Sloshing Effects on the Seismic Design of Horizontal-Cylindrical and Spherical Industrial Vessels

2005 ◽  
Vol 128 (3) ◽  
pp. 328-340 ◽  
Author(s):  
Spyros A. Karamanos ◽  
Lazaros A. Patkas ◽  
Manolis A. Platyrrachos
Keyword(s):  
Seismic Design ◽  
Fluid Motion ◽  
Eurocode 8 ◽  
Free Surface Elevation ◽  
Spherical Vessel ◽  
Seismic Force ◽  
Earthquake Design ◽  
Current Design ◽  
Mechanical Models ◽  
Cylindrical Tanks

The present paper investigates sloshing effects on the earthquake design of horizontal-cylindrical and spherical industrial vessels. Assuming small-amplitude free-surface elevation, a linearized sloshing problem is obtained, and its solution provides sloshing frequencies, modes, and masses. Based on an “impulsive-convective” decomposition of the container-fluid motion, an efficient methodology is proposed for the calculation of seismic force. The methodology gives rise to appropriate spring-mass mechanical models, which represent sloshing effects on the container-fluid system in an elegant and simple manner. Special issues, such as the deformability of horizontal-cylindrical containers or the flexibility of spherical vessel supports, are also taken into account. The proposed methodology can be used to calculate the seismic force, in the framework of liquid container earthquake design, and extends the current design practice for vertical cylindrical tanks stated in existing seismic design specifications (e.g., API Standard 650 and Eurocode 8). The methodology is illustrated in three design examples.

Finite Element Analysis of Sloshing in Horizontal-Cylindrical Industrial Vessels Under Earthquake Loading

2005 ◽  
Author(s):  
M. A. Platyrrachos ◽  
S. A. Karamanos
Keyword(s):  
Finite Element Analysis ◽  
Finite Element ◽  
Numerical Solutions ◽  
Fluid Motion ◽  
Element Formulation ◽  
Element Analysis ◽  
Seismic Force ◽  
Current Design ◽  
Cylindrical Tanks ◽  
Horizontal Cylinders

The present paper presents a finite-element formulation for earthquake-induced sloshing in horizontal-cylindrical industrial vessels. Assuming small-amplitude free-surface elevation, a linearized sloshing problem is obtained, which provides very good results in comparison with other analytical or numerical solutions, and available experimental data. The paper is aimed at calculating sloshing frequencies, as well as sloshing transient response under horizontal seismic excitation. Based on an “impulsive-convective” decomposition of the container-fluid motion, an efficient methodology is proposed for the calculation of the total seismic force, through the corresponding sloshing masses. The results from the present finite element analysis offers an efficient tool for predicting the total seismic force in horizontal cylinders and extends the current design practice for vertical cylindrical tanks stated in existing seismic design specifications.

Sloshing Effects on the Seismic Design of Horizontal-Cylindrical and Spherical Vessels

2004 ◽  
Author(s):  
Spyros A. Karamanos
Keyword(s):  
Seismic Design ◽  
Seismic Excitation ◽  
Total Force ◽  
Design Practice ◽  
Efficient Tool ◽  
Seismic Force ◽  
Current Design ◽  
Cylindrical Tanks

The paper concerns earthquake-induced sloshing analysis in horizontal-cylindrical and spherical industrial vessels. More specifically, the paper focuses on the calculation of the total force in such vessels, due to horizontal seismic excitation. The proposed methodology is based on a “impulsive”–“convective” decomposition of the liquid-vessel total motion, widely used in the design of vertical-cylindrical tanks. This method offers a simple and efficient tool for estimating the total seismic force, considering sloshing effects, and extends the current design practice stated in API 650 and EC8 for vertical cylindrical tanks.

scholarly journals Comparative study of codes for the seismic design of structures

