Abstract: The large circular underground supporting structure is a good form of structure which combines the system function of deep excavations as wells as takes the advantage of the arch effect. This structure has the advantage of simplicity, wide applications and fast construction. Currently, the major concern in the structural design is focused on the structural stability. The arch effect is neglected in the conventional vertical section analysis. Therefore, the circumferential stress might be underestimated as a result of the conventional analysis. This paper estimates the tangential and radial stress of the circular supporting structures based on the classical solution of a linearly load elastic tube. It is concluded that the circumferential stress of the circular supporting structure is approximately increased with the radius of the structure. The tangential stress of the supporting structure should be examined for a safe design of the deep excavation supporting structure.

Key words: Large Circular Supporting Structure, Diaphram Wall, Elastic Theory, Circumferential Stress, Radial Stress