This paper proposes a novel model that can predict the displacement of suction caisson anchors under monotonic and cyclic loading. Failure is assumed to occur when the accumulative monotonic and cyclic displacement along the load attachment point is over 60% of the diameter of the anchor. The anchors will go through lateral failure when the accumulative monotonic and cyclic displacement along the loading direction at the load attachment point is over 30% of the diameter. Hence, it is important to predict this displacement and therefore determine the expected failure of the anchor. However, it is difficult to predict displacement using the modern software without knowing the material properties of the soil and piles. Hence a new model that relies only on the normalized static load (Fa/Ff), normalized cyclic load (Fcy/Ff ), loading angle (Θ), and the number of cycles (N) is proposed. The inputs for training of the proposed model are (Fa/Ff), (Fcy/Ff), (Θ), (α) and (N). The output of the model will be the displacement normalized by the diameter of the anchor. To generalize the trained model, unused sets of data are used to validate the model. Furthermore, a comparative study is performed to evaluate the effectiveness of the proposed model. It is shown from extensive simulation that the model can accurately predict the normalized displacement of suction caisson anchors.

This paper proposes a novel model that can predict the displacement of suction caisson anchors under monotonic and cyclic loading. Failure is assumed to occur when the accumulative monotonic and cyclic displacement along the load attachment point is over 60% of the diameter of the anchor. The anchors will go through lateral failure when the accumulative monotonic and cyclic displacement along the loading direction at the load attachment point is over 30% of the diameter. Hence, it is important to predict this displacement and therefore determine the expected failure of the anchor. However, it is difficult to predict displacement using the modern software without knowing the material properties of the soil and piles. Hence a new model that relies only on the normalized static load (Fa/Ff), normalized cyclic load (Fcy/Ff ), loading angle (Θ), and the number of cycles (N) is proposed. The inputs for training of the proposed model are (Fa/Ff), (Fcy/Ff), (Θ), (α) and (N). The output of the model will be the displacement normalized by the diameter of the anchor. To generalize the trained model, unused sets of data are used to validate the model. Furthermore, a comparative study is performed to evaluate the effectiveness of the proposed model. It is shown from extensive simulation that the model can accurately predict the normalized displacement of suction caisson anchors.

The purpose of this thesis is to describe the three-dimensional velocity flow field measurements in the vicinity of the inlet mouth of a cutterhead suction dredge. Using acoustic Doppler velocimeters (ADVs), an accurate visualization of the velocity flow field was used to determine the region of influence around the cutterhead. Similitude is used in the experimental study to determine the correlation between the velocity flow field and other dredge parameters such as suction intake diameter without the cutterhead and with a rotating cutterhead. This is useful to the dredging community for two reasons: first, knowing the region of influence around the cutterhead helps the dredger achieve higher production by using a more efficient cutting depth and second, achieving similitude with the velocity flow field allows for more accurate model testing in the future. In order to help understand the more complex flow field around the cutterhead created by the cutting process, scenarios involving three different suction flow rates, three cutterhead rotation speeds, and two swing speeds, were investigated. Prior studies of the flow field around the cutterhead provided a means to predict the velocity at the cutterhead intake. The flow field studies herein provide an extension into three dimensions as well as a verification of the previous results. The highest velocities were found to occur nearest the cutterhead, specifically in the lower hemisphere of the cutterhead where the suction intake is located. The magnitude of these values greatly decreased with increasing distance from the cutterhead. In addition, the flow rate is shown to directly correlate to the velocity around the cutterhead. It was found that the region of influence was nearly symmetrical around the cutterhead, but the shape could more accurately be described as an ellipsoid. The volumes of the regions of influence ranged from 10 ft^3 (0.283 m^3) to 80 ft^3 (2.27 m^3) for the model dredge and from 2,250 ft^3 (63.70 m^3) to 17,000 ft^3 (481.40 m^3).

