Structural Performance Optimization and Verification of an Improved Thin-Walled Storage Tank for a Pico-Satellite

One of major difficulties in developing and employing a concept model of a vehicle is to develop a simple and accurate model of joints. A vehicle joint is a subassembly formed by several members that intersect together. It is a thin-walled structure formed by overlapping metal sheets fastened by spot welds. The study of the joints has been important, because they can deform locally. This flexibility can affect noise, vibration and harshness (NVH) characteristics of a vehicle plus other structural performance characteristics under different loading conditions. The main difference between various kinds of concept models is the representation of body joints. Joints are important components of the auto body because they affect significantly, and in some cases, they even dominate, the static and dynamic behavior of a model. This paper introduces a new beam-like major compliant joint methodology. Joints are simulated with different parametric representations that present the major differences among various concept models. The development procedure of the beam-like major compliant joint is explained and the benefits of using this representation are discussed.

Download Full-text

Behaviors of Thin-Walled Cylindrical Shell Storage Tank under Blast Impacts

Shock and Vibration ◽

10.1155/2019/6515462 ◽

2019 ◽

Vol 2019 ◽

pp. 1-21

Author(s):

Shengzhuo Lu ◽

Wei Wang ◽

Weidong Chen ◽

Jingxin Ma ◽

Yaqin Shi ◽

...

Keyword(s):

Storage Tank ◽

Structural Response ◽

Scale Model ◽

Dynamic Strain ◽

Economic Losses ◽

Long Span ◽

Large Structures ◽

Structural Responses ◽

Thin Walled ◽

The Impact

Large steel storage tanks designed with long-span structures, employed for storing oil and fuel, have been widely used in many countries over the past twenty years. Most of these tanks are thin-walled cylindrical shells. Owing to the high risk of gas explosions and the resulting deaths, injuries, and economic losses, more thorough damage analyses of these large structures should be conducted. This study examines the structural response of a simplified steel storage tank under a blast impact, as calculated by the LS-DYNA software package. The numerical results are then compared with a scale-model experiment. On that basis, the simplified storage tank prototype, which has a 15 × 104 m3 capacity, is analyzed using numerical simulation. In this study, we address issues around the variation in structural responses—particularly of the failure mode, resultant displacement, structural energy, and dynamic strain under the impact. In addition, we also discuss the effects of varying the internal liquid level, constraint conditions, and blast intensity.

Download Full-text

Spot Weld Layout Optimization With Manufacturing Constraints for Vehicle Structural Performance

Volume 3: Design and Manufacturing, Parts A and B ◽

10.1115/imece2010-40376 ◽

2010 ◽

Cited By ~ 1

Author(s):

Xueyuan Wu ◽

Yong Xia ◽

Qing Zhou ◽

Wayne Cai ◽

Robert B. Tilove

Keyword(s):

Influencing Factor ◽

Layout Design ◽

Layout Optimization ◽

Absorption Capacity ◽

Spot Weld ◽

Structural Performance ◽

Manufacturing Constraints ◽

Thin Walled Tube ◽

Thin Walled ◽

Crash Performance

Spot weld layout on thin walled vehicle structures is an influencing factor to the structural performance such as NVH, durability and crashworthiness. The weld layout is also subject to manufacturing constraints such as minimum weld pitch, thickness and curvature of flanges, and accessibility of weld gun. Using an S-shaped thin walled tube as an example, this paper presents a study of spot weld layout optimization considering both structural performance and manufacturing constraints for reducing design iterations between the performance design and the manufacturing design. First, several complex manufacturing constraints, including minimum spot weld pitch, maximum curvature of flange, etc., are mathematically characterized. Then, with and without typical manufacturing constraints, the weld layout is optimized respectively for crash performance and torsion performance of the structure. The effects of adding manufacturing constraints on the spot weld layout optimization are evaluated. The analysis results reveal that the crash performance responses are generally less sensitive to the spot weld layout while the torsion stiffness is closely related to the spot weld layout. To analyze why the crash performance is less dependent on the weld layout, a detailed study is further conducted to reveal the relation between the weld layout and the crash performance of S-shaped thin walled tube. It shows that the parameters for assessing the structural crash performance have distinct sensitivity to the spot weld layout design. For instance, the peak impact force is generally sensitive to the spot welds placed in the curved segment and the total energy absorption capacity is mainly determined by the curvature design of the tube instead of the spot weld layout design.

