scholarly journals Mathematical Modeling of Linear Static and Dynamic Analysis for Pier Height Effect on the Structural Performance of Bridges Structures

2021 ◽  
Vol 8 (4) ◽  
pp. 617-625
Author(s):  
Ali Fadhil Naser ◽  
Hussam Ali Mohammed ◽  
Ayad Ali Mohammed
Keyword(s):  
Time History ◽  
Bending Moment ◽  
High Strength ◽  
Response Spectra ◽  
Structural Performance ◽  
Static And Dynamic Analysis ◽  
Compressive Stresses ◽  
History Analysis ◽  
Negative Bending ◽  
Dynamic Frequency

The results of linear static analysis explained that the increasing of pier heights was leaded to rise the values of positive bending moment, tensile stresses, and downward vertical deflection. Whereas the compressive stresses and negative bending moment were decreased, indicating that the structural performance of bridge structure representing by stiffness, bearing capacity of structural members, and elasticity will decrease and the bridges structures will be damaged. Therefore, the bridges structures need safe design when using tall piers by adopting high quality materials such as high strength concrete, more steel reinforcement, more prestressed tendons, and increasing of cross section dimensions of girders and piers. The results of modal analysis show that the un-loaded dynamic frequency for three types of bridges models were decreased when the pier heights were increased, indicating that the stiffness of bridges structure was became low with higher pier height. According to response spectra and time history analysis results, the loaded dynamic frequency (vibration state) and dynamic displacement were increased when the pier heights were increased, showing that the bridge of structure will suffer from high vibration when the pier height was high. It can be concluded that from this study, the piers heights have significant effects on the static and dynamic structural performance of bridges structures under traffic loads.

Seismic performance of Greater Jakarta LRT with added lead rubber bearing using non-linear time history analysis

2021 ◽  
Author(s):  
Iswandi Imran ◽  
Marie Hamidah ◽  
Tri Suryadi ◽  
Hasan Al-Harris ◽  
Syamsul Hidayat
Keyword(s):  
Linear Time ◽  
Time History ◽  
Time History Analysis ◽  
Performance Level ◽  
Structural Performance ◽  
Isolation System ◽  
Rubber Bearing ◽  
Lead Rubber Bearing ◽  
History Analysis ◽  
Seismic System

<p>In order to overcome stringent seismic requirement in the new Greater Jakarta Light Rail Transit Project, a breakthrough seismic system shall be chosen to obtain expected structural performance. This seismic system shall be designed to provide operational performance level after strong earthquake events. To achieve the criteria, seismic isolation system using Lead Rubber Bearings is chosen. With this isolation system, Greater Jakarta LRT has become the first seismically isolated infrastructure and apparently an infrastructure with the largest numbers of LRBs in one single project in Indonesia. More than 10.400 Pcs LRBs are used for the first phase of the construction and the numbers will be certainly increased in the next phase of the construction. To evaluate the structural performance, non-linear time history analysis is used. A total of 3 pair matched ground motions will be used as the input for the response history analysis. The ability of the lead rubber bearing to isolate and dissipate earthquake actions will determine its structural performance level. This will be represented by the nonlinear hysteretic curves obtained throughout the earthquake actions.</p>

scholarly journals Dynamic Response Evaluation of Long-Span Reinforced Arch Bridges Subjected to Near- and Far-Field Ground Motions

2018 ◽  
Vol 8 (8) ◽  
pp. 1243 ◽  
Author(s):  
Iman Mohseni ◽  
Hamidreza Lashkariani ◽  
Junsuk Kang ◽  
Thomas Kang
Keyword(s):  
Ground Motion ◽  
Dynamic Performance ◽  
Time History ◽  
Bending Moment ◽  
Element Model ◽  
Structural Performance ◽  
Far Field ◽  
Inelastic Behavior ◽  
Earthquake Loads ◽  
Arch Bridges

This study assessed the structural performance of reinforced concrete (RC) arch bridges under strong ground motion. A detailed three-dimensional finite element model of a 400 m RC arch bridge with composite superstructure and double RC piers was developed and its behavior when subjected to strong earthquakes examined. Two sets of ground motion records were applied to simulate pulse-type near- and far-field motions. The inelastic behavior of the concrete elements was then evaluated via a seismic time history analysis. The concept of Demand to Capacity Ratios (DCR) was utilized to produce an initial estimate of the dynamic performance of the structure, emphasizing the importance of capacity distribution of force and bending moment within the RC arch and the springings and piers of the bridge. The results showed that the earthquake loads, broadly categorized as near- and far-field earthquake loads, changed a number of the bridge’s characteristics and hence its structural performance.

