scholarly journals Uplift resistance capacity of anchor piles used in marine aquaculture

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Fukun Gui ◽  
Jianqiao Kong ◽  
Dejun Feng ◽  
Xiaoyu Qu ◽  
Fang Zhu ◽  
...  
Keyword(s):  
Failure Load ◽  
Lateral Displacement ◽  
Ccd Camera ◽  
The Body ◽  
Single Pile ◽  
Initial Tension ◽  
Marine Aquaculture ◽  
Pile Diameter ◽  
Single Piles ◽  
Uplift Resistance

AbstractAnchor piles are widely used in marine aquaculture, and the safety is largely determined by the uplift resistance capacity,especially in harsh ocean environments. However, there are few practical guides to the design and installation of the anchor piles for mooring the body of marine aquaculture equipment. Laboratory experiments were conducted to investigate the effect of the initial tension angle, pile diameter, embedded depth, and pile configuration on the uplift resistance capacity of anchor piles under oblique loads. CCD camera and load cell were utilized to measure the corresponding displacement and load, respectively. The results show that increasing the initial tension angle of circular and square single piles can significantly improve the uplift resistance capacity. The failure load of the square single pile was slightly higher than that of the circular single pile. Increasing the pile diameter can effectively improve the failure load and delay the development speed of the pile top displacement. Increasing the embedded depth can effectively improve the failure load and increase the lateral displacement of the pile top. The uplift resistance capacity of the dual anchor piles was better than that of the single anchor piles. The layout configuration has little effect on the failure load, but has a large effect on the displacement development.

scholarly journals Uplift Resistance Capacity of Anchor Piles used in Marine Aquaculture

2021 ◽  
Author(s):  
Fukun Gui ◽  
Jianqiao Kong ◽  
Dejun Feng ◽  
Xiaoyu Qu ◽  
Fang Zhu ◽  
...  
Keyword(s):  
Laboratory Experiments ◽  
Failure Load ◽  
Lateral Displacement ◽  
Single Pile ◽  
Initial Tension ◽  
Marine Aquaculture ◽  
Pile Diameter ◽  
Single Piles ◽  
Uplift Resistance ◽  
Better Than

Abstract Anchor piles are widely used in marine aquaculture, and their uplift resistance capacity largely determines their safety, especially in harsh ocean environments. However, a practical guide on its design and installation is wanting. Laboratory experiments were conducted to investigate the effect of the initial tension angle, pile diameter, embedded depth, and pile configuration on the uplift resistance capacity of anchor piles for marine aquaculture under oblique loads. The results show that increasing the initial tension angle of circular and square single piles can significantly improve the uplift resistance capacity. The failure load of the square single pile was slightly higher than that of the circular single pile. Increasing the pile diameter can effectively improve the failure load and delay the development speed of the pile top displacement. Increasing the embedded depth can effectively improve the failure load and increase the lateral displacement of the pile top. The uplift resistance capacity of the dual anchor piles was better than that of the single anchor piles. The layout configuration has little effect on the failure load, but has a large effect on the displacement development.

scholarly journals Modeling Laterally Loaded Single Piles Accounting for Nonlinear Soil-Pile Interactions

2013 ◽  
Vol 2013 ◽  
pp. 1-7 ◽  
Author(s):  
Maryam Mardfekri ◽  
Paolo Gardoni ◽  
Jose M. Roesset
Keyword(s):  
Finite Element ◽  
Lateral Displacement ◽  
Three Dimensional ◽  
Nonlinear Behavior ◽  
Soil Mass ◽  
Fe Model ◽  
The Finite Element Method ◽  
Pile Diameter ◽  
Single Piles ◽  
Laterally Loaded

The nonlinear behavior of a laterally loaded monopile foundation is studied using the finite element method (FEM) to account for soil-pile interactions. Three-dimensional (3D) finite element modeling is a convenient and reliable approach to account for the continuity of the soil mass and the nonlinearity of the soil-pile interactions. Existing simple methods for predicting the deflection of laterally loaded single piles in sand and clay (e.g., beam on elastic foundation,p-ymethod, and SALLOP) are assessed using linear and nonlinear finite element analyses. The results indicate that for the specific case considered here thep-ymethod provides a reasonable accuracy, in spite of its simplicity, in predicting the lateral deflection of single piles. A simplified linear finite element (FE) analysis of piles, often used in the literature, is also investigated and the influence of accounting for the pile diameter in the simplified linear FE model is evaluated. It is shown that modeling the pile as a line with beam-column elements results in a reduced contribution of the surrounding soil to the lateral stiffness of the pile and an increase of up to 200% in the predicted maximum lateral displacement of the pile head.

