1Joseph E. Bowles, Foundation Analysis and Design, Third edition, McGraw-Hill Book Company, 1982:622 -623.
2Kulhawy, F. H. , Kozera, D. W, and Withiam, J. L., Uplift testing of model drilled shafts in sand, J. Geotech. Engrg. Div. , ASCE, 105 (1), 1979:31 -47.
3Nak Kyung Kim, Performance of Tension and Compression Anchors in Weathered Soil, Journal of Geotechnical and Geoenvironmental Engineering, ASCE, 2003 (12) : 1138 -1150.
