scholarly journals Study on Soil Displacement Fields around the Expanded Body of Drill-Expanded Concrete Piles Based on DIC Technique

2021 ◽  
Vol 11 (19) ◽  
pp. 9097
Author(s):  
Lina Xu ◽  
Haoyun Deng ◽  
Lei Niu ◽  
Yongmei Qian ◽  
Daohan Song
Keyword(s):  
Numerical Simulation ◽  
Model Test ◽  
Displacement Field ◽  
Horizontal Displacement ◽  
Image Correlation ◽  
Burial Depth ◽  
Compression Zone ◽  
Undisturbed Soil ◽  
Concrete Piles ◽  
Soil Displacement

The soil displacement field around a drill-expanded concrete pile is noticeably different from that of an equivalent section pile placed under axial load due to the mutual embedment between the expanded body and the soil. It is important to study the soil displacement field around drill-expanded concrete piles in order to understand the mechanisms of interaction between the pile and the soil. First, the model test of the half-face pile installed in undisturbed soil and the model test of the half-face pile installed in sand were used to study the soil displacement field around the pile. Then, the entire process of the soil displacement field’s formation and development under the load was observed by using digital image correlation (DIC) techniques. Finally, numerical simulation was used to verify the results of the model tests. The results show that the displacement characteristics of the soil around the pile in the undisturbed soil and sand are basically the same. There is a clear soil compression zone under the expanded body, and the magnitude and density of the displaced soil in the compression zone are much higher than in other areas. Both the vertical displacement and the horizontal displacement gradually decrease as the distance from the expanded body and the burial depth increase. The horizontal displacement of the soil under the expanded body follows a trend of first moving toward the pile body and then moving away from it. The results of the numerical simulation are basically consistent with the results of the model test, indicating that the results of the model test are relatively reliable.

scholarly journals Multiscale displacement field measurements of compressed mineral-wool samples by digital image correlation

2002 ◽  
Vol 41 (32) ◽  
pp. 6815 ◽  
Author(s):  
François Hild ◽  
Bumedijen Raka ◽  
Maud Baudequin ◽  
Stéphane Roux ◽  
Florence Cantelaube
Keyword(s):  
Digital Image Correlation ◽  
Digital Image ◽  
Displacement Field ◽  
Field Measurements ◽  
Mineral Wool ◽  
Image Correlation

Numerical Simulation of Ship Collision and Validations With Experimental Results

2021 ◽  
Author(s):  
Xiangbiao Wang ◽  
Chun Bao Li ◽  
Ling Zhu
Keyword(s):  
Numerical Simulation ◽  
Model Test ◽  
Structural Damage ◽  
Added Mass ◽  
Ship Motion ◽  
Time Dependent ◽  
Structural Deformation ◽  
Structure Interaction ◽  
Ship Collision ◽  
Good Agreement

Abstract Ship collision accidents occur from time to time in recent years, and this would cause serious consequences such as casualties, environmental pollution, loss of cargo on board, damage to the ship and its equipment, etc. Therefore, it is of great significance to study the response of ship motion and the mechanism of structural damage during the collision. In this paper, model experiments and numerical simulation are used to study the ship-ship collision. Firstly, the Coupled Eulerian-Lagrangian (CEL) was used to simulate the fluid-structure interaction for predicting structural deformation and ship motion during the normal ship-ship collision. Meanwhile, a series of model tests were carried out to validate the numerical results. The validation presented that the CEL simulation was in good agreement with the model test. However, the CEL simulation could not present the characteristics the time-dependent added mass.