scholarly journals Comparison of Scaling Ground Motions Using Arithmetic with Logarithm Values for Spectral Matching Procedure

2020 ◽  
Vol 2020 ◽  
pp. 1-14
Author(s):  
Rui Zhang ◽  
Dong-sheng Wang ◽  
Xiao-yu Chen ◽  
Hong-nan Li
Keyword(s):  
Ground Motions ◽  
Time History ◽  
Response Spectra ◽  
Time History Analysis ◽  
Spectral Matching ◽  
Moment Resisting Frame ◽  
History Analysis ◽  
Moment Resisting ◽  
Structural Responses ◽  
Structural Time

In recent studies, spectral matching is the most commonly proposed method for selecting earthquake records for time-history analysis of structures. However, until now, there have been no serious investigations of the effects of coordinate values on the scaling of ground motions. This paper investigated the influence of using arithmetic and logarithmic values of response spectra in spectral matching procedures (i.e., ASM and LSM methods) on the results of nonlinear structural time-history analysis. Steel moment resisting frame structures of the 3-, 9-, and 20-stories, which represent low-, medium-, and high-rise buildings, respectively, were used as examples. Structural benchmark responses were determined by calculating the arithmetic mean and median of peak interstory drift ratio (PIDR) demands based on the three record sets developed by the American SAC Steel Project. The three record sets represent seismic hazard levels with 50%, 10%, and 2% probabilities exceeded in 50 years, and their average acceleration spectra were also taken as the target spectrum. Moreover, another 40 record components for selection were scaled both by ASM and LSM methods. The seven components whose spectra were best compatible with the target spectra were selected for the structural time-history analysis. The scale factors obtained by the LSM method are nearly larger than that of the ASM method, and their ranking and selection of records are different. The estimation accuracies of structural mean (median) responses by both methods can be controlled within an engineering acceptable range (±20%), but the LSM method may cause larger structural responses than the ASM method. The LSM method has a better capacity for reducing the variability of structural responses than the ASM method, and this advantage is more significant for longer-period structures (e.g., 20-story structure) with more severe nonlinear responses.

Time History Analysis of Steel Tall Buildings

2014 ◽  
Vol 1025-1026 ◽  
pp. 918-921 ◽  
Author(s):  
Yong Chul Kim ◽  
Sung Won Yoon
Keyword(s):  
Wind Direction ◽  
Time History ◽  
Tall Buildings ◽  
Bending Moment ◽  
Ground Level ◽  
Structural Systems ◽  
Loading Conditions ◽  
Normal Stresses ◽  
History Analysis ◽  
Principal Axes

The results of wind tunnel experiments were used to conduct time history analyses of three conventional square cross-section tall buildings with different structural systems. The primary purpose of the study was the direct comparison of the effects of the wind loads on the steel tall buildings. Time history analyses were conducted by applying local wind forces to the center of each floor. The results showed that, although the bending moments in the ground-level column on the two principal axes were different, the peak normal stresses were almost the same regardless of the structural systems. Similar observations were made regarding the tip displacements. Furthermore, analyses for the various loading conditions revealed that the contribution of the bending moment in the across-wind direction was the largest, followed by that in the along-wind direction. The ratio of the peak normal stresses for different loading conditions were observed to be almost the same regardless of the structural systems.

scholarly journals Analisis Kinerja Bangunan Rangka Baja dengan Bresing Tahan Tekuk terhadap Beban Gempa

2021 ◽  
Vol 6 (2) ◽  
pp. 98
Author(s):  
Ilham Ilham
Keyword(s):  
Pushover Analysis ◽  
Time History ◽  
Steel Structures ◽  
Time History Analysis ◽  
Nonlinear Time History Analysis ◽  
Structural Performance ◽  
History Analysis ◽  
Immediate Occupancy ◽  
Nonlinear Time History ◽  
Modal Pushover

