Dynamic hydrographic variations in northwestern Arabian Gulf over the past three decades: Temporal shifts and trends derived from long-term monitoring data

Along with building slender and longer span structures, vibration serviceability becomes more important considerations in bridge design and maintenance. In this study, vibration serviceability and deflection limit for long span cable bridges are investigated using long-term monitoring data such as accelerations and displacements of bridges. Exampled bridges are Yi Sun-Sin Grand Bridge (suspension bridge, main span length=1,545m) and 2nd Jindo Grand Bridge (cable stayed bridge, main span length=344m). Long-term data are analyzed and compared with various design codes, guidelines, and other research results. Probability of exceedance are calculated for each criterion. Regarding on deflection limits, Korean Bridge Design Code (Limit State Design) specifies L/400 and L/350 for cable stayed and suspension bridges, respectively. Saadeghvaziri suggested deflection limit based on natural frequency, acceleration limit of 0.5 m/s² and vehicle speed. Various human comfort criteria on vibration are also applied including ISO standards. The results of this study are expected to be useful reference for the design, the proper planning and deflection review of the long span cable bridges around the world. Further researches are required to find the optimum deflection or vibration criteria for long span bridge and their effects on bridge clearance and elevation.

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Proposed evaluation methods for vibration serviceability of long span cable bridges

IABSE Congress, Christchurch 2021: Resilient technologies for sustainable infrastructure ◽

10.2749/christchurch.2021.0327 ◽

2021 ◽

Author(s):

E.-S. Hwang ◽

M. T. Hwang ◽

D. Y. Kim ◽

K. J. Park

Keyword(s):

Heavy Traffic ◽

Damping Ratio ◽

Flexible Structures ◽

Evaluation Methods ◽

Monitoring Data ◽

Long Span ◽

Vibration Serviceability ◽

Long Term Monitoring ◽

Term Monitoring

Vibration serviceability becomes more important considerations in design and maintenance, especially for slender and flexible structures such as long span cable bridges. In this study, various evaluation methods for vibration serviceability for long span cable bridges are proposed. These methods are based on short and long-term monitoring data such as accelerations and displacements of bridges. Proposed methods include (1) method of evaluating vibration amplitude based on Reiher-Meister curves, (2) method of evaluating variations in natural frequencies and damping ratio,(3) method of weighted rms(root-mean-square) acceleration based on ISO 2631-1, and (4) probabilistic analysis using long-term monitoring data. These methods are applied to example cable bridge and cases of normal traffic, heavy traffic, windy condition and sudden abnormal vibration are considered. The results of this study are expected to be implemented to real bridge monitoring system for real-time and periodic evaluation of vibration serviceability.

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Forecasting structural strains from long-term monitoring data of a traditional Tibetan building

Structural Control and Health Monitoring ◽

10.1002/stc.2300 ◽

2018 ◽

Vol 26 (1) ◽

pp. e2300 ◽

Cited By ~ 2

Author(s):

Na Yang ◽

Xiaobin Bai

Keyword(s):

Monitoring Data ◽

Long Term Monitoring ◽

Term Monitoring

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FORECAST OF THE REFORMATION OF THE KRASNOYARSK RESERVOIR COASTAL ZONE IN THE KURTAK VILLAGE

Bulletin of Udmurt University. Series Biology. Earth Sciences ◽

10.35634/2412-9518-2019-29-2-267-278 ◽

2019 ◽

Vol 29 (2) ◽

pp. 267-278

Author(s):

G.Yu. Yamskikh ◽

A.V. Kozhukhovsky ◽

K.V. Marusin ◽

E.A. Fedorova

Keyword(s):

Economic Activity ◽

Similar Type ◽

Coastal Processes ◽

The Past ◽

The Reformation ◽

Long Term Monitoring ◽

Verification Of Models ◽

The Village ◽

Term Monitoring

The article presents the analysis and prediction of coastal processes at the site of the Krasnoyarsk reservoir in the village of Kurtak where there are the most intensive processes of coastal reshaping. Over the past 50 years, the coast has receded here by an average of 350 m and continues to actively collapse at a speed of 3-5 m per year. Despite the fact that the intensity of coastal processes in this area has significantly decreased (mainly due to the general decrease in the level of the Krasnoyarsk reservoir), the rate of retreat of the shore is still high. However, it can be concluded that for the researched area the coastal reshaping does not pose a real threat to economic activity in the next 30 years. The article tested various methods of forecasting coastal processes, selected the most appropriate for the shores of a similar type. Verification of models was carried out on the basis of data of long-term monitoring of the site under consideration, which gave the chance to compare results of forecasts on different techniques to real retreat of the coast on this site.

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