Download Full-text

Investigation on Buckling Behavior of Cylindrical Liquid Storage Tanks Under Seismic Excitation: 1st Report — Investigation on Elephant Foot Bulge

Seismic Engineering ◽

10.1115/pvp2003-2120 ◽

2003 ◽

Author(s):

Tomohiro Ito ◽

Hideyuki Morita ◽

Koji Hamada ◽

Akihisa Sugiyama ◽

Yoji Kawamoto ◽

...

Keyword(s):

Storage Tank ◽

Nuclear Power ◽

Power Plants ◽

Large Scale ◽

Storage Tanks ◽

Scaled Model ◽

Liquid Storage ◽

Shear Buckling ◽

Thin Walled ◽

Liquid Storage Tank

When a thin walled cylindrical liquid storage tank suffers a large seismic base excitation, buckling phenomena may be caused such as bending buckling at the bottom portion and shear buckling at the middle portion of the tank. However, the dynamic behaviors of the tanks is not fully clarified, especially those from the occurrence of buckling to some failures. In this study, bending buckling phenomena were focused which will be categorized as diamond buckling and elephant foot bulge. As ones of a series of studies, dynamic buckling tests were performed using large scale liquid storage tank models simulating thin walled cylindrical liquid storage tanks in nuclear power plants. The input seismic acceleration was increased until the elephant foot bulge occurred, and the vibrational behavior before and after buckling was investigated. In addition to the large scaled model tests, fundamental tests using small scaled tank models were also performed in order to clarify the effects of dynamic liquid pressure on the buckling threshold and deformation patterns.

Download Full-text

Structural performance of T-stub end plate joints to thin walled concrete filled steel tube columns

10.1063/1.4965076 ◽

2016 ◽

Author(s):

A. Z. Nazrul Azmi ◽

P. Clotilda ◽

A. H. Hanizah ◽

I. Azmi

Keyword(s):

Steel Tube ◽

Structural Performance ◽

Concrete Filled Steel Tube ◽

End Plate ◽

Thin Walled ◽

Stub End

Download Full-text

Structural performance of blind bolted end plate joints to concrete-filled thin-walled steel tubular columns

Thin-Walled Structures ◽

10.1016/j.tws.2012.07.006 ◽

2012 ◽

Vol 60 ◽

pp. 54-68 ◽

Cited By ~ 35

Author(s):

Jingfeng Wang ◽

Shuiping Guo

Keyword(s):

Structural Performance ◽

Tubular Columns ◽

End Plate ◽

Thin Walled

Download Full-text

Influence of Angle Thickness towards Stiffness and Strength Prediction for Cold-Formed Steel Top-Seat Flange Cleat Connection

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.479-480.1144 ◽

2013 ◽

Vol 479-480 ◽

pp. 1144-1148 ◽

Cited By ~ 1

Author(s):

Yeong Huei Lee ◽

Cher Siang Tan ◽

M.Md. Tahir ◽

Shahrin Mohammad ◽

Poi Ngian Shek ◽

...

Keyword(s):

Finite Element ◽

Finite Element Modelling ◽

Structural Integrity ◽

Structural Performance ◽

Design Stage ◽

Strength Prediction ◽

Finite Element Models ◽

Steel Framing ◽

Cold Formed Steel ◽

Thin Walled

For the connection stiffness and strength prediction, Eurocode has showed an inadequacy as it will be affected by the thin-walled behaviour of cold-formed steel in actual structural performance. This paper performs a study on the connection stiffness prediction for cold-formed steel top-seat flange cleat connection with various angle thickness. Validated finite element modelling technique is applied for further advanced investigation. From the developed finite element models, it was realized that Eurocode has overestimated by the analytical stiffness prediction using component method for the studied connection which reduces the structural integrity in the design stage. A new proposal on connection stiffness prediction with influence of angle thickness for cold-formed steel top-seat flange cleat connection is presented to assist practicing engineers to design the cold-formed connection in light steel framing.

Download Full-text