ABSTRAKPenggunaan bresing tahan tekuk dapat menjadi solusi atas kebutuhan struktur tahan gempa di Indonesia. Disipasi energi pada elemen bresing tahan tekuk dilakukan melalui kinerja plastifikasi bagian inti bresing akibat beban tarik dan tekan. Penelitian ini berisi kajian kinerja dari bangunan rangka baja beraturan dengan bresing tahan tekuk (BRB) dengan variasi level ketinggian lantai yaitu 3 lantai, 8 lantai dan 15 lantai. Analisis struktur 3D dilakukan dengan dua prosedur analisis yaitu modal pushover dan nonlinear time history pada program ETABS. Hasil analisis menunjukkan bahwa pemilihan elemen BRB sangat mempengaruhi kinerja struktur, yang terlihat dari pola drift yang terjadi. Untuk struktur beraturan dengan berbagai ketinggian, tingkat kinerja struktur dengan BRB cukup baik, yaitu Immediate Occupancy (IO) akibat beban gempa rencana. Plastifikasi hanya terjadi pada BRB, dan kelelehan pada balok mulai terbentuk sampai mekanisme keruntuhan terjadi. Hasil modal pushover dengan nonlinear time history pada bangunan 15 lantai yang cukup mirip menunjukkan bahwa modal pushover dapat digunakan untuk memprediksi kinerja struktur BRB yang beraturan.Kata kunci: kinerja struktur, bresing tahan tekuk, immediate occupancy, modal pushover, nonlinear time history ABSTRACTBuckling restrained braces (BRB) can be an alternative solution for earthquake resistant steel structure in Indonesia. The energy dissipation for buckling restrained elements is conducted through yielding of the core due to tension or compression forces. This study presents an evaluation of the structural performance of steel structures with BRB varying in heights, 3-story, 8-story and 15-story. The 3D structural analysis was carried out with ETABS software using 2 methods, Modal Pushover and Nonlinear Time History. The results shows that the selection of BRB elements greatly affected the structural performance, showed by the drift pattern. For regular structures with variation in heights, structures with BRB behaved satisfactory under the design load with the performance level of Immediate Occupancy (IO). Yielding was limited to BRB members, and afterwards the yielding occurred on beams until collapse. The results of modal pushover and time history analysis for 15-story structure are similar, thus modal pushover can be used to predict the performance of regular structural system with BRB.Keywords: structural performance, buckling restrained brace, immediate occupancy, modal pushover analysis, nonlinear time history analysis

Effect of sliding pendulum isolator bearing to the structural performance of Becakayu Ahmad-Yani continuous span bridge

2021 ◽  
Author(s):  
Tri Suryadi ◽  
Tony Sihite ◽  
Wanda Heryudiasari
Keyword(s):  
Seismic Isolation ◽  
Passive Control ◽  
Linear Time ◽  
Time History ◽  
Structural Performance ◽  
Easy Access ◽  
Isolation System ◽  
Toll Road ◽  
History Analysis ◽  
Road Project

<p>Structural assessment is an important procedure to be done for checking and reviewing the realization of the expected structural performance level. In a normal circumstance, it is common that the bridge is designed with life-safety performance that implies undamaged superstructures and foundations, and damaged substructures. This design philosophy is normally known as “ductile substructure and elastic superstructure” concept. The location of the damages shall be predefined to allow easy access for future repairs after earthquake events. Nowadays, a different design approach is introduced through the use of passive control devices. One of the most common technology for bridges is the seismic isolation system using sliding pendulum isolator bearing as the seismic controlling device. Ahmad Yani Continuous Span Bridge in Becakayu Toll Road Project is designed with pendulum isolator bearings. Through non-linear time history analysis, the structural performance of Ahmad Yani Bridge will be evaluated. It is expected that all the dissipation mechanism occurs in the pendulum bearings, with both superstructure and substructures are still in elastic and essentially elastic conditions.</p>

Evaluation of N-M Model on Simulating Seismic Response of High-Rise SRC Structure

2013 ◽  
Vol 477-478 ◽  
pp. 1060-1063
Author(s):  
Guo Bin Bu ◽  
Jian Cai ◽  
Kang Ning Li
Keyword(s):  
Interaction Model ◽  
Time History ◽  
Bending Moment ◽  
Dynamic Responses ◽  
Biaxial Bending ◽  
Fiber Model ◽  
High Rise ◽  
History Analysis ◽  
Moment Interaction ◽  
Dynamic Time

The axial load-biaxial bending moment interaction model (N-M model) is developed based on the metal plasticity theory, and its reliability in structural analysis is evaluated. Employing CANNY program, linear and nonlinear dynamic time history analysis is conducted to a 32-story SRC structure. The dynamic responses are compared between N-M model and fiber model cases. The results show that N-M model can simulate well the dynamic response of the high-rise hybrid structures. Besides, N-M model has clear mechanical concept and is much simpler compared to fiber model, and the computational efficiency can be greatly improved by using N-M model.

