Shear Strength of Coarse-Grained Soil: Effects of Scaling Methods and Moisture Content with In Situ Comparison
Source abstract
Abstract
Coarse-grained soil (CGS) is a vital geotechnical material extensively used in engineering projects. Scale effects pose challenges to accurately assessing its shear strength, and the influences of scaling methods and moisture content remain underexplored. This study investigates the effects of maximum particle size (dmax), scaling techniques, and moisture content on the shear strength of CGS through large-scale direct shear tests and in situ direct shear tests. CGS samples from the Jilangtan platform in Qinghai Province, originally with a dmax of 60 mm, were scaled to 30 mm using the Equivalent Substitution Method (ESM) and Similar Gradation Method (SGM). Tests were conducted at moisture contents of 0.91% (air-dried), 2.45% (natural), and 7.66% (saturated). Results show that ESM consistently yields higher shear strength than SGM across all moisture levels. Scale effects are minimal under air-dried conditions but become pronounced at higher moisture contents. While all large-scale laboratory test results deviate somewhat from in situ findings, shear strength parameters derived from SGM align more closely with field observations.
Source: crossref · Quality: baseline
Research context
OpenAlex topics: Geotechnical Engineering and Soil Mechanics · Soil and Unsaturated Flow · Geotechnical Engineering and Soil Stabilization
SciVX discovery tags are terminology-based. OpenAlex topics are source-provided classifications.
Affiliations
School of Geology Engineering and Geometrics, Chang’an University, Xi’an 710054, China
Northwest Engineering Corporation Limited, Xi’an 710065, China
School of Water Conservancy and Hydroelectric Power, Hebei University of Engineering, Handan 056038, China
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