Geosynthetics October/November 2023 - 24

Leveraging soil nail technology for MSE retaining wall
Design-build solutions
After multiple site visits and analyses,
GeoStabilization's integrated team of
licensed geologists and geotechnical engineers
moved into the design-build phase.
Design-build solutions are customized
to the varying demands, constraints and
unique characteristics of a given site.
This approach offers many advantages to
owners and contractors, including lower
total project costs and reduced construction
time due to consistent and continual
in-office and on-site collaboration with
the entire owner-driven team of experts.
During the design phase, the team
2a
immediately identified potential challenges
and constraints, and coordinated
logistics to deploy the appropriate construction
crews and equipment. At the
same time, failure modes were being
confirmed in conjunction with repair
methodology to determine the full scope
of work for the project.
Soil nail technology
Knowing there was no desire to vacate
the building or to inconvenience the
residents, GeoStabilization had to find
a solution that would allow for safe construction
within the significant space
constraints while not hindering the construction
of the high-rise condominiums
only 20 feet (6.1 m) away from the northwestern
side of the repair. Due to these
challenges, the existing retaining wall had
to remain in place while the site was stabilized.
Conventional construction methods,
therefore, were not a viable solution.
Because of these factors, GeoStabilization
embraced soil nail technology as the primary
construction method.
The repair involved installing a matrix
of grouted soil nails varying from 15 to 40
feet (4.6 to 12.2 m) long in a pattern along
the many faces of the 610-foot(185.9 m)
long wall. The existing wall retains foundation
material for the building and the
adjacent parking structure, and the wall
repair extends the entire length of the
southwestern face along Longleaf Drive
Northeast in Atlanta. The repair along
the northwestern side within the alleyway
adjacent to the new high-rise was 160
feet (48.8 m) long with approximately 30
feet (9.1 m) of repair needed along the
southeastern side of the property. Once
the soil nails were in place along these
three sides, a steel-reinforced shotcrete
facing was installed.
Soil nails combined with a shotcrete
facing countered the forces associated
with the retained earth wanting to push
out into the surrounding streets. The
primary action of each nail is to develop
a force of friction between the injected
grout around the nail and the surrounding
soil. This friction develops along the
2b
FIGURES 2A-2B Stress cracks in the blocks were observed at various locations and
heights and in a consistent fashion, and visible bulging was evident in the wall.
24
Geosynthetics | October November 2023
length of the nail, and then all nails are
" tied " together through a steel-reinforced
shotcrete face.
Because the rough texture and gray
color of the standard shotcrete face was
Geosynthetics October/November 2023

Table of Contents for the Digital Edition of Geosynthetics October/November 2023
