Probabilistic Seismic Performance of Rocking-Foundation and Hinging-Column Bridges

2012 ◽  
Vol 28 (4) ◽  
pp. 1423-1446 ◽  
Author(s):  
Lijun Deng ◽  
Bruce L. Kutter ◽  
Sashi K. Kunnath

Many engineers are hesitant to specify rocking foundations for ordinary bridges because of the unsubstantiated notion that rocking bridges are more susceptible to instability than conventional fixed-base bridges. A parametric study using a finite element model including large deformation effects compares the performance and stability of stiff, flexible, tall, and short hinging-column and rocking-foundation systems. Eighty different ground motions, scaled using incremental dynamic analysis, were considered. Results show that, in a probabilistic sense, bridges with rocking foundations are more stable than bridges with hinging columns if their fundamental periods are the same and if base shear coefficients to initiate hinging or rocking mechanisms are the same. Maximum drifts are not much affected by changing between rocking and hinging mechanisms except near collapse, but residual drifts are smaller for rocking systems. The results also challenge the notion that rocking systems require a different design approach than hinging column systems.

Materials ◽  
2021 ◽  
Vol 14 (12) ◽  
pp. 3346
Author(s):  
Bora Gencturk ◽  
Hadi Aryan ◽  
Mohammad Hanifehzadeh ◽  
Clotilde Chambreuil ◽  
Jianqiang Wei

In this study, an investigation of the shear behavior of full-scale reinforced concrete (RC) beams affected from alkali–silica reactivity damage is presented. A detailed finite element model (FEM) was developed and validated with data obtained from the experiments using several metrics, including a force–deformation curve, rebar strains, and crack maps and width. The validated FEM was used in a parametric study to investigate the potential impact of alkali–silica reactivity (ASR) degradation on the shear capacity of the beam. Degradations of concrete mechanical properties were correlated with ASR expansion using material test data and implemented in the FEM for different expansions. The finite element (FE) analysis provided a better understanding of the failure mechanism of ASR-affected RC beam and degradation in the capacity as a function of the ASR expansion. The parametric study using the FEM showed 6%, 19%, and 25% reduction in the shear capacity of the beam, respectively, affected from 0.2%, 0.4%, and 0.6% of ASR-induced expansion.


2020 ◽  
pp. 136943322096527
Author(s):  
Longji Dang ◽  
Rui Pang ◽  
Rui Liu ◽  
Hongmei Ni ◽  
Shuting Liang

This paper aims to investigate the seismic performance of hollow floor interior slab-column connection (HFISC). In this new connection system, several tube fillers are placed in slab to form hollow concrete. Moreover, locally solid zone, shear components, and hidden beam around the connections are installed to improve the bearing capacity and ductility of specimens. Three slab-column connections with different shear components were tested under cyclic loading and every specimen was constructed with parallel tube fillers in the north direction and orthogonal tube fillers in the south direction. The seismic behavior of specimens was evaluated according to the hysteretic response, skeleton curve, ductility, stiffness degradation, and energy dissipation. A finite element model was then developed and validated by a comparison with the experimental results. Based on experimental results and finite element analysis results, the relative effects of the hollow ratio of slab, the ratio of longitudinal reinforcement, the shear area of bent-up steel bars, and the arm length of welding section steel cross bridging were elucidated through parametric studies. This new slab-column connection showed better plastic deformation capacity while the bearing capacity was kept. Specimens with parallel tube fillers showed better seismic behavior than those of specimens with orthogonal tube fillers.


2020 ◽  
Vol 10 (16) ◽  
pp. 5489
Author(s):  
Rulin Zhang ◽  
Shili Chu ◽  
Kailai Sun ◽  
Zhongtao Zhang ◽  
Huaifeng Wang

This paper investigates the effect of the multi-directional components of ground motion on an unanchored steel storage tank. Both the liquid sloshing effect and contact behavior between the foundation and tank are included in the study. A three-dimensional model for a foundation–structure–liquid system is numerically simulated using the finite element method. The Lagrange fluid finite element method (FEM) in ANSYS is used to consider the liquid–solid interaction. In the liquid–structure–foundation interaction model, the contact and target elements are adapted to simulate the nonlinear uplift and slip effects between the tank and the foundation. Three earthquake ground motions are selected for evaluating the seismic behavior of the tank. Comparisons are made on the horizontal displacement, “elephant-foot” deformation, stress, base shear and moment, sloshing of the liquid, uplift, as well as slip behavior under the application of the unidirectional, bi-directional and tri-directional components. Under the selected ground motions, the horizontal bi-directional seismic component has great influence on the liquid sloshing in the tank studied in this paper. The vertical seismic component produces high compressive axial stress, and it also makes the uplift and slide of the tank bottom increase significantly. The applicability of this conclusion should be carefully considered when applied to other types of ground motion inputs.


2002 ◽  
Vol 29 (4) ◽  
pp. 622-626
Author(s):  
Peter Lee ◽  
Ying H Chui ◽  
Ian Smith ◽  
Noel Mailvaganam ◽  
Gerry Pernica

This paper presents finite element simulations of curling of unreinforced concrete topping laid over wood floor systems. The finite analysis consists of two parts. The first part calculates the relative moisture distribution with respect to the age of the concrete, while the second determines the topping curling deformation based on modulus of elasticity, density, and shrinkage of the concrete. With the finite element model the curling profile at any point in time can be predicted. Predictions agree reasonably well with measurements from a full-sized wood floor with a thin concrete topping. A model-based parametric study was performed. For the floor size investigated the results of the parametric study indicate that curling is greatly influenced by topping thickness and relative humidity of the surrounding air. Although the modelling as discussed is a preliminary approach, it provides a basis for further enhancements that will address factors such as creep and relaxation of concrete and deformation of the underlying floor system. Key words: finite element analysis, concrete topping, wood floor, curling, shrinkage.


1989 ◽  
Vol 16 (3) ◽  
pp. 227-238 ◽  
Author(s):  
Bruno Massicotte ◽  
Denis Beaulieu ◽  
André Picard

This paper deals with the stabilizing effect of girts and cladding on columns in light industrial buildings. The construction aspects of such systems are briefly reviewed and a description of their behavior is presented. Solutions available to determine column strength in column–girt–diaphragm systems are reviewed. The use of a finite-element-based software is proposed as the only practical way to analyze this type of structural system. Results of a large parametric study using a finite element model are presented and a method to evaluate the ultimate strength of actual columns is introduced. Finally, a simple hand design method is derived. Key words: diaphragm, design, finite element, girt, column, stability, statistics.


2018 ◽  
Vol 24 (7) ◽  
pp. 95
Author(s):  
Salah R. Al-Zaidee ◽  
Ehab Ghazi Al-Hasany

This study aims to show, the strength of steel beam-concrete slab system without using shear connectors (known as a non-composite action), where the effect of the friction force between the concrete slab and the steel beam has been investigated, by using finite element simulation. The proposed finite element model has been verified based on comparison with an experimental work. Then, the model was adopted to study the system strength with a different steel beam and concrete slab profile. ABAQUS has been adopted in the preparation of all numerical models for this study. After validation of the numerical models, a parametric study was conducted, with linear and non-linear Regression analysis. An equation regarding the concrete slab-steel beam system strength in non-composite action has been pointed out. Where the actual strength of the beam without using shear connectors has been located in between the full composite action and non-composite action. However, partial-composite action has been noted, due to the effectiveness of friction force which makes the beam behave as composite before the slip occurs.  


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