Impact of Water on the Fatigue Performance of Large-Scale Grouted Connection Tests

2016 ◽  
Author(s):  
Peter Schaumann ◽  
Alexander Raba ◽  
Anne Bechtel
Keyword(s):  
Large Scale ◽  
Fatigue Tests ◽  
Fatigue Performance ◽  
Small Scale ◽  
Test Results ◽  
Ambient Conditions ◽  
Research Project ◽  
Joint Research Project ◽  
Scale Test ◽  
The Impact

Grouted connections represent a common joining technique between substructure and foundation piles of offshore oil & gas platforms as well as of offshore wind turbines. Due to cyclic loads arising from wind and wave actions the fatigue performance of the connection has to be considered. In lattice substructures like jackets the grouted connections are located at seabed level being fully submerged during their entire lifetime. Today’s fatigue design regulations are based on investigations neglecting any influence of the surrounding water since they were conducted in dry ambient conditions. So far, only Germanischer Lloyd gives additional recommendations for submerged grouted connections. At the Institute for Steel Construction, Leibniz Universität Hannover, Germany investigations of the joint research project ‘GROWup’ focus on the fatigue performance of axially loaded grouted connections. The project is funded by the Federal Ministry for Economic Affairs and Energy (BMWi, funding sign: 0325290) and is the third project in a row dealing with grouted connections. As part of this research project, cyclic loading tests on small-scale and large-scale grouted connections with shear keys are conducted. Small-scale fatigue tests showed a reduced number of endurable load cycles for connections when tested in wet ambient conditions. However, the transferability of these findings to a larger scale was still doubtful due to unknown scale effects. Therefore, the impact of water on the fatigue performance was tested recently at large-scale grouted connections. Previous to the submerged large-scale grouted connection fatigue tests, similar test specimens were exposed to alternating loads at dry ambient conditions. Comparison of both large-scale test results under wet and dry conditions enable to estimate the influence of water on the fatigue performance of grouted connections. Reflection of the small-scale test results gives hints on the scale effect. Test preparation, test results and design recommendations are presented in the paper.

Effects of Attrition due to Water in Cyclically Loaded Grouted Joints

2014 ◽  
Author(s):  
Peter Schaumann ◽  
Alexander Raba ◽  
Anne Bechtel
Keyword(s):  
Wind Farms ◽  
Fatigue Performance ◽  
Offshore Wind ◽  
Small Scale ◽  
Water Effect ◽  
Research Project ◽  
Joint Research Project ◽  
Shear Keys ◽  
The Impact ◽  
Water Depths

According to political goals, electricity from offshore wind farms in Germany will amount to 15 GW by 2030. Most of the wind farms will be located far offshore in water depths larger than 30 m. For such water depths, lattice substructures like jackets or tripods are the preferred solution. The substructures are founded on piles and connected to these by submerged grouted joints. In lattice substructures grouted joints are predominantly loaded by cyclic axial loads. Even though, this connection is well known from the offshore oil and gas industry, comparatively few results on effects of attrition due to water for grouted joints are available. At the Institute for Steel Construction of the Leibniz University Hannover, Germany, within the joint research project ‘GROWup’ investigations focus on the fatigue performance of grouted joints under predominant axial loading. As part of this research project, cyclic loading tests on small scale grouted joints with shear keys were conducted. The specimens were filled with industrial grout products and tested in a water basin to evaluate the influence of water to the fatigue performance of the connection at small scale. These test results show that the water effect leads to a significant reduction of the fatigue performance of the connection compared to results from tests in dry conditions. Moreover, the impact of water is proportional to the applied test frequency. The results of the structural tests differ from results of pure material specimen tests, on which current code provisions are based. This paper presents results from the small scale tests on grouted joints with shear keys in dry and submerged conditions. Effects of attrition due to water are shown and their effect is quantified. The results are compared to other published findings. In conclusion the presented investigations underline the importance of the water effect to the fatigue performance of small scale grouted joints. In conclusion, this paper will stimulate discussions on the demand for research on large- and real-scale grouted joints.

