Table 1. Standard Laboratory Test Procedures

ERDC TN-DOER-N5

July 2000

Unified Soil Classification System classification.

Specific gravity.

Organic content.

Standard geotechnical laboratory test procedures, such as those of the American Society for Testing

and Materials (ASTM), should be used for each test. Table 1 gives the standard ASTM designation

for the needed tests; it also cross-references the ASTM procedures to those of several other

organizations that have standardized test methods. As discussed in the following paragraphs,

nonstandard laboratory testing must usually be used for shear strength, consolidation, and perme-

ability determinations in these very soft dredged materials.

Table 1

Standard Laboratory Test Procedures

Test Designation

3,4

COE

DoD

Comments

Soil

ASTM

AASHTO

Water content

D 2216

T265

Method 105, 2-VII

Grain size

D 422

T88

2-III, 2-V, 2-VI

Atterberg limits

D 4318

T89

III

Method 103,

T90

2-VIII

Classification

D 2487

III

Specific gravity

D 854

T100

2-IV

Organic content

D 2974

Use Method C

Consolidation5

D 2435

T216

VIII

Permeability6

D 2434

T215

VII

Shear tests

D 2573

Field test

D 4648

Laboratory test

American Association of State Highway and Transportation Officials.

Headquarters, USACE (1986).

Department of Defense (1964).

Department of the Army (1987).

Do not use the ASTM laboratory test for determining consolidation. Instead, use the modified standard

consolidation test and the self-weight test (Headquarters, USACE, 1987; Cargill 1983; Poindexter 1987, 1988).

One value of pemeability must be calculated from the self-weight consolidation test.

Shear Strength Testing. Determination of the shear strength of very soft soils is extremely

difficult. Because of the soft conditions of the materials, they are difficult to sample, transport, and

test in an undisturbed condition. Many of these soils are too soft to stand under their own weight;

thus conventional triaxial testing, unconfined compression testing, and direct shear testing are

impossible or impractical to run. The most commonly used laboratory testing technique for very

soft sediments is the laboratory vane shear device. Although it does not always correlate directly

to field vane testing, it is much more economical and is used extensively in the marine sediment

industry. Because of its extensive use and the large volume of strength data it has generated, the

laboratory vane shear test is well accepted in the marine geotechnical engineering community.