scholarly journals Study on the horizontal bearing characteristics of pile foundation in coral sand

2021 ◽  
Author(s):  
Chunyan Wang ◽  
Hanlong Liu ◽  
Xuanming Ding ◽  
Chenglong Wang ◽  
Qiang Ou
Keyword(s):  
Lateral Displacement ◽  
Experimental Studies ◽  
Deformation Characteristic ◽  
Bending Moment ◽  
Silica Sand ◽  
Pile Head ◽  
Pile Diameter ◽  
Coral Sand ◽  
Horizontal Pressure ◽  
Different Diameters

This paper presents the horizontal bearing characteristics of piles in coral sand and silica sand from comparative experimental studies. A total of 6 model piles with different diameters are tested. The horizontal bearing capacity, deformation characteristic, bending moment, p-y curve, the change in soil horizontal pressure, as well as the particle breakage behaviour of coral sand are investigated. The results show that, in coral sand foundation, the horizontal bearing capacities of piles and the increments of soil horizontal pressures are obviously greater than those in silica sand. Accordingly, the lateral displacement, the rotation of pile head, the bending moment and the corresponding distribution depth in coral sand are significantly smaller than that in silica sand. The p-y curves indicate that the horizontal stiffness of coral sand is greater than that of silica sand. Remarkably, the breakage behaviour of coral sand is mainly distributed in the range of 10 times pile diameter depth and 5 times pile diameter width on the side where the sand is squeezed by pile. Furthermore, in coral sand, the influence of pile size is more pronounced, the squeezing force generated by pile spread farther and its influence range is larger compared to those in silica sand.

Long bone cross-sectional geometry

2020 ◽  
pp. 307-320
Author(s):  
Christopher B. Ruff ◽  
Ryan W. Higgins ◽  
Kristian J. Carlson
Keyword(s):  
Mechanical Properties ◽  
Cross Sections ◽  
Lateral Displacement ◽  
Center Of Mass ◽  
Gait Pattern ◽  
Locomotor Behavior ◽  
The Body ◽  
Long Bone ◽  
Cross Sectional ◽  
Body Center

Long bone diaphyseal cross-sectional geometries reflect the mechanical properties of the bones, and can be used to aid in inferences of locomotor behavior in extinct hominins. This chapter considers all available long bone diaphyseal and femoral neck cross-sections of specimens from Sterkfontein Member 4, and presents comparisons of these section properties and other cross-sectional dimensions with those of other early hominins as well as modern samples. The cross-sectional geometry of the Sterkfontein Member 4 long bone specimens suggests some similarities to, but also interesting differences in, mechanical loading of these elements relative to modern humans. The less asymmetric cortical bone distribution in the Sterkfontein femoral necks is consistent with other evidence above indicating an altered gait pattern involving lateral displacement of the body center of mass over the stance limb. The relatively very strong upper limb of StW 431 implies that arboreal behavior formed a significant component of its locomotor repertoire. Bipedal gait may have been less efficient and arboreal climbing more prevalent in the Sterkfontein hominins.

scholarly journals Features of histological changes in the lungs of mature animals under conditions of hyperhomocysteinemia

2019 ◽  
pp. 32-37
Author(s):  
І. А. Samborska ◽  
O. Ye. Маievskyi ◽  
Z. M. Nebesna
Keyword(s):  
Ccd Camera ◽  
The Body ◽  
Male Rats ◽  
Experimental Simulation ◽  
Chronic Obstructive ◽  
Adult Rats ◽  
Histological Changes ◽  
Obstructive Pulmonary Disease ◽  
Vascular Walls ◽  
Inflammatory Infiltrates

