Why Gravix?
- Designed for DOT applications
- Gravix® is accepted by 42 DOT’s across the United States and expanding rapidly
- Gravix is available with stem lengths up to 40 feet
- Cost reduction and time savings due to smaller (typically 3 to 4 man) crews/100% precast
- Onsite soils can often be utilized with the Gravix system (AASHTO Prefabricated Modular Design Methodology)
- Gravix Slot Construction – tighter sites, existing utilities & obstructions
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Gravix wall is the best and quickest option for the earth retaining world. It is cost effective.
Siddharth Balar -CMES Inc.
THE DESIGN
The Gravix wall units vary in stem depth dependent upon the wall height, as well as surcharge. A standard unit is 32 SF of face area (8’ x 4’). A typical wall section has the longest units at the bottom and get shorter as they are stacked vertically. Also, at the top of a wall, to follow grade, the casting mold is placed on a tilt table to allow the top of the unit to be cast on a slope. The sloping top edge of the units allows all of the unique geometry top units to be precast and customized for each project. The angled precasting also produces a leveling unit to be used directly below traffic barrier units to allow the uniform traffic barrier unit to parallel roadway grade. The precaster can then provide a complete retaining wall package to the highway contractor. Gravix, providing large precast units and a complete retaining wall system, allows the highway contractor to use less labor, common equipment and achieve higher installation rates, saving time and money.
All of the units incorporate a triangular section in the stem perpendicular to the face that allows the weight of the backfill to bear on the units below, thus transferring downward pressure, which results in a stabilizing effect. In combination, the units create a coherent gravity mass designed to resist overturning, sliding and bearing failure. The design methodology follows the well-accepted AASHTO guidelines of a conventional Prefabricated Modular Retaining Wall.
MASH TL-4 TRAFFIC BARRIER
Gravix® entered the highway market after becoming the first all 100% precast traffic barrier to pass the MASH TL-4 impact test. In 2013, a test Gravix® wall was constructed at the Texas Transportation Research Institute (TTI) testing and proving grounds in College Station, Texas. The test wall and barrier successfully passed the MASH TL-4 test and received its Letter of Eligibility from the FHWA.
- Integrated moment slab
- 42” single slope
- Can be placed on top of Gravix as well as MSE panel walls
TOP AND LEVELING UNIT
- Custom top units
- Leveling units to meet roadway grade
- No cap or coping required
To allow the top of the retaining wall to follow grade, angled top units are cast using molds on a tilt table. For Gravix retaining walls that require a traffic barrier, a leveling unit is installed directly below the Gravix traffic barrier unit, also cast on a tilt table, to allow the Gravix traffic barrier to follow roadway grade.
SLOT CONSTRUCTION
- Eliminate temporary shoring
- Provide a safer sloped back-cut
- Reduce infill stone volume
Resources
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