Gas and Water Permeation in Flexible Pipes

2002 ◽  
Author(s):  
Tore Roberg Andersen ◽  
Jan Ivar Skar
Keyword(s):  
Large Scale ◽  
Cold Water ◽  
Small Scale ◽  
Test Results ◽  
Test Program ◽  
Flexible Pipe ◽  
Water Permeation ◽  
Flexible Pipes ◽  
Scale Test ◽  
Temperature And Pressure

A test program has been performed to obtain the permeation coefficients for methane, carbon dioxide and water in PVDF. Small-scale tests showed that water is transported through the PVDF inner sheath of the flexible pipes, and into the annulus. A large-scale test was carried out to verify the small-scale test results. It was performed in a 2″ flexible pipe with length 3 m. The bore temperature and pressure were 100°C and 50 bar, respectively. The pipe was submerged in cold water in order to get a correct temperature gradient in the pipe. The test showed that the annulus of flexible pipe with PVDF inner sheath would become water wet due to permeation, depending upon the bore and annulus conditions.

scholarly journals Pengembangan Buku Ajar Perkoperasian Indonesia Dalam Perkuliahan Mahasiswa Prodi Pendidikan Ekonomi

2020 ◽  
Vol 4 (2) ◽  
pp. 243-252
Author(s):  
Putri Vina Sefaverdiana ◽  
Melisa Wahyu Fandyansari
Keyword(s):  
Research And Development ◽  
Student Learning ◽  
Large Scale ◽  
Small Scale ◽  
Development Research ◽  
Test Results ◽  
Scale Test ◽  
Improve Student Learning

Indonesian Cooperative textbooks are development research aimed at developing quality textbooks and can effectively improve understanding of existing cooperatives in Indonesia. Textbooks as a support in Cooperative lectures, in order to improve student learning in class so that students have understanding and skills in cooperating. The purpose of this textbook is to make it easier for students to learn and understand as a provision for students to develop cooperatives in their respective areas of residence. The method in this research is a research and development research using a model from Dick and Carrey. The test results obtained from the first material expert were 84.5%, the second material expert obtained 76.4%. 3%. After the expert test was carried out a small-scale test where the result was 82.6% and the large-scale test obtained a result of 86.3%. From the results of the percentage, it states that the textbook is in the good category and is feasible to apply

Effect of Welding Residual Stress on Fatigue Performance of the Welded Joints Treated by Ultrasonic Peening

2011 ◽  
Vol 418-420 ◽  
pp. 337-341 ◽  
Author(s):  
Liang Chen Wu ◽  
Dong Po Wang
Keyword(s):  
Residual Stress ◽  
Performance Improvement ◽  
Welded Joints ◽  
Large Scale ◽  
Stress Relief ◽  
Fatigue Tests ◽  
Welding Residual Stress ◽  
Fatigue Performance ◽  
Test Results ◽  
Ultrasonic Peening

The fatigue tests of Q235B steel unload longitudinal fillet welded joints containing high welding residual stress were carried out. And the effect of welding residual stress on fatigue performance of the welded joints treated by ultrasonic peening has been studied. Specimens were divided into four groups: as welded, specimens treated by ultrasonic peening(UP), specimens treated by stress relief treatment(SRT) and specimens treated by both ultrasonic peening and stress relief treatment(UP+SRT). Test results show that the effect on fatigue performance of the welded joints treated by ultrasonic peening from welding residual stress is small. It is safe that using the small specimens treated by ultrasonic peening and not containing high welding residual stress to appraise the fatigue performance improvement on large-scale welded structures which are as the same junction style and thickness as the small.

scholarly journals TAHAP PENGEMBANGAN BAHAN AJAR “CREATIVE FACTOR” BERBASIS PROYEK PADA MATERI KELIPATAN DAN FAKTOR BILANGAN DIKELAS IV SEKOLAH DASAR