2012 ◽  
Vol 5 (6) ◽  
pp. 812-819
Author(s):  
S. H. C. Santos ◽  
S. S. Lima ◽  
A. Arai
Keyword(s):  
Seismic Design ◽  
Response Spectra ◽  
Soil Liquefaction ◽  
Eurocode 8 ◽  
South American ◽  
The South ◽  
Seismic Zonation ◽  
Seismic Force ◽  
Western Border ◽  
Definition Of

A general evaluation of some points of the South American seismic codes is presented herein, comparing them among themselves and with the American Standard ASCE/SEI 7/10 and with the European Standard Eurocode 8. The study is focused in design criteria for buildings. The Western border of South America is one of the most seismically active regions of the World. It corresponds to the confluence of the South American and Nazca plates. This region corresponds roughly to the vicinity of the Andes Mountains. This seismicity diminishes in the direction of the comparatively seismically quieter Eastern South American areas. The South American countries located in its Western Border possess standards for seismic design since some decades ago, being the Brazilian Standard for seismic design only recently published. This study is focused in some critical topics: definition of the recurrence periods for establishing the seismic input; definition of the seismic zonation and design ground motion values; definition of the shape of the design response spectra; consideration of soil amplification, soil liquefaction and soil-structure interaction; classification of the structures in different importance levels; definition of the seismic force-resisting systems and respective response modification coefficients; consideration of structural irregularities and definition of the allowable procedures for the seismic analyses. A simple building structure is analyzed considering the criteria of the several standards and obtained results are compared.

Assessment of current design procedures for conical tanks under seismic loading

2013 ◽  
Vol 40 (12) ◽  
pp. 1151-1163 ◽  
Author(s):  
M. Jolie ◽  
M.M. Hassan ◽  
A.A. El Damatty
Keyword(s):  
Hydrodynamic Pressure ◽  
American Petroleum Institute ◽  
Eurocode 8 ◽  
Design Codes ◽  
Base Shear ◽  
Seismic Excitations ◽  
Equivalent Mechanical Model ◽  
Current Design ◽  
Conical Tanks ◽  
Cylindrical Tanks

This study is motivated by the fact that no design provisions currently exist specifically for conical tanks under seismic excitations. The design of liquid storage structures is governed by the American Water Works Association (AWWA), American Petroleum Institute (API), or Eurocode 8. An approximate method based on replacing the conical tank with an equivalent cylinder is given in these design codes. The state of stresses in conical tanks is different than that of cylindrical tanks. A previously established equivalent mechanical model is used to determine the response of a number of conical tanks under horizontal excitations. The models incorporate the different components of the hydrodynamic pressure and account for flexibility of the tank walls. Using an assortment of seismic hazard areas, the maximum base shear force and overturning moment are evaluated for a number of conical tanks. Those are compared to the corresponding values predicted by the design codes using the equivalent cylinder approach. The results reveal that this approximate approach is not adequate for designing conical tanks to resist seismic excitations.

scholarly journals Experimental Study on the Behavior of Existing Reinforced Concrete Multi-Column Piers under Earthquake Loading

2021 ◽  
Vol 11 (6) ◽  
pp. 2652
Author(s):  
Jung Han Kim ◽  
Ick-Hyun Kim ◽  
Jin Ho Lee
Keyword(s):  
Seismic Performance ◽  
Seismic Design ◽  
Bridge Piers ◽  
Scale Model ◽  
Inertia Force ◽  
Small Scale ◽  
Lap Splice ◽  
Existing Structures ◽  
Seismic Design Code ◽  
Seismic Force

