Effect of variation of the loading direction on the displacement accumulation of large-diameter piles under cyclic lateral loading in sand

2014 ◽  
Vol 51 (10) ◽  
pp. 1196-1206 ◽  
Author(s):  
Christina Rudolph ◽  
Britta Bienen ◽  
Jürgen Grabe
Keyword(s):  
Large Diameter ◽  
Offshore Structures ◽  
Simple Approach ◽  
Lateral Loading ◽  
Small Scale ◽  
Centrifuge Test ◽  
Test Results ◽  
Loading Direction ◽  
Stress Levels ◽  
Transverse Movement

Foundation piles supporting offshore structures experience cyclic lateral loading arising from waves and wind, which are not typically uni-directional over the lifetime of the structure. This paper presents results from centrifuge experiments in sand, representing a large diameter prototype tested at stress levels similar to the field subjected to cyclic lateral loading from varying directions. The results demonstrate increased deformation accumulation due to the changing loading direction, compared to the uni-directional case. Displacement accumulation is not limited to the main loading direction but includes transverse movement as well. Similar trends were observed in small-scale 1g modelling that allowed a larger number of load cycles to be applied. The centrifuge test results provide confidence of the applicability of the findings to the prototype. Current methods that neglect the effect of variation of the loading direction will provide predictions of displacement accumulation of piles that are un-conservative. Therefore, a simple approach is proposed here to estimate the augmentation of displacement accumulation due to variation in loading direction compared to the uni-directional case.

scholarly journals CENTRIFUGE MODELING OF LARGE DIAMETER UNDERGROUND PIPES SUBJECTED TO HEAVY TRAFFIC LOADS

2016 ◽  
Vol 16 (3) ◽  
pp. 31-46
Author(s):  
B Rakitin ◽  
◽  
X Ming
Keyword(s):  
Soil Cover ◽  
Heavy Traffic ◽  
Large Diameter ◽  
Initial Stresses ◽  
Centrifuge Test ◽  
Test Results ◽  
Traffic Loading ◽  
Cover Depth ◽  
Traffic Loads ◽  
Heavy Truck

impose uncertainties on pipe design. This paper describes the procedure and results of a series of geotechnical centrifuge tests performed on a large 1400 mm-diameter reinforced concrete pipe with a footing subjected to heavy traffic loading. The influence of soil cover depth, as well as the positions and magnitude of traffic loads, on the bending moments of the pipe were investigated. A heavy truck with a maximum load of 850 kN was simulated in the majority of the tests, and a medium truck of 252 kN was also simulated. The centrifuge test results were found to be in reasonable agreement with those from full-scale tests. The pipe would experience the most unfavorable conditions when the heaviest axis of the traffic vehicle was located directly above the pipe crown. A deeper soil cover would lead to higher initial stresses in the pipe, as well as reduced influence of traffic load. However, even for a soil cover depth of 4 m, there is significant bending moment induced by the heavy truck loading, which could not be ignored during the pipeline design. Comparison was made between the centrifuge test results and several widely adopted design methods, and unconservative calculation results were noticed for large diameter rigid pipes lying at a shallow soil cover depth subjected to heavy traffic loading.

Centrifuge modeling of large-diameter underground pipes subjected to heavy traffic loads

2014 ◽  
Vol 51 (4) ◽  
pp. 353-368 ◽  
Author(s):  
Boris Rakitin ◽  
Ming Xu
Keyword(s):  
Soil Cover ◽  
Heavy Traffic ◽  
Large Diameter ◽  
Traffic Load ◽  
Initial Stresses ◽  
Centrifuge Test ◽  
Test Results ◽  
Traffic Loading ◽  
Cover Depth ◽  
Traffic Loads

Large-diameter pipes, as well as heavy vehicles, have become increasingly prevalent, which imposes uncertainties on pipe design. This paper describes the procedure and results of a series of geotechnical centrifuge tests performed on a large 1400 mm diameter reinforced concrete pipe subjected to heavy traffic loading up to 850 kN. The influence of soil cover depth, as well as the positions and magnitude of traffic loads, on the bending moments of the pipe were investigated. The centrifuge test results were found to be in reasonable agreement with those from full-scale tests. The pipe would experience the most unfavorable conditions when the heaviest axle of the traffic vehicle was located directly above the pipe crown. A deeper soil cover would lead to higher initial stresses in the pipe, as well as reduced influence of traffic load. However, even for a soil cover depth of 4 m, there is significant bending moment induced by the heavy truck loading, which cannot be ignored during pipeline design. A comparison was made between the centrifuge test results and several widely adopted design methods, and unconservative calculation results were noticed for large-diameter rigid pipes lying at a shallow soil cover depth subjected to heavy traffic loading.