2020 ◽  
Vol 1 (1) ◽  
Author(s):  
Ina Riana ◽  
Rida Fironika Kusumadewi ◽  
Nuhyal Ulia
Keyword(s):  
Large Scale ◽  
Average Score ◽  
Small Scale ◽  
Teaching Material ◽  
Development Research ◽  
Test Results ◽  
Student Responses ◽  
Research Procedure ◽  
Scale Test ◽  
Teacher Responses

Abstrak. This research is to develop and find out the feasibility of "Creative Factor" teaching material products on multiples and number factors. "Creative Factor" teaching material products multiples and number factors are developed based on the teacher's need for other reference sources in learning. This research uses the Research and Development (RnD) method. The development of "Creative Factor" teaching material products uses a development research procedure according to Sugiyono that contains 10 thrones. Based on this, the research results obtained include: (1) the validation results from 4 experts obtained an average score of 84 and a percentage of 90% with the criteria "Very Eligible". (2) the results of the small-scale test get teacher responses obtained by the percentage of 88% with the criteria "Very Practical". While the results of student responses obtained 97.2% percentage "Very Practical". (3) large-scale test results obtained by teacher responses obtained by the percentage of 90% with the criteria "Very Practical". While the results of student responses obtained 96% percentage "Very Practical". Based on these results, the development of "Creative Factor" teaching material products can be declared worthy to be used as a companion in the learning process.

scholarly journals Climate SPHINX: evaluating the impact of resolution and stochastic physics parameterisations in the EC-Earth global climate model

2017 ◽  
Vol 10 (3) ◽  
pp. 1383-1402 ◽  
Author(s):  
Paolo Davini ◽  
Jost von Hardenberg ◽  
Susanna Corti ◽  
Hannah M. Christensen ◽  
Stephan Juricke ◽  
...  
Keyword(s):  
High Resolution ◽  
Large Scale ◽  
Climate Model ◽  
Global Climate ◽  
Rainfall Variability ◽  
Global Climate Model ◽  
Small Scale ◽  
Low Resolution ◽  
The Impact ◽  
Stochastic Physics

Abstract. The Climate SPHINX (Stochastic Physics HIgh resolutioN eXperiments) project is a comprehensive set of ensemble simulations aimed at evaluating the sensitivity of present and future climate to model resolution and stochastic parameterisation. The EC-Earth Earth system model is used to explore the impact of stochastic physics in a large ensemble of 30-year climate integrations at five different atmospheric horizontal resolutions (from 125 up to 16 km). The project includes more than 120 simulations in both a historical scenario (1979–2008) and a climate change projection (2039–2068), together with coupled transient runs (1850–2100). A total of 20.4 million core hours have been used, made available from a single year grant from PRACE (the Partnership for Advanced Computing in Europe), and close to 1.5 PB of output data have been produced on SuperMUC IBM Petascale System at the Leibniz Supercomputing Centre (LRZ) in Garching, Germany. About 140 TB of post-processed data are stored on the CINECA supercomputing centre archives and are freely accessible to the community thanks to an EUDAT data pilot project. This paper presents the technical and scientific set-up of the experiments, including the details on the forcing used for the simulations performed, defining the SPHINX v1.0 protocol. In addition, an overview of preliminary results is given. An improvement in the simulation of Euro-Atlantic atmospheric blocking following resolution increase is observed. It is also shown that including stochastic parameterisation in the low-resolution runs helps to improve some aspects of the tropical climate – specifically the Madden–Julian Oscillation and the tropical rainfall variability. These findings show the importance of representing the impact of small-scale processes on the large-scale climate variability either explicitly (with high-resolution simulations) or stochastically (in low-resolution simulations).

