Determine the in-situ undrained shear strength of cohesive soils quickly and reliably in the field. The Field Vane Shear Tester features a robust torsional spring mechanism, drag ring for easy read-out, and three interchangeable vanes to cover a wide range of soil strengths — from very soft to stiff clays. Supplied complete with six 0.5m extension rods for testing at depth.

What Is a Field Vane Shear Test?

The field vane shear test is one of the most reliable and widely used in-situ methods for measuring the undrained shear strength (Su) of soft to firm cohesive soils. By rotating a four-bladed vane into undisturbed soil and measuring the torque required to shear the soil cylinder, the test gives direct, rapid results — without the delays and sample disturbance associated with laboratory testing.

The method is standardised under ASTM D2573 and is routinely used across geotechnical site investigations, earthworks assessment, foundation design, and soft ground construction projects.

Product Overview

The GeoSite Supply Field Vane Shear Tester is a portable, hand-operated instrument designed to determine in-situ undrained shear strength in clays and cohesive soils. Robust, accurate, and simple to operate, it is equally suited to trial pit testing, shallow borehole testing, and top-of-sample measurements on undisturbed tube samples in the field.

The instrument comprises a T-handle body housing a calibrated torsional spring, a drag ring indicator for read-out convenience, and three interchangeable vanes of different sizes. A dummy is supplied for zero calibration, and six 0.5m extension rods allow the vane to be advanced to a maximum depth of 3 metres.

Key Features

• Measures in-situ undrained shear strength of clays and cohesive soils
• Measuring range 0–260 kPa with 5 N·m torque spring
• Three interchangeable vanes (small, medium, large) — all with 2:1 height/diameter ratio per ASTM D2573
• Drag ring for easy peak torque read-out
• Dummy included for zero-point calibration before each test
• Six 0.5m extension rods for testing to 3m depth
• Compact and lightweight — suitable for trial pit work, borehole top and tube sample testing
• Compliant with ASTM D2573

When to Use Each Vane

The correct vane size depends on the expected strength of the soil being tested:

• Large vane (50.8 × 25.4 mm) — use in very soft to soft clays with low expected shear strength
• Medium vane (40 × 20 mm) — use in soft to firm clays
• Small vane (32 × 16 mm) — use in firm to stiff clays where higher torque readings are expected

Typical Applications

• Geotechnical site investigations — trial pit and shallow borehole assessment
• Foundation design and soft ground assessment
• Embankment and earthworks stability studies
• Marine and coastal soil investigations
• Contaminated land and environmental assessments
• Teaching and laboratory demonstration of in-situ testing principles

Standard

ASTM D2573 — Standard Test Method for Field Vane Shear Test in Cohesive Soil

Supplied Complete With

• 1 × Spring torque meter (T-handle body with torsional spring and drag ring)
• 3 × Interchangeable vanes (small, medium, large)
• 6 × Extension rods, 0.5m each, Ø10mm
• 1 × Dummy for zero calibration
• 1 × 8mm spanner
• 1 × 17mm spanner

Technical Specifications

Availability and Dispatch

Availability and lead times vary by product. Some items are held in stock, while others are ordered from our suppliers. Please contact us through the contact option available on this sales channel before ordering if you require confirmation of availability or delivery times.

Why Buy from Geo Site Supply?

• Free standard UK delivery
• Worldwide delivery available
• Secure checkout
• Product suitability and technical support available through this sales channel