• Journal of the Korean GEO-environmental Society
• /
• 제2권4호
• /
• pp.51-61
• /
• 2001

A series of model tests and analyses by load transfer function were performed to study load-settlement behaviour with relative compaction ratio of soil and embeded depth of pile. In the model tests, embeded depth ratio(L/D) of pile were installed 15, 20, 25 and relative compaction of soil(RC) is 85%, 95% and then cement were injected at around perimeter of pile. For analysis of embedded pile, the paper were compared results of model tests with analysis results by Vijayvergiya model and Castelli model, Gwizdala model of elastic plasticity-perfect plastic model and then the fitness load transfer mechanism was proposed to predict load-settlement behaviour of embeded pile. The analysis results of predicted bearing capacity by load transfer function, ultimate bearing capacity of embeded pile were approached to measured value and behaviour of initial load-settlement curve were estimated that load transfer function by Castelli were similar to measured value. The result of axial load analysis of bored pile shows that skin friction estimated by load transfer mechanism is investigated more a little than that of measured values.

• International Journal of Concrete Structures and Materials
• /
• 제10권2호
• /
• pp.189-203
• /
• 2016

This paper investigates on the use of advanced optical measurement methods, i.e. 3D coordinate measurement machines (3D CMM) and stereo-vision digital image correlation (3D DIC), for the mechanical analysis of shear deficient prestressed concrete members. Firstly, the experimental program is elaborated. Secondly, the working principle, experimental setup and corresponding accuracy and precision of the considered optical measurement techniques are reported. A novel way to apply synthesised strain sensor patterns for DIC is introduced. Thirdly, the experimental results are reported and an analysis is made of the structural behaviour based on the gathered experimental data. Both techniques yielded useful and complete data in comparison to traditional mechanical measurement techniques and allowed for the assessment of the mechanical behaviour of the reported test specimens. The identified structural behaviour presented in this paper can be used to optimize design procedure for shear-critical structural concrete members.

• Wind and Structures
• /
• 제13권4호
• /
• pp.327-346
• /
• 2010

During the past decade, many electrical transmission tower structures have failed during downburst events. This study is a part of a research program aimed to understand the behaviour of transmission lines under such localized wind events. The present study focuses on the assessment of the dynamic behaviour of the line conductors under downburst loading. A non-linear numerical model, accounting for large deformations and the effect of pretension loading, is developed and used to predict the natural frequencies and mode shapes of conductors at various loading stages. A turbulence signal is extracted from a set of full-scale data. It is added to the mean component of the downburst wind field previously evaluated from a CFD analysis. Dynamic analysis is performed using various downburst configurations. The study reveals that the response is affected by the background component, while the resonant component turns to be negligible due large aerodynamic damping of the conductors.

• Structural Engineering and Mechanics
• /
• 제13권3호
• /
• pp.241-260
• /
• 2002

The effect of shear coupled with axial force variation on the inelastic seismic behaviour of reinforced concrete bridge piers is investigated in this paper. For this purpose, a hysteretic axial-shear interaction model was developed and implemented in a nonlinear finite element analysis program. Thus, flexure-shear-axial interaction is simulated under variable amplitude reversed actions. Comparative studies for shear-dominated reinforced concrete columns indicated that a conventional FE model based on flexure-axial interaction only gave wholly inadequate results and was therefore incapable of predicting the behaviour of such members. Analysis of a reinforced concrete bridge damaged during the Northridge (California 1994) earthquake demonstrated the importance of shear modelling. The contribution of shear deformation to total displacement was considerable, leading to increased ductility demand. Moreover, the effect of shear with axial force variation can significantly affect strength, stiffness and energy dissipation capacity of reinforced concrete members. It is concluded that flexure-shear-axial interaction should be taken into account in assessing the behaviour of reinforced concrete bridge columns, especially in the presence of high vertical ground motion.

• Structural Engineering and Mechanics
• /
• 제60권5호
• /
• pp.749-760
• /
• 2016

The objective of the study is to investigate the effects of model calibration on seismic behaviour of a historical mosque which is one of the most significant Ottomon structures. Seismic analyses of calibrated and noncalibrated numeric models were carried out by using acceleration records of Kocaeli earthquake in 1999. In numerical analysis, existing crack zones on real structure was investigated in detail. As a result of analyses, maximum stresses and displacements of calibrated and noncalibrated numerical models were compared each other. Consequently, seismic behaviour and damage state of historical masonry Hafsa Sultan mosque was determined as more realistic in the event of a severe earthquake.

• Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
• /
• 한국윤활학회 2001년도 제34회 추계학술대회 개최
• /
• pp.350-355
• /
• 2001

Minimum clearance between the piston seal groove of a piston and cylinder bore to ensure against extrusion of the piston seal and leakage of working fluids is an important design parameter for a seal designer in hydraulic cylinder application. Contact force, critical pressure at which extrusion occurs, leakage rate, fluid film thickness and friction force have been analyzed for some design parameter such as clearance between cylinder wall piston, depth of rectangular groove and pressure of sealed hydraulic fluid. In this paper, we analyze displacement and stress of ACGT seal by finite element analysis to understand Contact Behaviour Characters

• Computers and Concrete
• /
• 제15권3호
• /
• pp.373-389
• /
• 2015

The development of a finite element model for the geometric and material nonlinear analysis of bonded prestressed concrete continuous beams is presented. The nonlinear geometric effect is introduced by the coupling of axial and flexural fields. A layered approach is applied so as to consider different material properties across the depth of a cross section. The proposed method of analysis is formulated based on the Euler-Bernoulli beam theory. According to the total Lagrangian description, the constructed stiffness matrix consists of three components, namely, the material stiffness matrix reflecting the nonlinear material effect, the geometric stiffness matrix reflecting the nonlinear geometric effect and the large displacement stiffness matrix reflecting the large displacement effect. The analysis is capable of predicting the nonlinear behaviour of bonded prestressed concrete continuous beams over the entire loading stage up to failure. Some numerical examples are presented to demonstrate the validity and applicability of the proposed model.

• Advances in concrete construction
• /
• 제10권2호
• /
• pp.161-169
• /
• 2020

This paper studies the influence of silica fume and Processed Quarry Fines (PQF) on the flexural behaviour of the reinforced concrete beams by experimental as well as numerical studies. The study has been shown that the incorporation of PQF can significantly increase the stiffness and the flexural strength of reinforced HPC beams. Also, the ultimate strength of specimens prepared with the 10% silica fume and 100% PQF are higher compared to conventional reinforced concrete specimen. Numerical analysis is performed to find the ultimate strength of HPC beams to compare with experimental results. Nonlinear behaviour of steel reinforcing bars and plain concrete is simulated using appropriate constitutive models and experimental results. The results indicate that the ultimate strength, deformed shape and crack patterns of reinforced HPC beams obtained through the Finite Element Analysis (FEA) are confirming with the experimental results.

• Structural Engineering and Mechanics
• /
• 제56권3호
• /
• pp.355-367
• /
• 2015

This paper deals with a new designed joint system for single-layer spatial structures. As the stability of these structures is greatly influenced by the joint behaviour, the aim of this paper is the characterization of the joint response in bending through Finite Element Method (FEM) analysis using ABAQUS. The behaviour of the joints studied here was influenced by many geometrical factors, such as bolts and plate sizes, distance between bolts and end-plate thickness. The study comprised five models of joints with different values of those parameters. The numerical results were compared to the results of previous experimental tests and the agreement was good enough. The differences between the numerical and experimental initial stiffness are attributed to the simplifications introduced when modelling the bolt threads as well as the presence of residual stresses in the test specimens.

• Journal of the Korean GEO-environmental Society
• /
• 제18권9호
• /
• pp.11-18
• /
• 2017

Numerical analysis method for prediction of pile behaviour characteristics has widely been used in detail design process before construction because field static loading test requires high cost. However, the reliability verification of numerical analysis of result is not permitted compare with field test. In this study, to verify the numerical analysis results, pile behaviour prediction was compared with field static loading test results. For exact analysis of interaction between pile and ground, soil investigation and in-situ test such as boring, SPT and bore-hole shear test were performed before pile static loading test. During the static loading test, pile behaviour characteristics were analyzed under every loading condition. After static pile loading test, numerical analysis was carried out under same condition with static pile loading test. In the numerical analysis, to apply same loading condition with each loading condition in the field test and to compare with between the results of numerical analysis, the field test results for reliability were verified with the results of numerical analysis.