Analytical Model for Rockfall Protection Galleries - a Blind Prediction of Test Results and Conclusion

2011 ◽  
Vol 82 ◽  
pp. 722-727 ◽  
Author(s):  
Kristian Schellenberg ◽  
Norimitsu Kishi ◽  
Hisashi Kon-No
Keyword(s):  
Degrees Of Freedom ◽  
Large Scale ◽  
Test Results ◽  
Blind Prediction ◽  
Proposed Model ◽  
Input Parameters ◽  
Scale Test ◽  
Definition Of ◽  
Protective Structures ◽  
Cushion Layer

A system of multiple degrees of freedom composed out of three masses and three springs has been presented in 2008 for analyzing rockfall impacts on protective structures covered by a cushion layer. The model has then been used for a blind prediction of a large-scale test carried out in Sapporo, Japan, in November 2009. The test results showed substantial deviations from the blind predictions, which led to a deeper evaluation of the model input parameters showing a significant influence of the modeling properties for the cushion layer on the overall results. The cushion properties include also assumptions for the loading geometry and the definition of the parameters can be challenging. This paper introduces the test setup and the selected parameters in the proposed model for the blind prediction. After comparison with the test results, adjustments in the input parameters in order to match the test results have been evaluated. Conclusions for the application of the model as well as for further model improvements are drawn.

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 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 Geographical and logistical factors of sustainable development of rural tourism in the context of regional economy

2016 ◽  
pp. 9-14
Author(s):  
I. Smyrnov
Keyword(s):  
Sustainable Development ◽  
Large Scale ◽  
Regional Economy ◽  
Local Economy ◽  
Rural Tourism ◽  
Small Scale ◽  
Resource Base ◽  
Tourist Flows ◽  
Definition Of ◽  
The Impact

Rural tourism is now seen as an important direction of development of the regional economy. From the perspective of sustainable development rural tourism affects the economic, social and environmental aspects of the regional and local economy. Rural tourism is closely linked with agrotourism, eco-tourism, natural tourism and so on. Sustainable rural tourism can be realized by applying logistic, geographic and marketing approaches as components of sustainable development strategies. Logistics approach is determined by logistic potential of resource base of rural tourism and appropriate tourist flows regulation. In this context in the article the concept of tourism capacity or capacity of the resource base of rural tourism is used. The problem of the definition of tourism pressure on the resource base of rural tourism, particularly in natural landscapes is disclosed. Unlike environmental and recrealogical sciences, which stop at the capacity definition of the resource base of tourism, tourism logistics compares this figure with the existing tourist flows and accordingly determines the safe way of tourism management to ensure its sustainable nature. It was shown that these strategies boil down to two basic types – the further development of tourism in a particular area or limit such activities to conserve the resource base of tourism. Recreational (travel) load is the indicator that reflects the impact of tourism on the resource base of tourism (especially landscape complex), expressed by the number of tourists or tourists-days per area unit or per tourist site for the certain period of time (day, month, season year). There are actual, allowable (the maximum) and destructive (dangerous) types of travel load. The latter can lead recreational area or resource base of rural tourism to destruction. Thus, depending on the intensity of tourism resource base using in rural tourism it may change – according to tourist consumption. Large number of tourists affects the entire range of recreational destinations and their individual components. The most vulnerable part of the environment in this sense is vegetation, except that significant changes may occur with soil, water bodies, air and so on. The geographic dimension of the problem of rural tourism sustainable development includes the concept of zoning, ie the division of the territory, offering to develop rural tourism in several zones with different modes of travel usage – from a total ban (in protected areas) for complete freedom with transitional stages, involving various limit degrees in the development of rural tourism. Marketing approach reflects the application of the curve R. Butler to the stages of development of rural tourism destinations with the release of such steps as: research, involvement, development, consolidation, stagnation (also called “saturation”), revival or decline. Shown the models that link the stage of resource base tourist development (under “Curve Butler”), strength of tourism consumption the magnitude of such effects (eg weak (disperse) impact in large scale, strong (concentrated) impact in large scale, strong (concentrated) impact in small scale, weak (disperse) impact in small scale), dynamics of tourism development at the territory.

Sign in / Sign up

Export Citation Format

Share Document