1. The test results reflect only the character of the soil located within the depth Iess than twice the width of bearing plate (corresponding to a pressure bulb of one-tenth of the loading intensity at the test plate). Since the foundations are generally larger, the settlement and resistance against shear failure will depend on the properties of a much thicker stratum.
2. It is essentially a short duration test, and hence the test does not give the ultimate settlement, particularly in the case of cohesive soils.
3. Another limitation is the effect of the size of foundation. For clayey soils the ultimate pressure for a large foundation is the same as that for the test plale. But in dense sandy soils, the bearing capacity increases with the size of the foundation, and the tests on smaller size bearing plates tend to give conservative values.
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