Effect of earthquake-induced transverse poundings on a 32 m span railway bridge isolated by friction pendulum bearings

The use of friction pendulum devices has recently attracted the attention of both academic and professional engineers for the protection of structures in seismic areas. Although the effectiveness of these has been shown by the experimental testing carried out worldwide, many aspects still need to be investigated for further improvement and optimisation. A thermo-mechanical model of a double friction pendulum device (based on the most recent modelling techniques adopted in multibody dynamics) is presented in this paper. The proposed model is based on the observation that sliding may not take place as ideally as is indicated in the literature. On the contrary, the fulfilment of geometrical compatibility between the constitutive bodies (during an earthquake) suggests a very peculiar dynamic behaviour composed of a continuous alternation of sticking and slipping phases. The thermo-mechanical model of a double friction pendulum device (based on the most recent modelling techniques adopted in multibody dynamics) is presented. The process of fine-tuning of the selected modelling strategy (available to date) is also described.

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Lamellar Tearing Observations Regarding the Application of European Standards in the Field of Welded Steel Constructions

Revista de Chimie ◽

10.37358/rc.18.6.6323 ◽

2018 ◽

Vol 69 (6) ◽

pp. 1352-1354

Author(s):

Anamaria Feier ◽

Oana Roxana Chivu

Keyword(s):

Bearing Capacity ◽

Brittle Failure ◽

Engineering Practice ◽

Steel Bridge ◽

Railway Bridge ◽

Welded Steel ◽

Direct Replacement ◽

Lamellar Tearing ◽

European Standards ◽

Comprehensive Study

The problem of corrosion for old steel bridges in operation is often solved by direct replacement of elements or structure. Only a few studies have been done to determine the efforts influenced by corrosion in those elements. In general, it is considered that a corroded element has exceeded the bearing capacity and should be replaced, but if the corroded element is secondary it could be treated and kept. A factor in the rehabilitation of an old steel bridge in operation is the aspect of structure. If the structure is corroded, rehabilitation decision is taken is easier. Lamellar tearing describes the cracking that occurs beneath the weld and can be characterized as a brittle failure of steel, in the direction perpendicular to the plane of rolling. The paper presents a comprehensive study on lamellar tearing and summarizes some conclusions about the prevention of them. The conclusions will be exemplified in the case of a railway bridge, with a main truss girder. The paper presents also some observations regarding the stress analysis in fillet welds, resulting from the engineering practice.

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Urban Railway Bridge Fast Evaluation Based on Cloud Computing

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.71-78.4501 ◽

2011 ◽

Vol 71-78 ◽

pp. 4501-4505

Author(s):

Ming Chen ◽

Wan Zhou

Keyword(s):

Neural Networks ◽

Cloud Computing ◽

Model Updating ◽

Condition Assessment ◽

Fe Model ◽

Railway Bridge ◽

Fast Evaluation ◽

Railway Bridges ◽

Computing Model ◽

Bridge Condition Assessment

Although modern bridge are carefully designed and well constructed, damage may occur in them due to unexpected causes. Currently, many different techniques have been proposed and investigated in bridge condition assessment. However, evaluation efficiency of condition assessment has not been paid much attention by the researchers. A fast evaluation of the urban railway bridge condition based on the cloud computing is presented. In this paper dynamic FE model and Artificial neural networks technique is applied to model updating. The cloud computing model provides the basis for fast analyses. It was found that when applied to the actually railway bridges, the proposed method provided results similar to those obtained by experts, but can improve efficiency of bridge

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