1 Copyright © 2010 by ASME Proceedings of the ASME 2010 29 th International Conference on Ocean, Offshore and Arctic Engineering OMAE2010 June 6-11, 2010, Shanghai, China OMAE2010-20440 CRUSHING TESTS OF FLOWLINES INTERNAL LAYERS: AN EXPERIMENTAL APPROACH VIA OPTICAL MOTION CAPTURE AND IMAGE PROCESSING André L. C. Fujarra 1 (afujarra@usp.br ) Rodolfo T. Gonçalves 1 (rodolfo_tg@tpn.usp.br ) Celso P. Pesce 2 (ceppesce@usp.br ) Marcelo R. Silva 3 (marcelo.silva@prysmian.com ) Carlos A. F. Godinho 3 (carlos.godinho@prysmian.com ) 1 TPN – Numerical Offshore Tank Department of Naval Architecture and Ocean Engineering, Escola Politécnica – University of São Paulo São Paulo, SP, Brazil 2 LIFE&MO – Fluid Structure Interaction and Offshore Mechanics Laboratory Department of Mechanical Engineering, Escola Politécnica – University of São Paulo São Paulo, SP, Brazil 3 Prysmian Cables and Systems Vila Velha, ES, Brazil ABSTRACT New optical measurement approach for crushing tests of flow lines internal layers is detailed, based on an accurate tracking of the deformed carcass section through image processing. The results are compared to those from standard procedures based on discrete measurements using calipers. The new approach shows to be not only appropriate for the standard measurement requirements but also enables a comprehensive understanding of the crushing behavior. NOMENCLATURE CC correlation coefficient DH horizontal diameter DH 0 horizontal diameter at the initial instant DV vertical diameter DV 0 vertical diameter at the initial instant F force Z vertical position of the marker 1. INTRODUCTION A design methodology for flexible pipes flow lines has been developed, regarding global and local structural analysis, flow assurance and gas permeation issues, material selection and fabrication processes, as well as installation and reliability. A number of tests was carried out concerning the investigation of specific failure modes. Collapse and crushing of the internal carcass are some of the numerous failure modes addressed. Among the experimental procedures, simple crushing tests may be a quite useful source of theoretical and practical information for the local structural analysis models. Besides, such tests provide specific data on plastic deformation of the carcass and its implications in establishing limit loads for the laying operation, as well as in eventual pigging inspection. In this context, the present paper addresses a new experimental approach. Such an approach applies an accurate position tracking and stereoscopic image processing method. The methodology is described in the text and applied to a 4-inch flexible pipe carcass case. Proceedings of the ASME 2010 29th International Conference on Ocean, Offshore and Arctic Engineering OMAE2010 June 6-11, 2010, Shanghai, China OMAE2010-