Investigation on the Post-Ultimate Strength Behaviour of Damaged Stiffened Plate of Ship Structure

2016 ◽  
Author(s):  
Weijun Xu ◽  
Minjie Yuan ◽  
Xiaotian Wang
Keyword(s):  
Ultimate Strength ◽  
Carrying Capacity ◽  
Crack Depth ◽  
Plate Thickness ◽  
Longitudinal Crack ◽  
Load Carrying Capacity ◽  
Stiffened Plate ◽  
Ship Structure ◽  
Plate Length ◽  
Load Carrying

Post-ultimate strength behaviour of ship structure can directly reflect its changing tendency of load carrying capacity. When the external load exerted on the ship structure exceeds the ultimate strength, sharply reduction of load carrying capacity will occur, especially for the damaged ship structure induced from grounding or collision. This paper focuses on the investigation on the post-ultimate strength behaviour of damaged stiffened plate of ship structure by using FEM, a series of stiffened plate modeling with different kinds of cracks are constructed. The parameters of crack includes length, width, depth, plate thickness and distribution direction. The post-ultimate strength behaviour of stiffened plate with cracks and intact ones are compared. Conclusion can be drawn as follows: (1) crack can induce the reduction of ultimate strength of stiffened plate, meanwhile, the stiffness and its load carrying capacity decrease accordingly. (2) in terms of stiffened thin plate, length of crack has a significant influence on the post-ultimate strength behaviour, the width of the crack has a huge influence on ultimate strength while the depth of crack has little influence; in terms of stiffened thick plate, the influence of crack depth on the post-ultimate strength behaviour becomes obvious. The width of the crack influence the post-ultimate strength behaviour a lot. (3) compare to the transverse crack, the influence of longitudinal crack on the post-ultimate strength behaviour is not obvious.

Investigation on the Post-Ultimate Strength Behaviour of Sandwich Plate

2014 ◽  
Author(s):  
Wei Wang ◽  
Weijun Xu ◽  
Xiongliang Yao ◽  
Nana Yang
Keyword(s):  
Ultimate Strength ◽  
Carrying Capacity ◽  
Failure Modes ◽  
Sandwich Plate ◽  
Experimental Results ◽  
Sandwich Plates ◽  
Load Carrying Capacity ◽  
Load Carrying ◽  
Strength Behavior ◽  
Simulation Results

This paper focuses on the post-ultimate strength behavior of sandwich plates. With widely application of the laminate on the ship and offshore structures, the post-ultimate strength behavior is becoming more important for safety evaluation of structures. Since the post-ultimate strength behavior can reflect the collapse extent of sandwich plate when subjected to extreme loads. A sandwich plate was modeled by FEM, its load-displacement relationship was obtained and its collapse characteristics were analyzed. The load-displacement relationship indicates its post-ultimate strength behavior, which is shown as that the load carrying capacity has a rapidly reduction when the ultimate strength is exceeded, and that the failure modes of the sandwich plate are determined by the parameter of individual layer. The simulation results were validated against experimental results. Conclusions are drawn: the displacement of sandwich plate under axial compression increased slowly before reaching the ultimate strength, once the ultimate strength was exceeded, the loads exerted on the structures sharply decreased with slowly increased displacement until the plate cracked. The simulation results have a good agreement with the experimental results. The mainly failure modes of sandwich plates can be interpreted as delamination between skin & core and core compression fracture, which are typical failure modes in engineering. The stiffness of sandwich structures decreased due to the interlaminar cracking or skin fracture, further the load carrying capacity decreased, which is of significance for guiding the design of sandwich structures.

Ultimate Load-Carrying Capacity of Pipe-Plate Vierendeel Truss Joints

2013 ◽  
Vol 838-841 ◽  
pp. 503-509
Author(s):  
Jie Luo ◽  
Jian Chun Xiao ◽  
Zhe Lu ◽  
Xiao Xiao Wei ◽  
Hong Xi Li ◽  
...  
Keyword(s):  
Axial Force ◽  
Carrying Capacity ◽  
Failure Modes ◽  
Ultimate Load ◽  
Plate Thickness ◽  
Load Carrying Capacity ◽  
Plate Height ◽  
Joint Failure ◽  
Load Carrying ◽  
Ultimate Load Carrying Capacity