Study on Similar Skills of Dynamic Model Test Concerning Fluid-Structure Interaction for Water-Conveyance Tunnel in Soft Soil

2010 ◽  
Vol 29-32 ◽  
pp. 1458-1463 ◽  
Author(s):  
Jin Yun Liu ◽  
Jian Yun Chen
Keyword(s):  
Numerical Simulation ◽  
Model Test ◽  
Structural Model ◽  
Soft Soil ◽  
Fluid Structure Interaction ◽  
Similar Relationship ◽  
Fluid Structure ◽  
Structure Interaction ◽  
Water Conveyance ◽  
Water Conveyance Tunnel

Three basic types of similar relationship between the prototype and the model for dynamic structural model test and dynamic destructive model test were proposed in corresponding literatures. At the time the situation where various similar relationships are applicable and the technique to ensure similarity for the different goal was discussed. Here the numerical simulation of model test of water-conveyance tunnel concerning fluid-structure interaction in soft soil is studied. Based on economy and practicability of selective material for model test, the similar relationship and the technique are proposed, which are validated through the example. The results of numerical simulation show: under the specific conditions, data of the model test can completely transfer to those of the prototype by use of this type of similar skill, and get more useful information. Some new ideas are introduced to keep the similarity of the hydro-structure structures.

scholarly journals MFS fading regularization method for the identification of boundary conditions from partial elastic displacement field data

2018 ◽  
Author(s):  
L. Caillé ◽  
J L. Hanus ◽  
F. Delvare ◽  
N. Michaux-Leblonda
Keyword(s):  
Inverse Problem ◽  
Boundary Conditions ◽  
Displacement Field ◽  
Regularization Method ◽  
Synthetic Data ◽  
Fundamental Solutions ◽  
Image Correlation ◽  
Method Of Fundamental Solutions ◽  
Elastic Displacement ◽  
Isotropic Elasticity

A method is proposed to solve an inverse problem in twodimensional linear isotropic elasticity. The inverse problem consists of the determination of both the entire displacement field and the boundary conditions inaccessible to the measurement from the partial knowledge of the displacement field. The algorithm is based on a fading regularization method (FRM) and is numerically implemented using the method of fundamental solutions (MFS). The inverse technique is first validated with synthetic data and is then applied to the interpretation of experimental measurements obtained by digital image correlation (DIC).

Numerical analysis of soil deformation behind the reaction wall of an open caisson induced by horizontal parallel pipe-jacking construction

2015 ◽  
Vol 52 (12) ◽  
pp. 2008-2016 ◽  
Author(s):  
Yang Sun ◽  
Jing-bo Su ◽  
Xiao-he Xia ◽  
Zheng-liang Xu
Keyword(s):  
Reaction Force ◽  
Soil Surface ◽  
Horizontal Displacement ◽  
Element Model ◽  
Deformation Analysis ◽  
Burial Depth ◽  
Maximum Displacement ◽  
Obvious Effect ◽  
Simple Loading ◽  
Pipe Jacking

The disturbance of the soil behind the reaction wall of an open caisson can affect the efficiency and safety of jacking operation and control. This study focuses on the deformation of the soil mass behind the reaction wall used to support the jack. The stress–strain relationship of the soil behind the reaction wall was analysed, providing a theoretical basis for determining the most unfavourable combination of reactive forces using a computational model. A three-dimensional finite element model for this problem was developed, and a simple loading scenario was implemented. In addition, the mechanism of the deformation of the soil induced by horizontal parallel pipe jacking was also analysed. The results showed that for the soil behind the reaction wall of the open caisson, the uplift deformation of the soil surface increased initially and later gradually decreased, eventually achieving stability. The reaction force had a relatively obvious effect on the deformation of the soil within the range of the reaction wall burial depth and the horizontal displacement of the soil along the length of the reaction wall. The maximum displacement occurred near the axis of symmetry of the reaction wall. In addition, to consider the cyclic characteristics of the reaction force, the shakedown theorem is introduced to the deformation analysis of the soil and compared with the results obtained from simple loading. It was shown that the two deformation analysis methods have certain scopes of application, depending on the individual engineering requirements.

scholarly journals Model Test and Numerical Simulation of Grouted Connections for Offshore Wind Turbine Under Static Axial Load

2020 ◽  
Vol 8 (7) ◽  
pp. 543
Author(s):  
Weiqiu Zhong ◽  
Wuxu Li ◽  
Tao Yang ◽  
Deming Liu ◽  
Lintao Li
Keyword(s):  
Numerical Simulation ◽  
Bearing Capacity ◽  
Wind Turbine ◽  
Model Test ◽  
Axial Load ◽  
Offshore Wind ◽  
Offshore Wind Turbine ◽  
Shear Keys ◽  
Better Than