Launching of Ships and Floating Structures from Horizontal Berth by Tipping Table

1998 ◽  
Vol 14 (04) ◽  
pp. 265-276
Author(s):  
Ivo Senjanovic
Keyword(s):  
Structural Dynamics ◽  
Review Paper ◽  
Offshore Structures ◽  
Model Tests ◽  
Full Scale ◽  
Strength Analysis ◽  
Test Results ◽  
Floating Structures ◽  
Measurement Results

This review paper covers extensive investigations which were undertaken in order to verify the idea of launching of ships and other floating structures from a horizontal berth by a set of turning pads. This includes structural dynamics during launching, model tests and strength analysis of the structure and the launching system. The most important results, which were used for the design of the launching system, are presented. The preparation of a barge for side launching is described, and the full-scale measurement results are compared with the test results. The advantages of building ships and offshore structures on a horizontal berth are pointed out in the conclusion.

scholarly journals Cyclic behavior of GFRP strengthened infilled RC frames with low and normal strength concrete

2019 ◽  
Vol 26 (1) ◽  
pp. 30-42 ◽  
Author(s):  
Mehmet Emin Arslan ◽  
Ahmet Durmuş ◽  
Metin Hüsem
Keyword(s):  
Lateral Loading ◽  
Cyclic Behavior ◽  
Test Results ◽  
Normal Strength Concrete ◽  
Strength Concrete ◽  
Rc Frames ◽  
Load Carrying ◽  
Concrete Blocks ◽  
Normal Strength ◽  
Infilled Rc Frames

AbstractThis paper presents the experimental behavior of plane, non-strengthened and glass fiber reinforced polymer (GFRP) strengthened infilled reinforced concrete (RC) frames with low strength concrete (LSC) and normal strength concrete (NSC) under lateral reversed cyclic loading. For this purpose, eight full-scale, one-bay, one-storey plane and infilled (brick and aerated concrete blocks which are commonly used in RC construction) RC frames with LSC and NSC were produced and in-plane lateral loading tests were carried out. Test results indicate that infill walls considerably change the behavior of frames by increasing rigidity and load carrying capacity. By contrast, GFRP fabric used for strengthening of infilled RC frames improves ductility, load carrying and energy dissipation capacity of infilled frames with LSC and NSC as well. After all the test results were evaluated together, a GFRP strengthened brick infilled frame demonstrated the best performance under cyclic lateral loading.

scholarly journals Illumination Normalization Algorithm Combination Analysis in Face Recognition

2017 ◽  
Vol 9 (3) ◽  
pp. 334-339
Author(s):  
Rokas Semėnas
Keyword(s):  
Face Recognition ◽  
Large Scale ◽  
Real Life ◽  
Direct Approach ◽  
Small Scale ◽  
Test Results ◽  
Illumination Normalization ◽  
Recognition Algorithms ◽  
Life Problems

Face recognition programs have many practical usages in various fields, such as security or entertainment. Existing recognition algorithms must deal with various real life problems – mainly with illumination. In practice, illumination normalization models are often used only for Small-scale futures extraction, ignoring Large-scale features. In this article, new and more direct approach to this problem is offered, used algorithms and test results are given.

scholarly journals Lateral Response of a Single Pile under Combined Axial and Lateral Cyclic Loading in Sandy Soil

2018 ◽  
Vol 4 (9) ◽  
pp. 1996 ◽  
Author(s):  
Muqdad Abdallah Kahribt ◽  
Jasim M. Abbas
Keyword(s):  
Lateral Displacement ◽  
Slenderness Ratio ◽  
Offshore Structures ◽  
Lateral Loading ◽  
Loading Conditions ◽  
Lateral Loads ◽  
Dense Sand ◽  
Lateral Response ◽  
Loading System ◽  
Vertical Displacements

According to practical situation, there have been limited investigations on the response of piles subjected to combined loadings especially when subjected to cyclic lateral loads. Those few studies led to contradictory results with regard to the effects of vertical loads on the lateral response of piles. Therefore, a series of experimental investigation into piles in dense sand subjected to combination of static vertical and cyclic lateral loading were conducted with instrumented model piles. The effect of the slenderness ratio (L/D) was also considered in this study (i.e. L/D= 25 and 40). In addition, a variety of two-way cyclic lateral loading conditions were applied to model piles using a mechanical loading system. One hundred cycles were used in each test to represent environmental loading such as offshore structures. It was found that under combined vertical and cyclic lateral loads the lateral displacement of piles decreased with an increase in vertical load whereas it causes large vertical displacements at all slenderness ratios. In addition, for all loading conditions the lateral, vertical (settlement and upward) displacements and bending moments increased as either the magnitude of cyclic load or the number of cycles increases. 

