Soil Compaction Testing in San Antonio, TX

What Is Soil Compaction Testing?

Compaction testing measures how densely soil or fill material has been compacted in the field and compares that measurement to a laboratory standard. The goal is to confirm that fill, road base, trench backfill, or structural embankment meets the density the project specifications require.

When compaction falls short of the required standard, problems follow. Pavement fails early, structures built on fill settle unevenly, trenches sink, and embankments shift. Our team catches those problems before they become expensive to fix.

Our geotechnical engineering services in San Antonio include soil compaction testing throughout San Antonio, TX and the surrounding area for projects ranging from residential lot fills to large commercial and infrastructure jobs across Bexar, Comal, and Guadalupe County. for projects ranging from residential lot fills to large commercial and infrastructure jobs.

Why Work With San Antonio GeoTech for Compaction Testing

Results on the Spot

Our field technicians provide compaction test results on-site. If a test does not pass, your contractor knows right then and can re-compact before the project moves forward.

Trained Technicians Following Standard Procedures

Our compaction testing technicians follow ASTM and TxDOT testing standards and maintain detailed field records for every test performed.

We Schedule Around Your Project

Compaction testing has to happen when your contractor is ready. We schedule our technicians around your grading, paving, and construction timeline so testing does not hold up the job.

When Is Compaction Testing Needed?

During Fill Placement and Site Grading

Every lift of fill placed on a construction site should be tested before the next lift goes down. Testing through the full depth of the fill confirms density is being achieved consistently, not just at the surface.

Before Paving Roads, Parking Lots, and Driveways

The base course under pavement has to be compacted to the right density before asphalt or concrete goes down. Under-compacted base is the most common reason pavement fails ahead of schedule. Catching it before paving costs far less than digging it up afterward.

After Utility Trench Backfill

Water lines, sewer lines, gas lines, and conduit trenches need to be properly backfilled and compacted. Inadequate trench compaction leads to ground settlement above the trench. It is common and preventable.

Under Slabs and Foundations

Fill placed beneath concrete slabs and building foundations has to be at the right density before concrete is poured. Our testing confirms compliance before that step.

How Our Compaction Testing Process Works

Step 1: Proctor Test in the Lab

Before field testing begins, a Proctor compaction test is run on a sample of the fill material in the laboratory. This determines the maximum dry density and optimum moisture content for that specific material. That lab result becomes the standard our field measurements are compared against.

Step 2: Field Density Testing

Our technician visits the site and performs field density testing at the required test locations. Results are available immediately on-site.

Step 3: Relative Compaction Result

The field measurement is divided by the laboratory maximum to get the relative compaction percentage. Most project specifications require 95 percent relative compaction for structural fills and road bases.

Step 4: Pass, Fail, and Documentation

If it passes, construction moves forward. If it fails, the material gets re-compacted and our technician retests. Every result is documented in a field report.

Types of Compaction Testing We Perform

Field Density Testing

Our standard method for verifying compaction on construction sites. Results are available on-site immediately after testing.

Standard Proctor Test (ASTM D698)

The laboratory compaction standard used for most general fill and subgrade applications.

Modified Proctor Test (ASTM D1557)

The higher-energy lab standard used for road bases, structural fills, and projects with stricter density requirements.

Frequently Asked Questions About Compaction Testing in San Antonio

How much does compaction testing cost in San Antonio?

Pricing depends on the number of test locations, site conditions, and overall project scope. Contact us for a quote based on your specific project.

How many compaction tests do I need?

The number depends on your project specifications and the engineer of record’s requirements. Your spec documents define required testing frequency. We can help clarify what your project needs.

What does 95 percent compaction mean?

It means the in-place density of the compacted fill is at least 95 percent of the maximum dry density determined in our laboratory Proctor test. This is the most common compaction requirement for structural fills and road bases in the San Antonio area.