The Experts below are selected from a list of 1287672 Experts worldwide ranked by ideXlab platform
Hong Hao - One of the best experts on this subject based on the ideXlab platform.
-
Proposed Design procedure for reinforced concrete bridge columns subjected to vehicle collisions
Structures, 2019Co-Authors: Thong M Pham, Hong HaoAbstract:Abstract In this study, analytical investigation and numerical simulations are utilized to examine the responses of reinforced concrete bridge columns (RCBC) against vehicle collisions. Based on the numerical results, a simplified approach is developed for analysis and Design of RCBCs to resist vehicle collisions. RCBCs impacted by a medium truck and a heavy truck trailer at different velocities are considered. Based on the numerical results, empirical equations to determine the maximum shear force and bending moment at column critical sections are Proposed. A single-degree-of-freedom (SDOF) system is employed to predict the dynamic response of the column. A procedure to Design RCBCs under vehicle collision with either flexural bending or brittle shear failure governed response of the column is Proposed. Two Design examples of RCBC under medium truck impact and heavy truck impact are given in this study to demonstrate the Proposed procedure.
Dennis K. Williams - One of the best experts on this subject based on the ideXlab platform.
-
Proposed Design Criterion for Vessel Lifting Lugs in Lieu of ASME B30.20
Journal of Pressure Vessel Technology, 2006Co-Authors: Dennis K. WilliamsAbstract:This paper describes a method for evaluating the structural adequacy of various lifting lugs utilized in the erection and up righting of large pressure vessels. In addition, the analysis techniques are described in detail and Design guidelines for vessel lifting are tendered. The statutory and provincial regulations in both the United States and the province of Alberta, Canada are also reviewed and discussed with respect to the too often utilized phrase "factor of safety" (FOS). The implied implications derived from the chosen FOS are also outlined. A discussion is presented as to the applicability of the ASME safety standard B30.20 entitled, "Below the Hook Lifting Devices" (1999, ASME, New York) and as to the severe shortcomings of the safety standard in its attempt to delve into the Design of lifting devices, especially when applied to lifting lugs on large and heavy-weight pressure vessels. Exemplar lugs on vessels are defined and the finite element analyses and closed form Hertzian contact problem solutions are presented and interpreted in accordance with the Proposed Design criteria. These results are compared against the very limited Design information contained within ASME B30.20. Suggestions for the revision and applicability of the safety standard are presented and discussed in light of the examples and technical justification presented in the following paragraphs. In addition, the silence of this safety standard on the very large contact stresses that are well known to exist between a lifting pin and clevis type geometry is also discussed. Because of the limited number of repetitive loading cycles that vessel lifting lugs actually experience during the service life of a vessel, a recommendation is made to either clearly exclude vessel lifting lugs from the scope of ASME B30.20 or to specifically include a separate Design and analysis section within this standard to properly address the mechanical and structural Design issues applicable to pressure vessel lifting lugs.
-
A Proposed Design Criterion for Vessel Lifting Lugs in Lieu of ASME B30.20
Design and Analysis of Piping Vessels and Components, 2002Co-Authors: Dennis K. WilliamsAbstract:This paper describes a method for evaluating the structural adequacy of various lifting lugs utilized in the erection and up righting of large pressure vessels. In addition, the analysis techniques are described in detail and Design guidelines for vessel lifting are tendered. The statutory and provincial regulations in both the United States and the province of Alberta, Canada are also reviewed and discussed with respect to the too often utilized phrase “factor of safety” (FOS). The implied implications derived from the chosen FOS are also outlined. A discussion is presented as to the applicability of the ASME safety standard B30.20 [1] entitled, “Below the Hook Lifting Devices” and as to the severe shortcomings of the safety standard in its attempt to delve into the Design of lifting devices, especially when applied to lifting lugs on large and heavy-weight pressure vessels. Exemplar lugs on vessels are defined and the finite element analyses and closed form Hertzian contact problem solutions are presented and interpreted in accordance with the Proposed Design criteria. These results are compared against the very limited Design information contained within ASME B30.20 [1]. Suggestions for the revision and applicability of the Below the Hook Lifing Devices safety standard and presented and discussed in light of the examples and technical justification presented in the following paragraphs. In addition, the silence of the referenced safety standard on the very large contact stresses that are well known to exist between a lifting pin and clevis type geometry is also discussed. Due to the limited number of repetitive loading cycles that vessel lifting lugs acturally experience during the service life of a vessel, a recommendation is made to either clearly exclude vessel lifting lugs from the scope of ASME B30.20 [1] or to specifically include a separate Design and analysis section within the referenced stardard to properly address the mechanical and structural Design issues applicable to pressure vessel lifting lugs.