scholarly journals The Development of Nervous Problem Based Modulewith Character Conservation for Nervous System Materials in the Senior High School

2018 ◽  
Vol 7 (3) ◽  
pp. 298-304
Author(s):  
Reefa Qudsiya ◽  
Lisdiana Lisdiana ◽  
Nugrahaningsih WH
Keyword(s):  
Nervous System ◽  
Product Design ◽  
Large Scale ◽  
Small Scale ◽  
Test Results ◽  
Research Subjects ◽  
Teaching Materials ◽  
Valid Test ◽  
Readability Test ◽  
Positive Results

Nervous system teaching materials available in schools do not contain scientific-related content as mandated by the 2013 curriculum. In addition, teaching materials also do not contain student character reinforcement content. The purpose of this study is to develop “Nervous Problem Based Module with a  Conservation Character” as a nervous system learning supplement. This type of research is Research and Development (R&D) using ten steps, namely identification of potential and problems, data collection, product design, product design validation, product design revisions, small scale trials, product revision I, large scale trials, product revision II, and final products. The research subjects were students of class XI of SMA N 1 Bae Kudus. Nervous Problem Based Module with a  Conservation Character  tested the feasibility, readability, and effectiveness. Feasibility tests obtained very valid results. Readability test results were very valid. Test effectiveness by applying  Nervous Problem Based Module with a  Conservation Character in learning, obtained effective results and can be used in learning. The insertion of the conservation character reinforcement in the module gives positive results on the character of students. It can be concluded that “Nervous Problem Based Module with a Conservation Character” is decent and effectively applied in the nervous system learning.

scholarly journals Pengembangan Rubrik Penskoran pada Asesmen Otentik untuk Materi Volume dan Luas Balok

2020 ◽  
Vol 4 (2) ◽  
pp. 275
Author(s):  
Yunita Rochmawati Jonan
Keyword(s):  
Authentic Assessment ◽  
Student Response ◽  
Small Scale ◽  
Development Research ◽  
Test Results ◽  
Assessment Of Learning ◽  
Teachers And Students ◽  
Scoring Rubric ◽  
Large Groups ◽  
Made In

ABSTRAK Tujuan penelitian pengembangan ini adalah menghasilkan sebuah rubrik penskoran pada asesmen otentikuntuk materi volume dan luas balok yang dapat digunakan oleh guru dan siswa. Rubrik ini dibuat sesuai dengan standar penilaian dalam kurikulum 2013. Penelitian pengembangan (R&D) ini menggunakan model Borg and Gall yang terdiri dari lima tahap yaitu penelitian dan pengumpulan data awal, perencanaan, pengembangan format produk, uji coba skala kecil, revisi akhir dan penyempurnaan produk. Hasil penelitian pengembangan ini berupa rubrik penyekoran holistik dan analitik dengan nilai sangat valid sebesar 94%. Analisis dari penelitian ini adalah angket kebutuhan bagi guru dan siswa sedangkan uji coba dilakukan melalui perorangan, kelompok kecil dan kelompok besar. Sedangkan kelayakan rubrik penskoran dari penilaian oleh ahli dengan menggunakan angket uji validitas materi, hasil belajar siswa, respon siswa serta tanggapan guru pengajar. Hasil penelitian ini menunjukkan bahwa rubrik penskoran ini efektif dalam membantu memperbaiki hasil ulangan dan cukup praktis serta dapat dipergunakan untuk memberikan penilaian hasil belajar yang sesuai dengan kurikulum 2013. Kata kunci: rubrik, penskoran, asesmen otentik.   ABSTRACT The purpose of this development research is to produce a scoring rubric on an authenticity assessment for the volume and area materials that can be used by teachers and students. The rubric is made in based on the assessment standards in the 2013 curriculum. This development research (R&D) uses the Borg and Gall model consisting of five stages of preliminary data research and collection, planning, product format development, small-scale trials, final revisions and product enhancements. The results of this development research include holistic and analytic scoring rubric with a very valid score of 94%. The rubric is analyzed fromquestionnaire for teachers and students, while trials are conducted through individuals, small groups and large groups. The feasibility of the scoring rubric from assessment by members by using the material validity test questionnaire, student learning results, student response and teacher responses. The results of this study show that the scoring rubric is effective in helping to improve the test results and is practical and can be used to provide assessment of learning outcomes in accordance with the 2013 curriculum. Keywords: rubric, scoring, authentic assessment.

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