The hydraulic-mechanical behaviour of swelling clay is examined in this thesis. The study includes laboratory testing and numerical modeling which considers the influence of boundary conditions on the hydraulic-mechanical behaviour of a compacted unsaturated swelling clay soil. The laboratory testing component of this research consists of three (3) series of tests using a newly modified triaxial apparatus on which mechanical and hydraulic boundary conditions are altered during liquid infiltration. Mechanical boundary conditions range from constant volume to constant mean stress and also include constant stiffness which is a spring type boundary consisting of both volume expansion and mean stress increase. Hydraulic boundary conditions include drained and undrained flow into triaxial specimens. The numerical modeling component of this research includes the creation of a new capillary tube model for swelling clay materials and incorporates dynamic changes to the cross-sectional area for flow. Laboratory results are modeled using the capillary tube model, an empirical hydraulic model, D’Arcy’s Law, and in an elastic-plastic context for unsaturated soil. Results of the laboratory and numerical modeling components show that boundary conditions dominate the hydraulic-mechanical behaviour of unsaturated swelling clay soil during liquid infiltration. In particular, a mechanism is shown to explain how hydraulic conductivity of a swelling soil can decrease with increasing water content at constant void ratio. Finally hydraulic and mechanical behaviour cannot be considered separately in swelling materials due to the intimate relationship in their response. / October 2006

The hydraulic-mechanical behaviour of swelling clay is examined in this thesis. The study includes laboratory testing and numerical modeling which considers the influence of boundary conditions on the hydraulic-mechanical behaviour of a compacted unsaturated swelling clay soil. The laboratory testing component of this research consists of three (3) series of tests using a newly modified triaxial apparatus on which mechanical and hydraulic boundary conditions are altered during liquid infiltration. Mechanical boundary conditions range from constant volume to constant mean stress and also include constant stiffness which is a spring type boundary consisting of both volume expansion and mean stress increase. Hydraulic boundary conditions include drained and undrained flow into triaxial specimens. The numerical modeling component of this research includes the creation of a new capillary tube model for swelling clay materials and incorporates dynamic changes to the cross-sectional area for flow. Laboratory results are modeled using the capillary tube model, an empirical hydraulic model, D’Arcy’s Law, and in an elastic-plastic context for unsaturated soil. Results of the laboratory and numerical modeling components show that boundary conditions dominate the hydraulic-mechanical behaviour of unsaturated swelling clay soil during liquid infiltration. In particular, a mechanism is shown to explain how hydraulic conductivity of a swelling soil can decrease with increasing water content at constant void ratio. Finally hydraulic and mechanical behaviour cannot be considered separately in swelling materials due to the intimate relationship in their response.

The hydraulic-mechanical behaviour of swelling clay is examined in this thesis. The study includes laboratory testing and numerical modeling which considers the influence of boundary conditions on the hydraulic-mechanical behaviour of a compacted unsaturated swelling clay soil. The laboratory testing component of this research consists of three (3) series of tests using a newly modified triaxial apparatus on which mechanical and hydraulic boundary conditions are altered during liquid infiltration. Mechanical boundary conditions range from constant volume to constant mean stress and also include constant stiffness which is a spring type boundary consisting of both volume expansion and mean stress increase. Hydraulic boundary conditions include drained and undrained flow into triaxial specimens. The numerical modeling component of this research includes the creation of a new capillary tube model for swelling clay materials and incorporates dynamic changes to the cross-sectional area for flow. Laboratory results are modeled using the capillary tube model, an empirical hydraulic model, D’Arcy’s Law, and in an elastic-plastic context for unsaturated soil. Results of the laboratory and numerical modeling components show that boundary conditions dominate the hydraulic-mechanical behaviour of unsaturated swelling clay soil during liquid infiltration. In particular, a mechanism is shown to explain how hydraulic conductivity of a swelling soil can decrease with increasing water content at constant void ratio. Finally hydraulic and mechanical behaviour cannot be considered separately in swelling materials due to the intimate relationship in their response.

Thesis (M.S.)--University of Michigan, 1982.

Thesis (M.S.)--University of Michigan, 1982.

Thesis (M.S.)--University of Wisconsin--Madison, 1984. / Typescript. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 113-115).

Thesis (M.S.)--University of Wisconsin--Madison, 1983. / Typescript. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 67-70).