Geosynthetics August/September 2020 - 17

Geosynthetics Group team to jointly
brainstorm solutions that may be incorporated to overcome the project challenges and to make the required repairs
that would solve the erosion problems.
This team quickly arrived at a potential
innovative geosynthetic solution that
would meet all the challenges and could
be rapidly executed.
The solution called for an underwater cofferdam to be installed adjacent
to the base of the concrete structures
under which erosion scour was occurring. The cofferdam would be formed
using 65-cubic-yard (50-m3) sand-filled
geotextile bag containers weighing 99
tons (90 tonnes) (Figure 3). The individual geotextile bag units would be flexible enough to conform to the irregular eroded bottom of the canal, yet they
would be massive enough to withstand
the prop wash of the tugs and high velocity of the water flowing out of the canal
locks underneath the Panamax-size ships.
In addition, the geotextile bag structure
would provide a 7-foot (2-m) thick ×
16-foot (5-m) wide erosion control mattress along the base of the entry slab and
on either side of the canal entry dividing
wall. The geotextile bag containers would
be prefilled at an off-site location and
transferred to the Gatun Locks where
a 386-ton (350-tonne) barge-mounted
crane would lift and place them to form a
13-foot (4-m) high × 16-foot (5-m) wide
× 98-foot (30-m) long cofferdam. Once
the cofferdam was constructed, concrete
would be pumped behind the cofferdam
and underneath the entry slab to fill the
eroded void. This two-step process would
be performed during successive scheduled 12-hour maintenance windows.
TenCate had previously developed
and tested the full-scale system of filling, lifting and placing 65 cubic yards
(50 m 3) of sand-filled geotextile bag
containers, which weighed 99 tons (90
tonnes). The bags were fabricated from

FIGURE 4 Filling geotextile bag containers at off-site location

a 1,142-pounds-per-inch (200-kN/m)
woven polypropylene geotextile in a
16-foot (5-m) wide × 16-foot (5-m) long ×
7-foot (2-m) high configuration. The bag
had a top lid that was open for filling with
sand and could be closed and mechanically sealed to permanently contain the
sand. A unique 2,284-pounds-per-inch
(400-kN/m) friction geogrid harness was
designed and full-scale tested to provide
the flexible system of lifting and placing.
The ACP determined that the geotextile bag system provided the required
factors of safety and met its criteria to
repair the Gatun Locks on the Atlantic side
during the 12-hour maintenance window
without disrupting the canal operations.

The operation
The ACP resolved that the off-site
geotextile bag-filling operation would
be conducted at its maintenance dock
facility adjacent to the canal near the
Gaillard Cut, 32 miles (51 km) from the
Gatun Locks (Figure 4). The ACP Titan

The ACP determined
that the geotextile
bag system provided
the required factors
of safety and met
its criteria to repair
the Gatun Locks on
the Atlantic side
during the 12-hour
maintenance window
without disrupting
the canal operations.

www.GeosyntheticsMagazine.com

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Geosynthetics August/September 2020

Table of Contents for the Digital Edition of Geosynthetics August/September 2020

Geosynthetics August/September 2020 - Cover1
Geosynthetics August/September 2020 - Cover2
Geosynthetics August/September 2020 - 1
Geosynthetics August/September 2020 - 2
Geosynthetics August/September 2020 - 3
Geosynthetics August/September 2020 - 4
Geosynthetics August/September 2020 - 5
Geosynthetics August/September 2020 - 6
Geosynthetics August/September 2020 - 7
Geosynthetics August/September 2020 - 8
Geosynthetics August/September 2020 - 9
Geosynthetics August/September 2020 - 10
Geosynthetics August/September 2020 - 11
Geosynthetics August/September 2020 - 12
Geosynthetics August/September 2020 - 13
Geosynthetics August/September 2020 - 14
Geosynthetics August/September 2020 - 15
Geosynthetics August/September 2020 - 16
Geosynthetics August/September 2020 - 17
Geosynthetics August/September 2020 - 18
Geosynthetics August/September 2020 - 19
Geosynthetics August/September 2020 - 20
Geosynthetics August/September 2020 - 21
Geosynthetics August/September 2020 - 22
Geosynthetics August/September 2020 - 23
Geosynthetics August/September 2020 - 24
Geosynthetics August/September 2020 - 25
Geosynthetics August/September 2020 - 26
Geosynthetics August/September 2020 - 27
Geosynthetics August/September 2020 - 28
Geosynthetics August/September 2020 - 29
Geosynthetics August/September 2020 - 30
Geosynthetics August/September 2020 - 31
Geosynthetics August/September 2020 - 32
Geosynthetics August/September 2020 - 33
Geosynthetics August/September 2020 - 34
Geosynthetics August/September 2020 - 35
Geosynthetics August/September 2020 - 36
Geosynthetics August/September 2020 - 37
Geosynthetics August/September 2020 - 38
Geosynthetics August/September 2020 - 39
Geosynthetics August/September 2020 - 40
Geosynthetics August/September 2020 - 41
Geosynthetics August/September 2020 - 42
Geosynthetics August/September 2020 - 43
Geosynthetics August/September 2020 - 44
Geosynthetics August/September 2020 - 45
Geosynthetics August/September 2020 - 46
Geosynthetics August/September 2020 - 47
Geosynthetics August/September 2020 - 48
Geosynthetics August/September 2020 - Cover3
Geosynthetics August/September 2020 - Cover4
https://www.nxtbook.com/ifai/geosynthetics/geosynthetics-december-2021-january-2022
https://www.nxtbook.com/ifai/geosynthetics/geosynthetics-october-november-2021
https://www.nxtbook.com/ifai/geosynthetics/geosynthetics-august-september-2021
https://www.nxtbook.com/ifai/geosynthetics/geosynthetics-june-july-2021
https://www.nxtbook.com/ifai/geosynthetics/geosynthetics-april-may-2021
https://www.nxtbook.com/ifai/geosynthetics/geosynthetics-february-march-2021
https://www.nxtbook.com/ifai/geosynthetics/1220GS
https://www.nxtbook.com/ifai/geosynthetics/1020GS
https://www.nxtbook.com/ifai/geosynthetics/0820GS
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https://www.nxtbook.com/ifai/geosynthetics/0619GS
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https://www.nxtbook.com/ifai/geosynthetics/0219GS
https://www.nxtbook.com/ifai/geosynthetics/1218GS
https://www.nxtbook.com/ifai/geosynthetics/1018GS
https://www.nxtbook.com/ifai/geosynthetics/0818GS
https://www.nxtbook.com/ifai/geosynthetics/0618GS
https://www.nxtbook.com/ifai/geosynthetics/0418GS
https://www.nxtbook.com/ifai/geosynthetics/0218GS
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