Date of Award
Master of Engineering Science
Civil and Environmental Engineering
Dr. Timothy A. Newson
Dr. John R. de Bruyn
Two dimensional plane strain finite element analysis has been conducted to simulate the pullout behavior of vertical anchors of different shapes when embedded in clay. These shapes include plate anchors, anchors with irregular base shapes, and plate anchors with rectangular openings. For the first two types, the effects on the pullout behavior of embedment depth, overburden pressure, soil-anchor interface strength, anchor thickness, base shape and size, rate of clay strength increase, anchor and load inclination, point of load application and soil disturbance due to anchor installation were all studied. The anchor pullout capacity is shown to be strongly affected by embedment depth, overburden pressure, load inclination angle, rate of clay shear strength increase per depth and soil-anchor interface strength. Similarly, disturbed clay strengths adjacent to the anchor following installation were found to cause a significant reduction in the anchor capacity. The effect of other parameters, such as the anchor thickness and the load application point, were found to be less significant. Among the studied base shapes, the triangular based anchors were found to have the greatest vertical pullout resistance, while the lateral pullout was not significantly improved for any of the studied shapes. This form of anchor was also shown to be the most efficient shape in terms of cross-sectional steel area compared to the pullout capacity. Normal and inclined load vertical and horizontal plate anchors with rectangular openings were studied at different embedment depths for no-breakaway and immediate breakaway conditions. For this anchor type, the embedment depth showed a significant effect on the efficiency for fully bonded conditions, but only a negligible effect for immediate breakaway conditions. The results suggest the feasibility of this anchor type as an alternative to regular plate anchors, especially for shallow offshore conditions, where limitations on cranage capacity exist.
Fahmy, Ahmed M., "NUMERICAL INVESTIGATION OF THE UNDRAINED PULLOUT CAPACITY OF ANCHORS EMBEDDED IN CLAY" (2011). Digitized Theses. 3480.