Load Controlled Cyclic Triaxial Strength of Soil

D5311/D5311M- 13: Standard Test Method for Load Controlled Cyclic Triaxial Strength of Soil

When designing infrastructure in seismically active regions or areas prone to dynamic loading, understanding a soil's response to cyclic stresses is paramount. ASTM D5311/D5311M-13 provides an essential framework for performing these critical evaluations, offering engineers a proven method to assess soil stability under repeated stress applications.

What is D5311/D5311M- 13?

ASTM D5311/D5311M-13 is an authoritative standard test method developed by ASTM International. It details the procedures for conducting load-controlled cyclic triaxial tests on soil specimens. This comprehensive standard is designed to determine a soil's resistance to cyclic loading, a crucial factor in assessing liquefaction potential and overall soil strength under dynamic conditions.

Scope & Purpose

This standard governs the laboratory testing of saturated soil specimens, whether intact or reconstituted, to evaluate their cyclic strength. It specifically outlines the load-controlled cyclic triaxial technique, focusing on parameters like axial strain development, applied cyclic stress magnitude, pore-water pressure buildup, and effective stress changes. While primarily applicable to cohesionless, free-draining soils, the standard provides guidance for testing other soil types with appropriate considerations. It does not cover the interpretation of results for specific design applications or the broader context of field stress conditions.

Who Must Comply?

• • Primary audience: Geotechnical Engineers, Civil Engineers, Soil Technicians, Materials Scientists, and Research Scientists involved in geotechnical investigations and design.
• • Industries affected: Civil Engineering, Construction, Geotechnical Investigation, Infrastructure Development, and Environmental Engineering.
• • Compliance nature: Voluntary, but widely adopted as an industry-leading practice for critical projects.
• • Enforcement: Typically checked by project owners, regulatory bodies, and peer review processes during design and construction phases.

Key Requirements Overview

• • The standard requires the use of a load-controlled cyclic triaxial apparatus to apply a sinusoidally varying axial load to a confined soil specimen.
• • Professionals must ensure specimens are saturated and consolidated under appropriate effective confining pressures prior to cyclic loading.
• • Key provisions include the continuous monitoring of cyclic axial deformation and excess pore-water pressure development throughout the test.
• • Failure criteria must be clearly defined, often based on achieving a limiting cyclic strain or a 100% pore pressure ratio (indicating potential liquefaction).
• • Meticulous attention to testing details, including specimen preparation and equipment calibration, is essential for obtaining reliable results.

Related Standards & References

ASTM D5311/D5311M-13 is often used in conjunction with other ASTM standards for a complete geotechnical evaluation. These may include:

• • ASTM D653: Terminology Relating to Soil, Rock, and Contained Fluids, for standardized definitions of key terms.
• • ASTM D4767: Test Method for Consolidated Undrained Triaxial Compression Test for Cohesive Soils, for comparison of static and dynamic strength characteristics.
• • ASTM D6026: Practice for Using Significant Digits in Geotechnical Data, to ensure consistency