SEISMIC PERFORMANCE OF SCALED IBS BLOCK COLUMN FOR STATIC NONLINEAR MONOTONIC PUSHOVER EXPERIMENTAL ANALYSIS

2017 ◽  
Vol 80 (1) ◽  
Author(s):  
Chun-Chieh Yip ◽  
Abdul Kadir Marsono ◽  
Jing-Ying Wong ◽  
Shu-Chi Lee
Keyword(s):  
Seismic Performance ◽  
Shear Capacity ◽  
Full Scale ◽  
Load Prediction ◽  
Base Shear ◽  
Scaling Factors ◽  
Scaled Model ◽  
Performance Levels ◽  
Non Linear ◽  
Block Column

This paper presents the seismic performance of the down scaled 1:5 model IBS block column with non-linear static analysis. The aim of this research is to access the ultimate capacity and structural behaviour of the IBS block column. This paper demonstrates the theoretical prediction of the full-scale prototype strength based on scaling factors at non-linear state. Besides, this research investigates the ultimate shear capacity, stiffness, bolt strength, inter-storey drift and block separation for prediction of seismic performance levels. Concrete material properties, mix specification and steel reinforcement detailing for scaled model are tabulated in this paper. The methodology of this research begins with full scale prototype design, scaling to the small model and followed by the scaled model fabrication. Theoretical lateral load prediction associated with scaling factors are also performed. The experiment test was carried out on the assembled scaled 1:5 IBS block column with proper displacement measuring equipment on test rig and graphical capture tools. The data of roof top displacement with base shear capacity, inter-storey drift and gap separations were tabulated for discussions. The tested ultimate roof top displacement was 128 mm with 3.1 kN base shear. The calculated elastic stiffness of the IBS block column was 0.137 kN/mm, followed by yielding stiffness of 0.033 kN/mm and 0.014 kN/mm plastic stiffness. The significant inter-storey drift was due to cracking and crushing of column blocks edges. The measured maximum separation gap was 24.4 mm located at 340 mm height due to the rocking of the column. Based on seismic performance levels indicator from FEMA 273 & 356, the column was in the state of immediate occupancy with 21 mm roof top displacement and 1.7 kN base shear. The life safety is limited at 65.27 mm roof top displacement with 2.4 kN of base shear. All scaled down data was then reverted to full scale prototype capacity according with the respective scaling factors. It concluded that the IBS blockwork column is capable of resisting the seismic event without falling of the blocks that endanger the occupant life at the maximum credible earthquakes of 1.3 g horizontal spectral acceleration equivalent to X+ Mercalli’s scale.

Seismic Reliability of a Fixed Offshore Platform Against Collapse

2014 ◽  
Author(s):  
Mojtaba Dyanati ◽  
Qindan Huang
Keyword(s):  
Seismic Performance ◽  
Limit State ◽  
Shear Capacity ◽  
Offshore Platform ◽  
Ultimate Limit State ◽  
State Function ◽  
Base Shear ◽  
Offshore Structure ◽  
Seismic Reliability ◽  
Fixed Offshore Platform

As many jacket type steel platforms have been constructed in the highly active seismic area, seismic reliability evaluation of such structures is desirable. Ultimate limit state (ULS) with base shear capacity and demand can be used to estimate seismic performance of fixed offshore platform against collapse. Base shear capacity is evaluated from pushover analysis on a 3D finite element model of the offshore structure using different load patterns. Base shear demand is calculated from spectral acceleration at a given site and the total mass of the platform. Uncertainties are considered in both capacity and demand evaluations. With the limit state function, seismic fragility of a prototype structure is assessed using reliability analysis. The results indicate that various load patterns affect the seismic performance evaluation. It is also found that the steel yield stress is a critical parameter in the reliability of the steel jacket platforms.

scholarly journals Experimental Investigation into the Seismic Performance of Prefabricated Reinforced Masonry Shear Walls with Vertical Joint Connections

2021 ◽  
Vol 11 (10) ◽  
pp. 4421
Author(s):  
Zhiming Zhang ◽  
Fenglai Wang
Keyword(s):  
Seismic Performance ◽  
Cross Sections ◽  
Shear Walls ◽  
Construction Method ◽  
Shear Capacity ◽  
Initial Stiffness ◽  
Equivalent Viscous Damping ◽  
Displacement Ductility ◽  
Reinforced Masonry ◽  
Cracking Performance

