Stochastic Modeling of Uncertainties in the Wind Load Pressure on Residential Buildings Using Different Stochastic Techniques

Abstract This paper explores the application of the required loads while performing fitness-for-service (FFS) assessments on an in-service storage tank. Specifically, API 579 – 1, Level 3 FFS assessments involving finite element analyses are studied. In the authors’ experience, due to the absence of specific details about the application of loads within the design codes and post construction standards such as API 579 - 1, the chosen load application is purely at the discretion of the analyst. Often times, choosing one methodology over the other can result in non-conservative assessments. For example, in order to apply wind load pressure distributions on tanks and vessels for plastic collapse and buckling behavior, API 579 – 1 directs the user to ASCE 7 – 16 for wind load calculations. However, previous versions of ASCE 7 did not specify a circumferential pressure distribution for cylindrical structures which can significantly vary around the circumference of a large diameter storage tank. In addition, a few changes in ASCE in the recent edition affect the assessment of in-service tanks for seismic loads. The authors assessed various load cases on tanks of varying diameter to thickness (D/t) ratios and diameter to height ratios. The results show that the choice of loading can have a significant impact on the buckling characteristics of the tanks in-service. This is an attempt to develop some assessment guidelines to support the proposed Tank Assessment Section in a future Edition of API 579 – 1 Standard.

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Wind Load Design of Photovoltaic Power Plants by Comparison of Design Codes and Wind Tunnel Tests

Mathematical Modelling in Civil Engineering ◽

10.2478/mmce-2019-0008 ◽

2019 ◽

Vol 15 (3) ◽

pp. 13-27

Author(s):

Ovidiu Bogdan ◽

Dan Creţu

Keyword(s):

Wind Tunnel ◽

Power Plants ◽

Pressure Coefficient ◽

Wind Tunnel Test ◽

Wind Load ◽

Design Codes ◽

Solar Panels ◽

Design Code ◽

Load Pressure ◽

Pv Panel

Abstract Wind load design of the ground-mounted photovoltaic (PV) power plants requires interpretation of the design code considering the particularities of these structures. The PV power plants consist on systems of several solar panels. Wind load pressure coefficient evaluation, by design code, for a single solar panel considered as a canopy roof, neglect the group effect and the air permeability of the system. On the other hand, the canopy roofs are structures with medium serviceability, but the PV power plants are structures with low serviceability. This paper discuss the difficulties of the wind load design for the PV power plants ground mounted in Romania and compares the Romanian, German, European and American wind design code specifications with the parameters provided by the wind tunnel test, for this type of structures. For Romanian wind load design an evolution of the 1990, 2004 and 2012 editions of the design codes specifications is also studied. Evaluation of the internal resultants for the structural elements of the PV panel, considering the pressure coefficients and the force coefficients, conducts to different results. Further code explanations and design specifications are required for wind design of the PV power plants.

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A Review of the Shell Buckling and Stiffener Ring Design for Cylindrical Steel Storage Tanks

Volume 3: Design and Analysis ◽

10.1115/pvp2016-63204 ◽

2016 ◽

Cited By ~ 2

Author(s):

Eyas Azzuni ◽

Sukru Guzey

Keyword(s):

Circumferential Stress ◽

Local Buckling ◽

Design Procedure ◽

Wind Load ◽

External Pressure ◽

Storage Tanks ◽

Design Standards ◽

Buckling Mode ◽

Load Pressure ◽

Cylindrical Steel

Cylindrical steel storage tanks are shells designed to store different types of products such as liquids or grain. The thickness of the shell is calculated to withstand the circumferential stress resulting from the hydrostatic pressure due to the stored product. A unique situation when there is no stored product leads to the vulnerability of the shell to buckle when there is wind load due to external pressure. There are two major types of buckling modes: local and general. The local buckling mode is studied analytically in various studies and is easy to mitigate. The general buckling mode can be more damaging to the tank and more costly to mitigate. The prevention of general buckling due to wind load pressure is achieved through the addition of stiffener rings. However, the stiffener rings design procedure used by various design standards has little known background. This paper reviews the current design approach’s origin and explains a semi-analytical justification for it. The unfolding of the design expressions can lead to more freedom in design variables selection leading to more economical designs.

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