To study the ultimate load-carrying capacity of pipe-plate Vierendeel truss joints, the analyses of joint failure modes and parameter effects were undertaken using nonlinear finite element method and uniform design approach. The plate instability was included in the failure modes. Factors such as the pipe diameter, the pipe thickness, the plate width, the plate height, and the plate thickness were considered in the joint models. Three kind of loading conditions on the plate, the axial force, the moment, the composed loading of axial force and moment were analyzed. The relationships between the joint failure modes and the factors are achieved. The joint ultimate load-bearing capacity formulas are proposed by regression analysis. The effects of factors on the joint strength are illustrated.

scholarly journals Crack Width and Load-Carrying Capacity of RC Elements Strengthened with FRP

2018 ◽  
Vol 2018 ◽  
pp. 1-14 ◽  
Author(s):  
Justas Slaitas ◽  
Mykolas Daugevičius ◽  
Juozas Valivonis ◽  
Tatjana Grigorjeva
Keyword(s):  
Crack Propagation ◽  
Carrying Capacity ◽  
Crack Width ◽  
Crack Depth ◽  
Experimental Program ◽  
Mechanics Of Solids ◽  
Crack Model ◽  
Load Carrying Capacity ◽  
Rc Structures ◽  
Load Carrying

The present study focuses on a prediction of crack width and load-carrying capacity of flexural reinforced concrete (RC) elements strengthened with fibre-reinforced polymer (FRP) reinforcements. Most studies on cracking phenomena of FRP-strengthened RC structures are directed to empirical corrections of crack-spacing formula given by design norms. Contrary to the design norms, a crack model presented in this paper is based on fracture mechanics of solids and is applied for direct calculation of flexural crack parameters. At the ultimate stage of crack propagation, the load-carrying capacity of the element is achieved; therefore, it is assumed that the load-carrying capacity can be estimated according to the ultimate crack depth (directly measuring concrete’s compressive zone height). An experimental program is presented to verify the accuracy of the proposed model, taking into account anchorage and initial strain effects. The proposed analytical crack model can be used for more precise predictions of flexural crack propagation and load-carrying capacity.

Remaining Capacity of Corroded Gusset Plate Connection

2019 ◽  
Author(s):  
Takeshi Miyashita ◽  
Ngoc Vinh Pham ◽  
Kazuo Ohgaki ◽  
Yusuke Okuyama ◽  
Yuya Hidekuma ◽  
...  
Keyword(s):  
Carrying Capacity ◽  
Plate Thickness ◽  
Fem Analysis ◽  
Load Carrying Capacity ◽  
Loading Test ◽  
Cross Sectional ◽  
Gusset Plate ◽  
Load Carrying ◽  
Remaining Capacity ◽  
Plate Connection

<p>Nowadays, severe damage on the gusset plate connection of steel truss bridges due to corrosion has been widely reported all over the world. In this context, the remaining load-carrying capacity of a corroded gusset plate connection was evaluated by using the loading test and Finite Element Method (FEM) analysis. Two potential forms of corrosion on the gusset plate, namely welding and cross-sectional corrosion, were proposed to investigate the reduction of load-carrying capacity. The overall FEM model dimension for the real bridge was scaled down by a percentage of 50%. The degrees of corrosion sections were assumed disconnected at about 50% of the weld length and the loss of the gusset plate thickness was 50% and 75%. Parametric FEM analysis was performed to evaluate the effect of the degree of corrosion on the remaining load-carrying capacity of the gusset plate connection.</p>

EFFECTS OF WEB OPENINGS ON SHEAR BEHAVIOUR OF NORMAL AND INTERNALLY STRENGTHENED CONCRETE BEAMS

2021 ◽  
Author(s):  
Burhan Ahmad ◽  
Muhammad Yousaf ◽  
Muhammad Irfan-ul-Hassan ◽  
Muhammad Burhan Sharif ◽  
Zahid Ahmed Siddiqi ◽  
...  
Keyword(s):  
Ultimate Strength ◽  
Carrying Capacity ◽  
Ultimate Load ◽  
Shear Zones ◽  
Shear Behaviour ◽  
Load Carrying Capacity ◽  
Rc Beams ◽  
Shear Reinforcement ◽  
Web Openings ◽  
Load Carrying