In this study, four single-story reinforced masonry shear walls (RMSWs) (two prefabricated and two cast-in-place) under reversed cyclic loading were tested to evaluate their seismic performance. The aim of the study was to evaluate the shear behavior of RMSWs with flanges at the wall ends as well as the effect of construction method. The test results showed that all specimens had a similar failure mode with diagonal cracking. However, the crack distribution was strongly influenced by the construction method. The lateral capacity of the prefabricated walls was 12% and 27% higher than that of the corresponding cast-in-place walls with respect to the rectangular and T-shaped cross sections. The prefabricated walls showed better post-cracking performance than did the cast-in-place wall. The secant stiffness of all the walls decreased rapidly to approximately 63% of the initial stiffness when the first major diagonal crack was observed. The idealized equivalent elastic-plastic system showed that the prefabricated walls had a greater displacement ductility of 3.2–4.8 than that of the cast-in-place walls with a displacement ductility value of 2.3–2.7. This proved that the vertical joints in prefabricated RMSWs enhanced the seismic performance of walls in shear capacity and ductility. In addition, the equivalent viscous damping of the specimens ranged from 0.13 to 0.26 for prefabricated and cast-in-place walls, respectively.

Seismic Performance of RC Short Columns Strengthened with BFRP

2013 ◽  
Vol 351-352 ◽  
pp. 1532-1536 ◽  
Author(s):  
Bin Ding ◽  
Li Jun Ouyang ◽  
Zhou Dao Lu ◽  
Wei Zhen Chen
Keyword(s):  
Seismic Performance ◽  
Failure Modes ◽  
Low Cost ◽  
Economic Cost ◽  
Shear Capacity ◽  
Good Prospect ◽  
Loading Test ◽  
Fiber Reinforced Plastic ◽  
Short Columns ◽  
Reinforced Plastic

BFRP has excellent strength, durability, thermal properties and economic cost. To test seismic performance of short columns strengthened with BFRP. Low cyclic loading test was conducted on one comparative short column and two RC short columns strengthened with BFRP. The test shows that short columns warped by BFRP show excellent failure modes, shear capacity, ductility and energy dissipation. As a new fiber reinforced plastic, BFRP has a good prospect in the area of seismic strengthening for its low cost and comprehensive mechanical properties.

Guidelines for CFD Simulations of Spar VIM

2013 ◽  
Author(s):  
Charles Lefevre ◽  
Yiannis Constantinides ◽  
Jang Whan Kim ◽  
Mike Henneke ◽  
Robert Gordon ◽  
...  
Keyword(s):  
Reynolds Number ◽  
Test Data ◽  
Model Test ◽  
Model Tests ◽  
Full Scale ◽  
Mooring System ◽  
Time Step ◽  
Cfd Simulations ◽  
Scaled Model ◽  
Sway Motion

Vortex-Induced Motion (VIM), which occurs as a consequence of exposure to strong current such as Loop Current eddies in the Gulf of Mexico, is one of the critical factors in the design of the mooring and riser systems for deepwater offshore structures such as Spars and multi-column Deep Draft Floaters (DDFs). The VIM response can have a significant impact on the fatigue life of mooring and riser components. In particular, Steel Catenary Risers (SCRs) suspended from the floater can be sensitive to VIM-induced fatigue at their mudline touchdown points. Industry currently relies on scaled model testing to determine VIM for design. However, scaled model tests are limited in their ability to represent VIM for the full scale structure since they are generally not able to represent the full scale Reynolds number and also cannot fully represent waves effects, nonlinear mooring system behavior or sheared and unsteady currents. The use of Computational Fluid Dynamics (CFD) to simulate VIM can more realistically represent the full scale Reynolds number, waves effects, mooring system, and ocean currents than scaled physical model tests. This paper describes a set of VIM CFD simulations for a Spar hard tank with appurtenances and their comparison against a high quality scaled model test. The test data showed considerable sensitivity to heading angle relative to the incident flow as well as to reduced velocity. The simulated VIM-induced sway motion was compared against the model test data for different reduced velocities (Vm) and Spar headings. Agreement between CFD and model test VIM-induced sway motion was within 9% over the full range of Vm and headings. Use of the Improved Delayed Detached Eddy Simulation (IDDES, Shur et al 2008) turbulence model gives the best agreement with the model test measurements. Guidelines are provided for meshing and time step/solver setting selection.