The Whittier Narrows, California Earthquake of October 1, 1987—Response of a Tall Masonry Building

1988 ◽  
Vol 4 (2) ◽  
pp. 319-337
Author(s):  
G. C. Hart ◽  
R. D. Ewing
Keyword(s):  
Structural Damage ◽  
Structural Engineering ◽  
Time History ◽  
Shear Walls ◽  
Response Spectra ◽  
Masonry Building ◽  
Ground Acceleration ◽  
Spectra Analysis ◽  
Lumped Parameter ◽  
History Analysis

The Hilton Hotel in Whittier, California is an eight story reinforced hollow unit concrete masonry building. It experienced a peak ground acceleration of approximately sixty percent gravity without visible structural damage. This paper performs an analysis of the building from two perspectives. The first is a structural engineering design perspective using the structural mechanics assumptions consistent with the new strength design criteria for hollow unit shear walls in the 1988 UBC and a response spectra analysis. The second perspective is based on a nonlinear lumped parameter time history model and a step-by-step time history analysis.

Analysis on Seismic Pounding of Curved Bridge

2011 ◽  
Vol 90-93 ◽  
pp. 800-804
Author(s):  
Qiang Xu ◽  
Xing Jun Qi
Keyword(s):  
Three Dimensional ◽  
Time History ◽  
Bending Moment ◽  
Relative Displacement ◽  
Internal Force ◽  
Curved Bridge ◽  
Reference Base ◽  
History Analysis ◽  
Seismic Pounding ◽  
The Impact

Based on the impact phenomenon between the end of the beam and the bridge abutment of the curved continuous bridge during earthquakes, a spatial finite element calculating model with collision element is presented. The law of collision is studied by the nonlinear contact time history analysis method under two three-dimensional ground motions. The variation laws of relative displacement and the internal force at the bottoms of piers are researched. In addition the changing of displacement and internal force at the end diaphragm are studied. The results show that the pounding action can easily lead to significant collision forces between the end beam and the abutment of the curved bridge which increases the axial force of girder evidently. The collision forces and longitudinal displacements from the inner to outer of the diaphragm generally are showed by an increasing trend, and the pounding action is more fierce under Elcentro ground motion than that under Tianjin ground motion.There is no relative displacement of consolided pier, bending moment and shear force of the consolided pier are greater than that of the mobile pier.The conclusions from the present study may serve as a reference base for seismic design of continuous curved bridges.

scholarly journals Parametric Study of P-Delta Effect on Irregular RC Structure with Structural Systems Having Different Density of Shear Walls

2021 ◽  
pp. 492-503
Author(s):  
Yash Patel ◽  
Mr Jigar Zala ◽  
Prof. Deepak R. Tarachandani
Keyword(s):  
Parametric Study ◽  
Dynamic Instability ◽  
Response Spectrum ◽  
Drift Time ◽  
Time History ◽  
Bending Moment ◽  
Shear Walls ◽  
Structural Systems ◽  
Base Shear ◽  
History Analysis

P-Delta analysis affect the seismic responses of structures. When the structure responds elastically, its importance can be insignificant, but it is relevant when the structure responds to an inelastic set. The P-∆ effect normally raises the structural displacement response. Dynamic instability can also occur when the system is exposed to extreme earthquake motions. Plan irregularities can lead to substantial eccentricity between the centre of mass and the centre of rigidity in the RC framed structure, which can lead to a negative lateral and torsional response. Irregular structures require more careful structural evaluation to reach a suitable behaviour during an earthquake. In this research, a parametric study will be conducted on G+29 RC framed buildings having plan irregularity with consideration of the P-delta effect. Time history analysis, response spectrum analysis and static co-efficient method will be conducted to evaluate results of different structural systems and study the parameters like Displacement, Storey drift, Time period, Axial force, Base Shear, Bending Moment, etc with the help of structural analysis software ETABs.

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