Astm D338518 Pdf !full! -

Usually 24 inches (600 mm) in diameter. It acts as a buffer to limit the lateral spread of water, ensuring that water from the inner ring moves in a one-dimensional, vertical flow for more accurate results. Test Procedure and Methodology

A critical note in the standard (section 5.4) states that tests performed at the same site are likely to produce varying results due to many factors (e.g., soil structure, layering, temperature). Therefore, the results of this test are primarily intended for comparative analysis under similar conditions rather than for deriving an absolute permeability value.

ASTM D3385-18, officially titled “Standard Test Method for Infiltration Rate of Soils in Field Using Double-Ring Infiltrometers,” serves as the industry benchmark for this measurement. By utilizing a concentric ring apparatus, the method aims to minimize lateral flow divergence, thereby providing a more accurate representation of the vertical hydraulic conductivity of the soil. This paper dissects the standard, offering guidance on its practical application and theoretical basis.

Tests cannot be accurately performed on frozen or heavily saturated soils from recent heavy rainfall. astm d338518 pdf

ASTM D3385-18 is the standard test method established by ASTM International for determining the infiltration rate of soils using a double-ring infiltrometer. The "18" denotes the year of its last major revision or reapproval.

V=ΔQA×Δtcap V equals the fraction with numerator cap delta cap Q and denominator cap A cross delta t end-fraction = Infiltration velocity (typically expressed in mm/minmm/min

Place the driving cap on the outer ring and center it. Place the wood block on top of the driving cap to absorb impact. Usually 24 inches (600 mm) in diameter

Drive the outer ring into the soil to a depth of at least 150 mm (6 in.). It is vital to minimize soil disturbance and prevent tilting.

A single-ring infiltrometer often overestimates infiltration rates because water diverges laterally (sideways) once it passes the bottom edge of the ring. The double-ring design solves this issue:

: Center the inner ring inside the outer ring and drive it to a similar depth. Vertical Alignment Therefore, the results of this test are primarily

While ASTM D3385-18 provides a valuable tool for evaluating geotextiles, there are challenges and limitations, including variability in testing results and the influence of test conditions on the measured pore size distribution. Additionally, field performance can sometimes differ from laboratory results due to installation conditions, soil properties, and long-term degradation.

ASTM D3385-18 outlines the standard field procedure for measuring soil infiltration rates using a double-ring infiltrometer to manage water, design septic systems, and evaluate groundwater recharge. The test requires driving 300 mm and 600 mm diameter rings into the soil, followed by a one-hour presoaking period, before measuring the volume of water required to maintain a constant head. For a complete overview of the procedure, refer to the document at my.civil.utah.edu .

The double-ring infiltrometer solves this problem by using two concentric cylinders:

Infiltration Rate of Soils in Field Using Double-Ring Infiltrometer1