266371460

WST

ht/0.2 m

not temporary. If it is possible to penetrate the stiff layer the test shall be continued.

Sometimes the weight penetrometer test is followed by percussion boring to deeper levels, e.g. in order to determine the depth to which point-bearing piles need to be driven.

Notę 5 • Clause . 1.1.

In soft soils when the penetration resistance is less than 1 kN a dynamometer can be used instead of the weights. In this case the recorded load shall be related to the closest standard loads and shall be recorded in a similar manner.

WST    WEIGHT SOUNDING TEST

ht/0.2m    NUMBER OF HALFTURNS PER    0.2m OF

PENETRATION

Pt    DRY CRUST OF CLAY

fb(Sp g 60) PREBORING TO THIS LEVEL WITH 80mm

DIAM AUGER

FIGURES TO THE RIGHT IN THE DIAGRAM INDICATE LOADS APPLIED IN kN

Fig. 3 An example of the presentation of test results from weight sounding test (WST).

6. EXPLANATORY NOTES Notę 1. Clause 2.2.1.

The rods and couplings should be madę of high tensile Steel.

Notę 2. Clause 3*2.3.

Differences between manually and mechan-ically performed tests sometimes occur.

Where this may be the case, for example when estimating the relative density of loose cohesionless soils, comparisons between manually and mechanically performed tests must be madę.

Notę 3* Clause 3.3*1*

In cases where the skin friction resistance along the upper parts of the rod can sig-nificantly influence the results, a com-parison should be madę with a test in a prebored hole. Preboring is normally required through a dry crust or through a fili. When the difference in penetration resistance is large between the two tests, preboring is necessary for all tests within the area. The preboring shall be madę using an auger with a minimum diameter of 50 mm. To estimate the thickness of the dry crust the sounding test is performed directly from the ground sur-face.

Notę A. Clause 3*3*2.

A penetration test to "firm bottom" shall be terminated by striking the rod with a hammer or by dropping some of the weights onto the clamp in order to check that the refusal is

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