Hyperhomocysteinemia is a well-known risk factor for atherosclerosis, coronary heart disease, stroke, and venous thrombosis. However, in recent decades, the range of diseases associated with elevated homocysteine levels has expanded significantly. The influence of this amino acid on the occurrence and development of pathologies of the respiratory system, in particular, chronic obstructive pulmonary disease, bronchial asthma, lung and pleural cancer, is currently being actively studied. The aim of the study is to find the features of histological changes in the lungs of adult rats under conditions of hyperhomocysteinemia. The experimental study was performed on 22 white nonlinear adult (6-8 months) male rats. During the experiment, the animals were divided into two groups – control and experimental. Simulation of the state of persistent hyperhomocysteinemia was achieved by administering to rats the experimental group of thiolactone homocysteine at a dose of 200 mg/kg body weight intragastrally for 60 days. Histological specimens were studied using an SEO CCAN light microscope and photo-documented using a Vision CCD Camera with an image output system from histological specimens. Histological examinations of the lungs of adult animals under conditions of hyperhomocysteinemia revealed adaptive-compensatory and destructive changes in the components of the organ. Discirculatory disorders, remodeling of the bronchial wall with the formation of inflammatory infiltrates in them were revealed. Significant areas of dys- and atelectasis and emphysematically altered areas of the parenchyma were found in the respiratory tract of the lungs. In the alveolar septa, peribronchially and paravasally, histo- and leukocyte infiltration, formation of inflammatory conglomerates were determined. Remodeling of vascular walls, especially the microcirculatory tract leads to disruption of blood supply to the body and hypoperfusion of lung tissue.

scholarly journals ANALISIS DISPLACEMENT PADA TIANG TUNGGAL DENGAN MENGGUNAKAN METODE PUSHOVER ANALYSIS

2020 ◽  
Vol 3 (2) ◽  
pp. 349
Author(s):  
Pieter Kristianto Syafrin ◽  
Chaidir Anwar Makarim ◽  
Amelia Yuwono
Keyword(s):  
Soft Soil ◽  
Pushover Analysis ◽  
Lateral Force ◽  
Pile Foundations ◽  
Engineering System ◽  
Single Pile ◽  
Drift Ratio ◽  
Single Piles ◽  
Definition Of ◽  
Capacity Method

All construction that is engineered and built rests on the ground must be supported by foundation. Foundation is the lowest part of structure that is done first and has important function in the construction of a building to continue the burden on the structure which will then be forwarded to the soil below. The term upper structure is generally used to describe part of an engineering system that carries a burden on the foundation or bottom structure. On the basis of the definition of this foundation, it can be explained that foundation is the most important part of the engineering system. (Bowles, 1991). Single pile foundations can be used on various types of soil and one of them is soft soil. To analyze elastic and non-elastic single piles in the condition of free heads and fixed heads in various dimensions, they were designed according to SNI 1726: 2012 and evaluated using the spectrum capacity method regulated in ATC-40. Based on the results of the study, a pile drift ratio and performace point values will be obtained which describe the behavior of the pile due to gradual lateral force. Results obtained describe the behavior of all the single pile models analyzed. AbstrakSemua konstruksi yang direkayasa dan dibangun bertumpu di tanah harus ditopang oleh fondasi. Fondasi adalah bagian terendah dari struktur yang dikerjakan terlebih dahulu dan memiliki fungsi penting dalam pembangunan sebuah bangunan untuk meneruskan beban struktur di atasnya yang kemudian akan diteruskan ke tanah dan bebatuan yang berada di bawah. Istilah struktur atas umumnya digunakan untuk menggambarkan bagian dari sistem rekayasa yang membawa beban pada pondasi atau struktur bawah. Atas dasar definisi yayasan ini, dapat dijelaskan bahwa yayasan adalah bagian terpenting dari sistem teknik. (Bowles, 1991). Fondasi tiang tunggal dapat digunakan pada berbagai jenis tanah dan salah satunya adalah tanah lunak. Untuk dapat menganalisis tiang tunggal elastis dan tidak elastis dalam kondisi kepala bebas dan kepala tetap dalam berbagai dimensi, mereka dirancang berdasarkan SNI 1726: 2012 dan dievaluasi menggunakan metode kapasitas spektrum yang diatur dalam ATC-40. Berdasarkan hasil penelitian, akan diperoleh suatu nilai pile drift ratio dan performace point yang menggambarkan perilaku tiang akibat diberikan gaya lateral secara bertahap.. Hasil yang diperoleh menggambarkan perilaku semua pemodelan tiang tunggal yang dianalisis.

