scholarly journals Safety Assessment for Upper Part of Floating Crane Considering Minimum Luffing Angle

2021 ◽  
Vol 11 (11) ◽  
pp. 5104
Author(s):  
Min-Woo Lee ◽  
Ji-Hyun Lee ◽  
Yeon-Seung Lee ◽  
Hyun-Jin Park ◽  
Tak-Kee Lee
Keyword(s):  
Structural Analysis ◽  
Water Surface ◽  
Safety Assessment ◽  
Offshore Structures ◽  
Structural Safety ◽  
Design Criteria ◽  
Analysis Model ◽  
Work Site ◽  
Combined Stresses ◽  
Floating Crane

Floating cranes are used for the construction and installation work of harbors, various heavy industries, and offshore structures. In the case of floating cranes that need to move around the work site, their navigation can be constrained due to marine bridges. In some cases, the clearance under the bridge between the water surface and the bottom of the marine bridge may be too low, and floating cranes cannot pass under the marine bridge. In this study, the height of the marine bridges and the boom height of the floating cranes considering the minimum luffing angle were investigated. Through minimizing the boom luffing angle of the floating crane by the height of back tower, a floating crane with improved mobility through marine bridges was developed. A structural analysis model was produced to check whether the developed crane design satisfies the design criteria obeying the KR, DNVGL, and ABS rules, including luffing condition as a special consideration. As a result of the structural analyses, structural safety was validated for the service, stowage, and luffing conditions in terms of combined stresses, displacements, and buckling.

Structural Safety Assessment of a Suspension Bridge using Analysis Model Updating

2017 ◽  
Author(s):  
JunYong Park ◽  
Woong-Hee Jung ◽  
Sunjoong Kim ◽  
Ho-Kyung Kim
Keyword(s):  
Safety Assessment ◽  
Natural Frequencies ◽  
Model Updating ◽  
Dynamic Properties ◽  
Suspension Bridge ◽  
Ambient Vibration ◽  
Structural Safety ◽  
Seismic Load ◽  
Analysis Model ◽  
Design Strength

A reduction in concrete compressive strength is detected in the main tower of a suspension bridge. Since this strength is below the design strength, structural safety assessment is required. Ambient vibration tests (AVTs) were performed to identify current dynamic of the bridge with 56 dense installation point of accelerometers. Manual tuning method is applied to update analysis model based on measured dynamic properties. As a result, errors between the analysis and measurement of the natural frequencies are reduced from 9% to 4%. Automated model updating method with sensitivity-based optimization is additionally applied to update analysis model. Finally, update model has errors of natural frequencies below 2%. Utilizing the updated model, structural safety assessment is performed considering live load, wind load and seismic load.

Structural Safety Assessment of Existing Ice-Resistant Jacket Platforms in Ice Zone

2009 ◽  
Author(s):  
Dayong Zhang ◽  
Qianjin Yue ◽  
Yuan Liu ◽  
Xiaofei Che
Keyword(s):  
Safety Assessment ◽  
Failure Modes ◽  
Evaluation Criteria ◽  
Offshore Structures ◽  
Life Extension ◽  
Structural Safety ◽  
Bohai Bay ◽  
Offshore Platforms ◽  
Oil And Natural Gas ◽  
Ice Loads

Until now dozens of offshore structures have been deployed in Bohai bay since the first drilling platform was erected in 1965. The oil and natural gas resources of Bohai Bay are mainly marginal oil fields. It is necessary to build both ice-resistant and economical offshore platforms. Full-scale measurement for many years shows the design of some ice-resistant platforms is not so sophisticated, the most significant is that ice induced vibration is the main which has caused harmful accidents in Liaodong bay of Bohai. In order to ensure security operation, structural safety assessment and life extension become key problems. In this paper, failure modes of ice resist jacket platforms, the related failure evaluation criteria, and risk grade are treated. Combined with monitoring data of ice loads, assessment strategy is presented. Lastly, as an application example, safety assessments of a practical platform in Bohai Bay are carried on.

scholarly journals Model Analysis and Optimization of BIM Technology in High-rise Shear Wall Residential Structure

2019 ◽  
Vol 267 ◽  
pp. 02001
Author(s):  
Liangli Xiao ◽  
Yan Liu ◽  
Zhuang Du ◽  
Zhao Yang ◽  
Kai Xu
Keyword(s):  
Structural Analysis ◽  
Collaborative Design ◽  
Structural Model ◽  
Structural Information ◽  
Shear Wall ◽  
Structure Design ◽  
Secondary Development ◽  
Optimized Design ◽  
Analysis Model ◽  
High Rise

This study combines specific high-rise shear wall residential projects with the Revit to demonstrate BIM application processes. The use of R-Star CAD may help to realize the link barrier of the building information model and the structural analysis software PKPM. Sequentially, the information supplement of the structural analysis model is completed by extracting the structural information with the Revit secondary development. By the collaborative design platform based on BIM technology, the paper examines the collision check of structural model, conducts collision analysis on other professional models and modifies the design scheme for conflict points. After the statistics of material usage, an optimized design is proposed. The findings of this paper could contribute to provide some reference for the specific application of BIM in structural design and realize the application of BIM technology in the process of building structure design.

scholarly journals Development and Validation of a Post-Earthquake Safety Assessment System for High-Rise Buildings Using Acceleration Measurements

