A Home Depot store in Holly Springs, Georgia had to be suddenly evacuated and closed when a large section of a Cast-In-Place (CIP) retaining wall collapsed behind the store. The event also took out the store’s back-up generator, part of their storm water system and a natural gas line. It was later determined that a buildup of hydrostatic pressure behind the wall caused by a leaking water supply line was the primary cause of the failure.
Needless to say, quick action was needed to sort out the mess, secure the site, get the store safely re-opened and come up with a plan to get this wall repaired and functioning properly.
A specialized team comprised of geotechnical engineers and construction companies came together to develop a remediation plan that included a 160' section of our Vist-A-Wall MSE Structural Wall System and significant soil nail reinforcements added to the remaining portions of the original CIP wall. With our constructed wire wall solution and open-graded, select backfill, any future concerns relating to hydrostatic pressures are minimized.
One of our more complex installations to date
Once the area was cleared of the failed CIP wall, the exposed embankment behind the collapse was shored up with a soil nail and shotcrete face tie-back system. The soil nail wall was designed and constructed by Hayward Baker to allow access to the face while protecting the Home Depot store from loss of foundation support. It is directly behind our MSE wall and will be in service for the life of the combined structure.
The remaining portions of the CIP wall were shored and strengthened with supplementary grouted tie-back anchors, also designed and installed by Hayward Baker.
Building our MSE Wire Wall in a confined, narrow space in front of the shored embankment, between the remaining CIP walls and with limited access was challenging enough. Accommodating a storm water system, a gas line and numerous guardrail post foundations, made this one of our more complex and unusual designs. However, the most challenging factor was the intermittent movements of the remaining CIP wall while it was being stabilized.
In collaboration with our project partners, our Engineering and Sales personnel came up with a solution that successfully met all requirements. Time was well spent reviewing the FWHA publication Shored Mechanically Stabilized Earth (SMSE) Wall Systems Design Guidelines for the basis of the design for this soil-nail-shored and MSE combination wall.
Our Wire Mat soil reinforcement system was best suited to this narrow site. Flowable fill was incorporated into a portion of the areas to optimize stability in the most confined areas where our MSE wall is immediately adjacent to the remaining CIP wall. The backfill placement had to be conducted from in front of the wall and then from above the wall once it reached a certain height.
Project at a glance:
Name: Home Depot MSE Wall
Location: Holly Springs, Georgia
Owner: Home Depot
Wall Engineer: The Collin Group, Ltd
Wall Subcontractor: Synergy Earth Systems
General Contractor: Hayward Baker
Product: Vist-A-Wall MSE Structural Wall System (Wire Wall)
Application: Remediation to replace portion of failed Cast-in-Place wall
Dimensions: Length 160', Height 36-38'
Installation Time: Two to three months
Related Media Coverage of Wall Collapse
Retaining Wall Collapses Behind Home Depot »