scholarly journals Model Test and Numerical Simulation of Single Pile Response under Combined Loading in Slope

2020 ◽  
Vol 10 (17) ◽  
pp. 6140
Author(s):  
Jianwei Zhang ◽  
Xiaoju Wang ◽  
Hao Wang ◽  
Hongyu Qin
Keyword(s):  
Numerical Simulation ◽  
Model Test ◽  
Lateral Displacement ◽  
Slope Angle ◽  
Combined Loading ◽  
Single Pile ◽  
Soil Pressure ◽  
Foundation Design ◽  
Sloping Ground ◽  
Horizontal Thrust

Vertical loads are commonly transferred by piles primarily in the upper structures. However, lateral loads are also significant compared with vertical loads in pile foundation design. Compared with a pile on level ground, there are many particular characteristics in a pile that is on sloping ground. These characteristics depend on the combined loading and the magnitude of the soil lateral displacement. In order to investigate the pile’s bearing characteristics, a model test was conducted and ABAQUS software was adopted to conduct 3D numerical simulation of a single pile with different slope angles under combined loads. The experimental results indicated that (1) the soil pressure along the slope direction was smaller than the other side, resulting in an asymmetry of the slope soil around the pile, and in turn introducing a horizontal thrust to the pile; (2) with the increase of slope angle, the horizontal thrust increased while the single pile’s bearing capacity decreased; (3) the vertical load caused more pile horizontal displacement with the growth of slope angle; and (4) the pile’s moment and the displacement also increased with the growth of the slope angle. The findings in this study can provide a useful reference in the design of piles or anti-slide piles in sloping ground.

scholarly journals Tests on Model Piled Rafts in Sand: Measured Settlements Compared with Finite Element Predictions

2021 ◽  
Author(s):  
Joshua Omer ◽  
Hasan Haroglu
Keyword(s):  
Finite Element ◽  
Load Transfer ◽  
Strain Gauges ◽  
Valuable Insight ◽  
Finite Element Program ◽  
Soil Stiffness ◽  
Piled Raft ◽  
Pile Diameter ◽  
Element Program ◽  
Single Piles

AbstractLaboratory tests were carried out on non-piled rafts, single piles, surface contacting and non surface-contacting piled rafts which were made of aluminum and instrumented with strain gauges and deflection gauges. The foundations were installed in dry sand contained in a large metal tank to minimize boundary effects. Maintained loads were applied to each foundation until failure was closely approached. In parallel, analyses were performed using PLAXIS™ 3-D finite element program to compare the calculated and measured load-settlement trends hence assess the influence of soil stiffness on the foundation behaviour. The results confirmed that group efficiency of non-surface contacting piled increased with increasing pile–pile spacing and approached unity at a spacing equivalent to 8D (D = pile diameter). The data obtained from the strain gauges provided valuable insight into the load-transfer characteristics of different foundations and subsequently proved that the capacity of a surface contacting piled raft is significantly enhanced compared to that of either a non-piled raft or a non-surface contacting piled raft.

scholarly journals Multispectral Bioluminescence Tomography: Methodology and Simulation

2006 ◽  
Vol 2006 ◽  
pp. 1-7 ◽  
Author(s):  
Alexander X. Cong ◽  
Ge Wang
Keyword(s):  
Numerical Study ◽  
Wide Spectrum ◽  
Small Animal ◽  
Ccd Camera ◽  
The Body ◽  
Infrared Range ◽  
Target Cells ◽  
Bioluminescence Tomography ◽  
Multispectral Data ◽  
Spectral Bands

Bioluminescent imaging has proven to be a valuable tool for monitoring physiological and pathological activities at cellular and molecular levels in living small animals. Using biological techniques, target cells can be tagged with reporters encoding several kinds of luciferase enzymes, which generate characteristic photons in a wide spectrum covering the infrared range. Part of the diffused light can reach the body surface of the small animal, be separated into several spectral bands using appropriate filters, and collected by a sensitive CCD camera. Here we present a bioluminescence tomography (BLT) method for a bioluminescent source reconstruction from multispectral data measured on the external surface, and demonstrate the advantages of multispectral BLT in a numerical study using a heterogeneous mouse chest phantom. The results show that the multispectral approach significantly improves the accuracy and stability of the BLT reconstruction even if the data are highly noisy.

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