Murray Engineers, Inc.

Laboratory Analysis

The physical properties of soil and rock are a critical component of comprehensive geotechnical design. Our laboratory conducts testing on soil and rock materials recovered during surface and subsurface exploration to determine engineering properties used in project design and construction, such as soil and rock strength and stability characteristics, behavior during seismic events, and expansion potential.

ASTM D2216: DETERMINATION OF MOISTURE CONTENT OF SOIL AND ROCK.
Moisture content can provide a useful method of classifying cohesive soils and of assessing their engineering properties. Moisture content of soils may also elucidate design requirements for subsurface drainage and basement waterproofing.

ASTM D422: PARTICLE SIZE ANALYSIS OF SOILS.
Grain size analysis or particle size distribution utilizes sieves for segregation of coarse-grained material (i.e. gravels and sands), and hydrometers and sedimentation cylinders for fine grained material (i.e. silts and clays). The objective of particle size analysis is to determine relative proportions of each size range. Particle size is an important factor in determination of a soil's engineering properties for liquefaction potential analysis.

ASTM D4318: STANDARD TEST METHOD FOR LIQUID LIMIT, PLASTIC LIMIT, AND PLASTICITY INDEX OF SOILS.
The objectives of "Atterberg Limits" tests are to determine the range of water content at which the soil exhibits plastic behavior, which in turn allows estimation of expansion and settlement characteristics.

ASTM D1140: AMOUNT OF MATERIAL IN SOILS FINER THAN NO.200 SIEVE (75um).
This method determines the amount of silt and clay particles in a soil by a wet sieve procedure. The amount of silt and clay in a material is important to soil and rock classification and in determination of a soil's engineering properties.

ASTM D2487: CLASSICFICATION OF SOIL FOR ENGINEERING PURPOSES.
This method is part of the Unified Soil Classification System. This method classifies natural soil including: gravels, sands, silts, clays, organic silts and clays, and peat, and is based on the particle size distribution from particle size analysis, the percentage of organic matter for fine grain soils (silts and clays), and the liquid limit and plasticity index from the Atterberg test.

ASTM D2937: IN-PLACE DENSITY OR BULK DENSITY.
In-place density is determined by the drive-cylinder method, which collects an undisturbed soil sample. The density is expressed by mass per unit volume. Modifications of this method can be used to determine bulk density and dry bulk density.

ASTM D1557: MODIFIED PROCTOR COMPACTION TEST.
Compacting a soil at a known water content into a mold of specific dimensions using a specific amount of compaction energy provides the relationship between dry density and moisture content for a given degree of compaction effort. This test establishes a baseline maximum dry density and optimum water content for onsite soils and/or offsite materials (i.e., aggregate baserock) used as engineered fill in areas of slabs-on-grade, retaining wall and trench backfill, slope reconstruction, and engineered fill slopes.

Murray Engineers Inc. provides geotechnical services in the San Francisco Bay Area including: San Francisco County (San Francisco), San Mateo County (Atherton, Belmont, Brisbane, Burlingame, Colma, Daly City, East Palo Alto, Foster City, Half Moon Bay, Hillsborough, Menlo Park, Millbrae, Pacifica, Portola Valley, Redwood City, San Bruno, San Carlos, San Mateo, South San Francisco, Woodside), Santa Clara County (Campbell, Cupertino, Gilroy, Los Altos, Los Altos Hills, Los Gatos, Milpitas, Monte Sereno, Morgan Hill, Mountain View, Palo Alto, San Jose, Santa Clara, Saratoga, Sunnyvale), and Santa Cruz County (Santa Cruz, Capitola, Santa Cruz, Scotts Valley, Watsonville) Copyright 2012 Murray Engineers, Inc.