A couple of weeks ago, I was on one of our projects in Tennessee which, fortunately for us, is a rock job. As luck would have it for us as well, the cut material is below optimum moisture content. We have the best of both worlds for a winter grading project. This, combined with our grading contractor hitting it hard in the recent good weather, translates to success.
Beginning this time of year, the construction process is at the mercy of weather. Winter grading, for example, is more time consuming and labor intensive. Moisture is the enemy, and there are fewer hours of daylight–thus less drying time–with soils above optimum, not to mention the increase in rain and/or snow. A few things we do:
Phase the grading. Grade with a crown 2 feet higher than the proposed subgrade to protect the site from construction equipment, which will have more impact when the soil moisture is higher. At slab construction time, you can trim the damaged layer back, landing at the proper height and avoiding undercutting. This is generally referred to as “safe-ing up the site.”
Direct Traffic. Establishing construction roads can restrict traffic from weaker areas of the site and protect compacted soils.
Fight the Weather. You can place soil over a large area and seal it with a drum roller to protect the base layer from moisture, or use lightweight placement and compaction equipment to “work the soil.”
Cheat, if you have to. Chemical stabilization be used to weatherproof soils.