Web openings in reinforced concrete (RC) beams are provided to pass utility pipes and ducts through them. This causes high stresses (with local cracking) around the transverse web openings, which may lead to reduction in ultimate strength and stiffness of RC beams. Internal strengthening with shear reinforcement can increase ultimate strength of the beam with web openings. This paper presents an experimental study which was conducted to investigate load carrying capacity, mid-span deflection and failure modes of beams with web openings. A total of eighteen RC beams were included in the testing programme, which were tested under two-point loading. The beams contained both pre-planned and post-planned web openings. Experimental results showed that ultimate load of the beams decreased from forty-two to sixty-seven percent due to the presence of web openings in the shear zones. Shear strength of the beams with pre-planned web openings increased by thirty-six percent and one-hundred two percent as compared to the reference beam due to the increase of shear reinforcement by one-hundred twenty-two percent and three-hundred three percent, respectively. Similarly, increase in shear capacity up to six percent and fourteen percent was found for the beams with post-planned web openings due to the aforementioned increase in the area of shear reinforcement, respectively. The ultimate load carrying capacity was also compared with the theoretical models. Internal strengthening and pre planned opening were found effective for providing web openings in the beams.

Ultimate Strength of Damaged Stiffened Panels Subjected to Uniaxial Compressive Loads Accounting for Impact Induced Residual Stress and Deformation

2015 ◽  
Author(s):  
Jie Cai ◽  
Xiaoli Jiang ◽  
Gabriel Lodewijks
Keyword(s):  
Residual Stress ◽  
Ultimate Strength ◽  
Carrying Capacity ◽  
Stiffened Panel ◽  
Load Carrying Capacity ◽  
Stiffened Panels ◽  
Load Carrying ◽  
Stress And Deformation ◽  
The Impact ◽  
Residual Stress And Deformation

In case of ship accidents, the ship’s hull will inevitably suffer from damages such as holes, cracks, dent etc., which will threaten the structural safety of ship. It is essential to study the ultimate strength of damaged ships in order to facilitate the decision-making process of ship salvage. There are considerable publications on the subject, however, the impact of the induced residual stress and deformation are normally excluded in those studies. This paper therefore aims at investigating the effect of the impact induced residual stress and deformation on the ultimate strength of a stiffened panel through application of a nonlinear Finite Element Analysis (FEA) method. Firstly, a literature review on ultimate strength of damaged ships is presented. Secondly, a nonlinear numerical simulation is adopted to investigate the ultimate strength of stiffened panels accounting for residual stress and deformation. this procedure consists of two stages: the impact stage and the static stage. The results of the numerical simulation of both stages are validated through the results of experiments and simulations available in literature. Afterwards, a series of case studies are performed deploying the validated numerical method. Finally, a closed form expression to predict the ultimate strength accounting for impact induced residual stress and deformation is proposed based on direct simulation. Results show that the combined effect of impact induced residual stress and deformation can significantly reduce structures’ load carrying capacity. The maximum reduction ratio reaches 37% in local stiffened panel. The method of removal of all the plastic deformation area is generally too conservative to predict the ultimate strength of a damaged local stiffened panel, which will underestimate the residual load carrying capacity of ships considerably.

Influence of Yield Strength Variability over Cross-Section to Steel Beam Load-Carrying Capacity

2005 ◽  
Vol 10 (2) ◽  
pp. 151-160 ◽  
Author(s):  
J. Kala ◽  
Z. Kala
Keyword(s):  
Yield Strength ◽  
Cross Section ◽  
Carrying Capacity ◽  
Bending Moment ◽  
Statistical Characteristics ◽  
Load Carrying Capacity ◽  
Load Carrying ◽  
Strength Variability ◽  
Hot Rolled ◽  
Hot Rolled Steel

Authors of article analysed influence of variability of yield strength over cross-section of hot rolled steel member to its load-carrying capacity. In calculation models, the yield strength is usually taken as constant. But yield strength of a steel hot-rolled beam is generally a random quantity. Not only the whole beam but also its parts have slightly different material characteristics. According to the results of more accurate measurements, the statistical characteristics of the material taken from various cross-section points (e.g. from a web and a flange) are, however, more or less different. This variation is described by one dimensional random field. The load-carrying capacity of the beam IPE300 under bending moment at its ends with the lateral buckling influence included is analysed, nondimensional slenderness according to EC3 is λ¯ = 0.6. For this relatively low slender beam the influence of the yield strength on the load-carrying capacity is large. Also the influence of all the other imperfections as accurately as possible, the load-carrying capacity was determined by geometrically and materially nonlinear solution of very accurate FEM model by the ANSYS programme.

Sign in / Sign up

Export Citation Format

Share Document