Abstract: Testing methods that evaluating in the composite foundations are very important to ensure the quality control in ground improvement projects. The conventional quality control measure is the evaluating of the bearing capacity of composite foundations. In recent years, more and more testing measures and more and more quality control criteria have been proposed and applied in the practical projects. This paper presents two ground improvement projects that using plain concrete columns. Different quality evaluation criteria, such as, bearing capacity of composite soil and single columns, the strength of concrete column, the integrity of plain concrete column and characterization of soil among columns, are introduced and evaluated with the objective of evaluating the performance of composite grounds using testing data.

Key words: low strain integrity tests, concrete coring test, static loading tests, plain concrete columns, composite foundations