Mathematics ◽  
2021 ◽  
Vol 9 (15) ◽  
pp. 1758
Author(s):  
Koji Tsuchimoto ◽  
Yasutaka Narazaki ◽  
Billie F. Spencer
Keyword(s):  
Safety Assessment ◽  
Large Scale ◽  
Model Updating ◽  
Safety Evaluation ◽  
Assessment System ◽  
Shaking Table ◽  
Structural Safety ◽  
High Rise ◽  
Steel Building ◽  
Earthquake Safety

After a major seismic event, structural safety inspections by qualified experts are required prior to reoccupying a building and resuming operation. Such manual inspections are generally performed by teams of two or more experts and are time consuming, labor intensive, subjective in nature, and potentially put the lives of the inspectors in danger. The authors reported previously on the system for a rapid post-earthquake safety assessment of buildings using sparse acceleration data. The proposed framework was demonstrated using simulation of a five-story steel building modeled with three-dimensional nonlinear analysis subjected to historical earthquakes. The results confirmed the potential of the proposed approach for rapid safety evaluation of buildings after seismic events. However, experimental validation on large-scale structures is required prior to field implementation. Moreover, an extension to the assessment of high-rise buildings, such as those commonly used for residences and offices in modern cities, is needed. To this end, a 1/3-scale 18-story experimental steel building tested on the shaking table at E-Defense in Japan is considered. The importance of online model updating of the linear building model used to calculate the Damage Sensitive Features (DSFs) during the operation is also discussed. Experimental results confirm the efficacy of the proposed approach for rapid post-earthquake safety evaluation for high-rise buildings. Finally, a cost-benefit analysis with respect to the number of sensors used is presented.

Structural Safety Assessment of a 1100 TEU Container Ship, Based on a Enhanced Long Term Fatigue Analysis

2014 ◽  
Vol 1036 ◽  
pp. 935-940
Author(s):  
Leonard Domnisoru ◽  
Ionica Rubanenco ◽  
Mihaela Amoraritei
Keyword(s):  
Safety Assessment ◽  
Safety Evaluation ◽  
Irregular Waves ◽  
Structural Safety ◽  
Random Wave ◽  
Wave Loads ◽  
Strength Assessment ◽  
Integrated Method ◽  
Hydroelastic Response

This paper is focused on an enhanced integrated method for structural safety assessment of maritime ships under extreme random wave loads. In this study is considered an 1100 TEU container test ship, with speed range 0 to 18 knots. The most comprehensive criteria for ships structural safety evaluation over the whole exploitation life is based on the long term ship structures analysis, that includes: stress hot-spots evaluation by 3D/1D-FEM hull models, computation of short term ship dynamic response induced by irregular waves, long term fatigue structure assessment. The analysis is enhanced by taking into account the ships speed influence on hydroelastic response. The study includes a comparative analysis on two scenarios for the correlation between the ships speed and waves intensity. The standard constant ship speed scenario and CENTEC scenario, with total speed loss at extreme waves condition, are considered. Instead of 20 years ship exploitation life estimated by classification societies rules from the long term structural safety criteria, the enhanced method has predicted more restrictive values of 14.4-15.7 years. The numerical analyses are based on own software and user subroutines. The study made possible to have a more realistic approach of ships structural strength assessment, for elastic and faster ships as container carriers, in compare to the standard one based only on naval rules, delivering a method with higher confidence in the designed structural safety.

scholarly journals Structural safety assessment for FLNG-LNGC system during offloading operation scenario

2017 ◽  
Vol 31 (2) ◽  
pp. 192-201 ◽  
Author(s):  
Zhi-qiang Hu ◽  
Dong-wei Zhang ◽  
Dong-ya Zhao ◽  
Gang Chen
Keyword(s):  
Safety Assessment ◽  
Structural Safety

scholarly journals Multi-source data fusion method for structural safety assessment of water diversion structures

2021 ◽  
Author(s):  
Sherong Zhang ◽  
Ting Liu ◽  
Chao Wang
Keyword(s):  
Data Fusion ◽  
Safety Assessment ◽  
Evidence Theory ◽  
Weighted Average ◽  
Water Diversion ◽  
Sensor Data ◽  
Structural Safety ◽  
Fusion Method ◽  
Bhattacharyya Distance ◽  
Source Data

Abstract Building safety assessment based on single sensor data has the problems of low reliability and high uncertainty. Therefore, this paper proposes a novel multi-source sensor data fusion method based on Improved Dempster–Shafer (D-S) evidence theory and Back Propagation Neural Network (BPNN). Before data fusion, the improved self-support function is adopted to preprocess the original data. The process of data fusion is divided into three steps: Firstly, the feature of the same kind of sensor data is extracted by the adaptive weighted average method as the input source of BPNN. Then, BPNN is trained and its output is used as the basic probability assignment (BPA) of D-S evidence theory. Finally, Bhattacharyya Distance (BD) is introduced to improve D-S evidence theory from two aspects of evidence distance and conflict factors, and multi-source data fusion is realized by D-S synthesis rules. In practical application, a three-level information fusion framework of the data level, the feature level, and the decision level is proposed, and the safety status of buildings is evaluated by using multi-source sensor data. The results show that compared with the fusion result of the traditional D-S evidence theory, the algorithm improves the accuracy of the overall safety state assessment of the building and reduces the MSE from 0.18 to 0.01%.

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