Subgrade — Finished-Purpose Link
Define the finished purpose, reference levels, underlying material condition and the evidence required by the receiving operation. Geometry alone does not establish structural or agronomic performance.
This reference assembles relevant extracts from the guide library. It is general project planning, not a local project report, verified specification or translated technical publication.
Uneven Subgrade
Uneven subgrade can create variable thickness in every layer above it. Correcting the surface is useful only if the underlying support is acceptable.
Before moving material
Identify soft areas and compare formation levels with design.
Receiving operation and checks
Complete compaction and specified acceptance checks. Check levels before base material conceals the subgrade.
A scraper does not replace proof testing or project-specific investigation.
Read the complete Uneven Subgrade guideHow 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.
Before moving material
Confirm formation level and identify unaccepted areas.
Receiving operation and checks
Inspect and accept before spreading base aggregate. Record level and material checks for the same work area.
Adding more base material is not automatically a remedy for weak subgrade.
Read the complete How to Prepare Subgrade for Road Base guideSubgrade Preparation
Subgrade preparation creates the surface that supports the next pavement or structural layer. The visible level and the condition of the material both matter.
Before moving material
Remove unsuitable material according to the project instructions and establish the formation reference.
Receiving operation and checks
Prepare for the specified compaction and acceptance process. Check levels, moisture and soft areas before the next layer is placed.
A geometric check cannot replace material testing.
Read the complete Subgrade Preparation guideRecord the job inputs
Use this checklist to turn the scenario into a specific brief. Retain the design revision and agree who accepts each completed layer.
Checklist ticks apply only while this page is open. Include the completed brief in your project records.
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