Shahab Ramhormozian - One of the best experts on this subject based on the ideXlab platform.
-
Proposed Design models for the asymmetric friction connection
Earthquake Engineering & Structural Dynamics, 2014Co-Authors: Hsen-han Khoo, Charles Clifton, Gregory A. Macrae, Hao Zhou, Shahab RamhormozianAbstract:KTA (Sarawak) Sdn Bhd, No. 33, Jalan SS 24/8, Taman Megah, 47301 Petaling Jaya, Selangor Darul Ehsan, Malaysia Department of Civil Engineering, Unitec Institute of Technology, Carrington Road, Private Bag 92025, Auckland 1025, New Zealand Department of Civil and Environmental Engineering, The University of Auckland, Private Bag 92019, Auckland 1142, New Zealand Department of Civil and Natural Resources Engineering, University of Canterbury, Private Bag 4800, Christchurch 8140, New Zealand AECOM, AECOM House, PO Box 4241 Shortland St, Auckland 1140, New Zealand
Thong M Pham - One of the best experts on this subject based on the ideXlab platform.
-
Proposed Design procedure for reinforced concrete bridge columns subjected to vehicle collisions
Structures, 2019Co-Authors: Thong M Pham, Hong HaoAbstract:Abstract In this study, analytical investigation and numerical simulations are utilized to examine the responses of reinforced concrete bridge columns (RCBC) against vehicle collisions. Based on the numerical results, a simplified approach is developed for analysis and Design of RCBCs to resist vehicle collisions. RCBCs impacted by a medium truck and a heavy truck trailer at different velocities are considered. Based on the numerical results, empirical equations to determine the maximum shear force and bending moment at column critical sections are Proposed. A single-degree-of-freedom (SDOF) system is employed to predict the dynamic response of the column. A procedure to Design RCBCs under vehicle collision with either flexural bending or brittle shear failure governed response of the column is Proposed. Two Design examples of RCBC under medium truck impact and heavy truck impact are given in this study to demonstrate the Proposed procedure.
Eric Sumner - One of the best experts on this subject based on the ideXlab platform.
-
Proposed Design guidelines for strengthening of steel bridges with frp materials
Construction and Building Materials, 2007Co-Authors: David Schnerch, Sami Rizkalla, Mina Dawood, Eric SumnerAbstract:Abstract This paper focuses on the use of externally bonded high modulus carbon fiber reinforced polymer (HM CFRP) materials to strengthen steel bridges and structures. Proper installation of the CFRP materials is necessary to prevent premature failure due to debonding. The paper proposes guidelines and installation techniques based on the best practice reported in the literature and the extensive practical experience in bonding of composite materials. The surface preparation of the materials, the application of the adhesive and the detailing of the strengthening are provided in detail. The Design guidelines include the structural Design criteria for the use of high modulus CFRP materials as flexural strengthening system of typical steel–concrete composite bridge girders. The flexural Design procedure is based on a moment–curvature analysis and a specified increase of the live load carried by the bridge to satisfy specific serviceability requirements. A bond model is also described which can be used to calculate the shear and peel stresses within the adhesive thickness. To prevent a premature debonding failure of the strengthening system, the criteria specify a maximum principle stress in the adhesive which cannot be exceeded for a given characteristic strength of an adhesive. A worked example is presented to illustrate the Proposed flexural Design approach. The research findings conclude that high modulus CFRP materials provide a promising alternative for strengthening steel bridges that can be easily Designed and installed to increase their strength and stiffness.
