Practical Methods
How to Prepare Subgrade for Road Base
Before road base is placed, the subgrade should be accepted for both level and condition. An uneven or weak supporting surface can lead to thickness variation and premature failure above it.
Plan the surface handover
BeforeConfirm formation level and identify unaccepted areas.
Work stageRepair unsuitable support as instructed, trim the accepted material and complete the required compaction preparation.
AfterInspect and accept before spreading base aggregate.
What to verify
Record level and material checks for the same work area.
Use the method as a planning sequence and adapt it to the actual terrain, material and project requirements. Identify the datum and the stopping point before work, then retain checks that show whether the intended correction was achieved.
Scope and limits
Adding more base material is not automatically a remedy for weak subgrade.
Continue the job brief
Include the location, existing condition, intended surface, material, available tractor and proposed dates.