Impact of Damping Scaling Factors on Direct Displacement-Based Design

2016 ◽  
Vol 32 (2) ◽  
pp. 843-859 ◽  
Author(s):  
Cuiyan Kong ◽  
Mervyn J. Kowalsky
Keyword(s):  
Response Spectra ◽  
Equivalent Linearization ◽  
Base Shear ◽  
Limit States ◽  
Scaling Factors ◽  
Equivalent Viscous Damping ◽  
Direct Displacement Based Design ◽  
Displacement Response Spectra ◽  
Performance Limit States ◽  
Displacement Based

Damping scaling factors (DSFs) play an important role in direct displacement-based design (DDBD) as they provide a means to establish displacement response spectra for damping values beyond 5%. Response spectra for multiple damping values are needed for DDBD as the approach relies on equivalent linearization, expressed in the form of effective stiffness and equivalent viscous damping, to establish design forces for prescribed performance limit states. In the past, DSFs based on the Eurocode have been employed for DDBD; however, recent research has resulted in more robust DSF models. This paper examines the accuracy of the current DSF equation used in DDBD across the parameters that are important for structural design. A nonlinear regression analysis is performed based on the data obtained by the Rezaeian et al. (2014) model, and a base shear adjustment factor (SAF) is proposed for application to the DDBD base shear equation.

scholarly journals Studi Perbandingan Analisis Struktur Rumah 2 Lantai Menggunakan Kayu Glulam dan Kayu Solid Terhadap Beban Gempa. (Hal. 85-94)

2019 ◽  
Vol 5 (1) ◽  
pp. 85
Author(s):  
Ramdhan Taufik ◽  
Erma Desmaliana ◽  
Amatulhay Pribadi
Keyword(s):  
Construction Material ◽  
Pushover Analysis ◽  
Solid Wood ◽  
Wood Products ◽  
Basic Material ◽  
Class Iii ◽  
Base Shear ◽  
Non Linear ◽  
The Difference ◽  
Immediate Occupancy

ABSTRAKKondisi geografis Indonesia memiliki struktur tektonik kompleks. Kondisi ini membuat perencanaan rumah tinggal 2 (dua) lantai membutuhkan pertimbangan khusus dari segi kekuatan dan kekakuan. Penggunaan material kayu sebagai bahan konstruksi di Indonesia masih jarang digunakan. Kayu glulam adalah suatu produk kayu rekayasa yang dibuat dari beberapa bilah kayu yang direkatkan dengan arah sejajar serat menggunakan perekat berupa lem. Penelitian ini bertujuan untuk mengidentifikasi respon struktur pada rumah tinggal menggunakan material kayu glulam dan solid dengan bantuan program ETABS 2016. Berdasarkan analisis yang telah dilakukan, diperoleh nilai periode struktur, gaya geser dasar, dan simpangan antar lantai antara seluruh model menunjukan hasil yang berbeda, perbedaan diakibatkan dari hasil konversi berat jenis dan modulus of elastisity berdasarkan BS EN 1194:1999. Berdasarkan analisis non-linier pushover didapatkan bahwa kayu glulam Nyatoh (kayu kelas III) berada pada level pada kinerja B to IO (Immediate Occupancy), dimana hasil tersebut tidak berbeda jauh dengan kayu solid Bangkirai (kayu kelas I).Kata Kunci: rumah tinggal, kayu glulam, non-linier pushover ABSTRACTGeographical condition of Indonesia has a complex tectonic structure. These conditions create  2-storyhome-planning that require special consideration in terms of strength and rigidity. The use of wood as a construction material in Indonesia is still rarely used. Glulam wood is a wood products engineering made from wooden slats several glued with the direction of the parallel fibers using adhesives. This research aims to identify the structure of the response at home using basic material glulam and solid wood with the help of ETABS 2016 programs. Based on the analysis that has been done, obtained the value of the structure periode, base shear force, and interstory drift between all models show different results, the difference is due to the results of specific gravity conversion and modulus of elasticity base on BS EN 1194:1999. Based on non-linear pushover analysis, it shows that Nyatoh glulam wood (class III wood) was at the level of the B to IO (Immediate Occupancy) performance, where the results were not much different from Bangkirai solid wood (class I wood).Keywords: home livingstructure, glulam wood, non-linear pushover

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