Fuel Tank Stabilization, Cellular Concrete

Tank Stabilization using Cellular Concrete, Petersburg, Virginia

Challenge:

The floors of 20,000 gallon ethanol brewing tanks at a green energy trash processing facility buckled up off of their sloped concrete bases during installation.  

During welding of the tank floor seams, the metal buckled as it cooled.  This caused the metal tank floors to buckle up to 4 inches above their intended elevation.  The tank floors were sloped, and served as the anchoring surface for blending equipment.  The blending equipment needed to be anchored to a solid base.  Since the floor panels buckled up, they bounced significantly and changed elevations due to slight changes in loading, which wasn’t acceptable.

Limits:

Tank stabilization using cellular concrete to fill below the floor of a metal blending tank.The joint between the underlying concrete bases and the tank floors was open around the perimeter, so it had to be sealed to contain cellular concrete during placement, but also only left a 7/8” gap to place material through. 

Due to the flexibility of the floor, non-segregating material was necessary to ensure completely uniform support.  Grouting had to be completed before internal blenders could be installed.  The material also had to have good early strength gain in order to facilitate the completion of the tank construction.

Solution:

Lightweight cellular concrete was chosen for the void filling because it is easily pumped through small orifices, is non-segregating, and offered a 10x safety factor beyond the tank loading.  Non-segregation was very important in this application due to the varying void thickness and the need for very uniform support.  

Result:

CJGeo placed 4.5 cubic yards of lightweight cellular concrete through custom-constructed lie-flat hoses after sealing the tank perimeters with polyurethane foam.  The blenders were welded to the floor of the tanks the day after the tank stabilization by CJGeo and construction continued.

This was the first time that the ready mix supplier had ever supplied a cellular concrete operation, and the first time that the industrial contractor responsible for the repair had used cellular concrete on a project.