damaged mortar removed, replaced
Bedrock an average depthof 80 ft. (18.3 m) belowbottom of foundation
Types of repairs being done to side panels
Granite
Granite
Stone
Stone
Scaffolding set upontemporary concrete pads
Loam, fill, clay
Loam, fill, clay
Sand, clay mix
Sand, clay mix
Sand, gravel, clay
Sand, gravel, clay
Blue clay
Blue clay
Foundationconcrete, gneiss rubble
Foundationconcrete, gneiss rubble
Anchor brackets willconnect shifted externalmarble panels to interiormarble rib supports,adding stability
Installing anchors
Braces at cornersand center ofmonument sides,joined by steel cables,secure scaffolding
Brace pads aremade of wood, coatedwith plastic foam toprevent scratchingstone slabs
Scaffolding anchored
by corner braces
100
200
300
400
500
Northface
Westface
Southface
Eastface
Damaged panels
555 ft.(169 m)
Anchorbrackets
Anchorbrackets
Internalstoneribs
InternalstoneribsExternal slab
External slab
Scaffolding
Scaffolding
Crushed stone
Crushed stone
Concrete pad
Concrete pad
Scaffolding
Scaffolding
Work deck
Work deck
Tensioner
Tensioner
Cornerbrace
Cornerbrace
Pad
Pad
Scaffolding
Scaffolding
Cable
Cable
Platform
Platform
Motor
Motor
Scaffolding
Scaffolding
Pyramidion
Pyramidion