When a seismic force acts on bridges, the pier can be damaged by the horizontal inertia force of the superstructure. To prevent this failure, criteria for seismic reinforcement details have been developed in many design codes. However, in moderate seismicity regions, many existing bridges were constructed without considering seismic detail because the detailed seismic design code was only applied recently. These existing structures should be retrofitted by evaluating their seismic performance. Even if the seismic design criteria are not applied, it cannot be concluded that the structure does not have adequate seismic performance. In particular, the performance of a lap-spliced reinforcement bar at a construction joint applied by past practices cannot be easily evaluated analytically. Therefore, experimental tests on the bridge piers considering a non-seismic detail of existing structures need to be performed to evaluate the seismic performance. For this reason, six small scale specimens according to existing bridge piers were constructed and seismic performances were evaluated experimentally. The three types of reinforcement detail were adjusted, including a lap-splice for construction joints. Quasi-static loading tests were performed for three types of scale model with two-column piers in both the longitudinal and transverse directions. From the test results, the effect on the failure mechanism of the lap-splice and transverse reinforcement ratio were investigated. The difference in failure characteristics according to the loading direction was investigated by the location of plastic hinges. Finally, the seismic capacity related to the displacement ductility factor and the absorbed energy by hysteresis behavior for each test were obtained and discussed.

scholarly journals Parametric Analysis of Rotational Effects in Seismic Design of Tall Structures

2021 ◽  
Vol 11 (2) ◽  
pp. 597
Author(s):  
Milan Sokol ◽  
Rudolf Ároch ◽  
Katarína Lamperová ◽  
Martin Marton ◽  
Justo García-Sanz-Calcedo
Keyword(s):  
Seismic Design ◽  
Parametric Study ◽  
Tall Buildings ◽  
Soil Parameters ◽  
Eurocode 8 ◽  
Tall Structures ◽  
Rotational Components ◽  
Different Types ◽  
Depth Study

This paper uses a parametric study to evaluate the significance of the rotational components of Earth’s motion in a seismic design. The parametric study is based on the procedures included in Eurocode 8, Part 6. Although the answer to the question of when the effects of rotational components are important is quite a complex one and requires a more in-depth study, our aim was to try to assess this question in a relatively quick manner and with acceptable accuracy. The first part of the paper is devoted to derivation of a simple formula that can be used for expressing the importance of rotational components in comparison with the classic seismic design without their usage. The quasi-static analysis, assuming inertial forces, is used. A crucial role plays the shape of the fundamental mode of the vibration. Due to simplicity reasons, well-known expression for estimation of the first eigenmode as an exponential function with different power coefficients that vary for different types of buildings is used. The possibility of changing the soil parameters is subsequently included into the formula for estimation of the fundamental frequency of tall buildings. In the next part, the overall seismic analyses of complex FEM models of 3D buildings and chimneys are performed. The results from those analyses are then compared with those from simplified calculations. The importance of the soil characteristics for determination of whether it is necessary to take into account the rotational effects is further discussed.

Lateral Force Resisting Systems Made of Cold-Formed Steel Material: Proposal of Seismic Design Criteria for 2nd Generation of Eurocode 8

2021 ◽  
Vol 885 ◽  
pp. 127-132
Author(s):  
Sarmad Shakeel ◽  
Alessia Campiche
Keyword(s):  
Seismic Design ◽  
Shear Walls ◽  
Lateral Force ◽  
Background Information ◽  
Design Criteria ◽  
Eurocode 8 ◽  
Building Structures ◽  
Design Standards ◽  
Design Strength ◽  
Cold Formed Steel

The current edition of Eurocode 8 does not cover the design of the Cold-Formed steel (CFS) building structures under the seismic design condition. As part of the revision process of Euro-code 8 to reflect the outcomes of extensive research carried out in the past decade, University of Naples “Federico II” is involved in the validation of existing seismic design criteria and development of new rules for the design of CFS systems. In particular, different types of Lateral Force Resisting System (LFRS) are analyzed that can be listed in the second generation of Eurocode 8. The investigated LFRS’s include CFS strap braced walls and CFS shear walls with steel sheets, wood, or gypsum sheathing. This paper provides the background information on the research works and the reference design standards, already being used in some parts of the world, which formed the basis of design criteria for these LFRS systems. The design criteria for the LFRS-s common to CFS buildings would include rules necessary for ensuring the dissipative behavior, appropriate values of the behavior factor, guidelines to predict the design strength, geometrical and mechanical limitations.

Sign in / Sign up

Export Citation Format

Share Document