GLOBAL ANALYSIS OF THE PENETRATION OF A TORPEDO ANCHOR MODELED BY PANEL MESH
Carolina Maria Nunes Bezerra1; Fabrício Nogueira Corrêa1; Jhonathan Jhefferson de Sousa Ribeiro1; Adolfo Emmanuel Correa López1; Breno Pinheiro Jacob1
1 COPPE/UFRJ
doi:10.20906/CPS/CILAMCE2017-0039
Resumo
The present paper has the objective to study the penetration of a torpedo anchor modeled by panels mesh for a given depth profile and load capacity, considering the real torpedo geometry also considering the influence of their four flukes. This approach was developed to be used in global analyses with low computational cost and is intended to represent the complete geometry of the UEP torpedo anchor by panel mesh of triangular elements. Their normal and tangential forces is given by True model to represent the contact between the anchor and sea floor. This new method is associated to the weak coupled dynamic analyses in time domain, in which the torpedo is represented by a rigid body with six degree of freedom and the anchor and launching lines can be represented by Finite Elements. The soil reaction in the torpedo is evaluated by numerical integral of the soil pressure on its penetrated surface area, represented by an adaptive mesh with triangular elements, in which allow to consider rigorously the geometry of the body. The method was developed on in-house program SITUA-Prosim and was compared with the classical True model and the data obtained by a real launching procedure evaluated in Campus Basin, Brazil. For numerical simulations, the same physical data were used to represent the saturated clay soil of the region and the torpedo starting from the release height of 150m from seabed. Therefore, considering the same impact velocity, the final numerical penetration depth reached values close to that observed in the field. The influence of the flukes on the penetration depth will also be evaluated. The computational method presented has an efficient computational cost and accurate results to be used in global analysis in design of anchor systems based on torpedo anchor.
Palavras-chave: Torpedo anchor; True model; Panel mesh; Shear resistance; Drag coefficient