ASTM D3385-18 establishes a standard field method using a double-ring infiltrometer to determine the water infiltration rate of soils. It is designed for assessing water movement in unsaturated, fine-grained soils for environmental and engineering projects, excluding highly pervious, impervious, or frozen materials. The full technical specification is available through ASTM International or authorized distributors. The University of Utah
The standard provides a rigorous procedure for measuring the infiltration rate of soils in the field using a double-ring infiltrometer. This method is essential for civil engineers, hydrologists, and environmental scientists to determine how quickly water penetrates a site's soil—a critical factor for designing drainage systems, septic fields, and irrigation networks. Overview of ASTM D3385-18
For designing stormwater management systems, such as bioretention cells or permeable pavement sub-bases, accurate infiltration rates dictate the required footprint and capacity of the drainage infrastructure. How to Access the ASTM D3385-18 Standard astm d338518 pdf
Generally around 500 mm (20 inches) tall to allow for proper soil insertion and a sufficient water head. 2. Water Supply and Measurement Systems
Guide to ASTM D3385-18: Standard Test Method for Infiltration Rate of Soils in Field Using Double-Ring Infiltrometer ASTM D3385-18 establishes a standard field method using
The standard is particularly applicable to relatively uniform fine-grained soils, with an absence of very plastic (fat) clays and gravel-size particles, and with moderate to low resistance to ring penetration.
ASTM standards are continuously reviewed, updated, and reapproved to reflect modern engineering practices. The "-18" in the designation means that the current active version was last substantively reviewed or updated in 2018. The University of Utah The standard provides a
Clear loose debris, vegetation, and rocks from the surface. Avoid scraping or compacting the target test zone. Step 2: Driving the Rings Center the inner ring inside the outer ring.
Continue the test until a steady-state infiltration rate is achieved—typically requiring 4 to 6 hours or until consecutive readings yield identical infiltration velocities. Data Analysis and Calculation The incremental infiltration velocity ( ) is calculated using the following formula:
acts as a buffer. The water infiltrating from the outer ring creates a saturated "curtain" or boundary around the inner ring.