The bearing capacity of the grouted connections is investigated through the model test and numerical simulation with two rates (low and high) and four kinds of specimens: shorter without shear keys, shorter with shear keys, longer with shear keys, and conical with shear keys. It reveals that the bearing characteristics of the specimen of longer with shear keys is worse than the specimen of conical with shear keys, but better than the specimen of shorter with shear keys. Moreover, the bearing characteristics of the specimen of shorter without shear keys is the worst one.

scholarly journals Experimental Investigation on Fracture Evolution in Sandstone Containing an Intersecting Hole under Compression Using DIC Technique

2019 ◽  
Vol 2019 ◽  
pp. 1-12 ◽  
Author(s):  
Hao Wu ◽  
Guoyan Zhao ◽  
Weizhang Liang ◽  
Enjie Wang ◽  
Shaowei Ma
Keyword(s):  
Fracture Behavior ◽  
Horizontal Displacement ◽  
Image Correlation ◽  
Propagation Mechanism ◽  
Shear Cracks ◽  
Compression Tests ◽  
Displacement Fields ◽  
Red Sandstone ◽  
Tensile Cracks ◽  
Dic Technique

Failure of underground structures, especially intersections, becomes more severe as the depth increases, which poses a new challenge for the safe construction and operation of deep rock engineering. To investigate the mechanical properties and fracture behavior of rock with an intersecting hole under compressive loads, a series of uniaxial compression tests was carried out on cuboid red sandstone specimens containing an intersecting hole with three types of shapes by digital image correlation (DIC) technique. The results showed that the existing hole inside specimens leads to almost a 50% reduction of mechanical parameters from that of intact ones, and this weakening effect is associated with the shapes of holes. Failure of specimens is a progressive process in which cracks, i.e., primary tensile cracks, secondary tensile cracks, and shear cracks, initiate from stress concentration zones, propagate along certain direction, and coalesce with each other into macrofractures. Both the real-time principal strain fields and horizontal displacement fields of specimens under compression could be visually displayed by DIC system, and they were in good consistency in characterizing the fracture behavior. Moreover, the propagation characteristics of primary tensile cracks were studied further by quantitatively analyzing the strain variation during the loading process, and the propagation mechanism of “open-close-reopen” of primary tensile cracks was explained in detail.

Collision Character Research for Semi-Submersible Through Model Test, Simplified Analytical and Numerical Simulation Method

2010 ◽  
Author(s):  
Zhiqiang Hu ◽  
Zhenhui Liu ◽  
Jo̸rgen Amdahl
Keyword(s):  
Numerical Simulation ◽  
Model Test ◽  
Simulation Method ◽  
Tension Force ◽  
Test Results ◽  
Buffer Effect ◽  
Mooring Lines ◽  
Column Structure ◽  
Collision Force ◽  
Energy Absorbing

The characters of the collision scenario when a semi-submersible is struck by a containership are studied in this paper, through the model test, simplified analytical method and numerical simulation. The model test is conducted in the Deepwater Offshore Basin in Shanghai Jiao Tong University. Two special devices are designed to fulfill the model test. One is Ship Launching Device, simplified as SLD, who can launch the striking ship with controllable velocity and in any horizontal direction. The other is Energy Absorbing Device, simplified as EAD, who can simulate the buffer effect of the column structure and collect the collision force as well. A numerical simulation is completed to get the approximate stiffness of the column structure, which is used to adjust the property of EAD. The motions of semi-submersible are obtained, and the collision force and the tension forces of mooring lines are also got. Collision scenario characters for semi-motion and tension force are summarized by the analysis of the model test results. The second collision phenomenon is observed. The collision force dominates the collision moment and the tension force of the mooring lines lags behind. A NTNU in-house program developed by analytical simplified method is also verified by the model test result. The comparison proves the feasibility of the program.

Sign in / Sign up

Export Citation Format

Share Document