Response analysis of yielding structures coupled to rocking walls with supplemental damping

2021 ◽  
Author(s):  
Mehrdad Aghagholizadeh ◽  
Nicos Makris
Keyword(s):  
Response Analysis ◽  
Supplemental Damping ◽  
Rocking Walls

Direct Displacement-Based Seismic Design of Propped Rocking Walls

2015 ◽  
Vol 31 (1) ◽  
pp. 179-196 ◽  
Author(s):  
Afsoon Nicknam ◽  
Andre Filiatrault
Keyword(s):  
Nonlinear Response ◽  
Design Procedure ◽  
Seismic Intensity ◽  
Ground Shaking ◽  
Direct Displacement Based Design ◽  
Seismic Force ◽  
Supplemental Damping ◽  
Displacement Based ◽  
Rocking Walls ◽  
Strong Ground

A direct displacement-based design (DDBD) methodology is described for propped rocking walls (PRWs). PRWs represent a novel seismic force-resisting system that combines passive supplemental damping devices with unbonded post-tensioned concrete rocking walls. The key aspect of the proposed design procedure is the closed-form derivation of the stabilized hysteretic response of PRWs under reverse cyclic loading. This allows the direct application of the DDBD procedure to satisfy desired displacement performance objectives under prescribed levels of seismic intensity. Nonlinear response analyses are conducted on a prototype PRW structure, designed according to the proposed DDBD procedure to evaluate its performance under strong ground shaking.

scholarly journals Unbonded Post-tensioned Precast Concrete Walls With Rocking Connections: Modeling Approaches and Impact Damping

2021 ◽  
Vol 7 ◽  
Author(s):  
Dimitrios Kalliontzis ◽  
Maryam Nazari
Keyword(s):  
Structural Damage ◽  
Precast Concrete ◽  
Seismic Energy ◽  
Shake Table Tests ◽  
Modeling Approaches ◽  
Supplemental Damping ◽  
Rocking Walls ◽  
Rocking Wall ◽  
Wall System ◽  
Impact Damping

Over the past two decades, precast concrete members have been utilized in seismically resilient structures. In developing these structures, different techniques have been used for connecting the precast members to the foundation. In building construction, unbonded post-tensioning (PT) tendons can anchor a precast wall to the foundation, resulting in the so-called rocking wall system. The rocking wall system develops a dry connection with the foundation and provides moment resistance by means of the PT tendons. The PT tendons remain elastic when the wall is subjected to design-level ground motions to preserve the re-centering capability of the wall. Moreover, the structural damage is concentrated near the wall toes and can be minimized with proper detailing of the toes. Rocking wall systems can consist of a Single precast Rocking Wall (SRW), which uses no supplemental damping, or walls with supplemental damping in the form of viscous or hysteretic energy dissipating devices. In addition to the supplemental damping, rocking walls dissipate the seismic energy through their impacts on the foundation base, their inherent viscous damping, and the hysteresis of concrete near the wall base. While the investigation of rocking walls continues to gain interest, there is no widely accepted means of modeling their dynamic behavior. This paper investigates two popular approaches for modeling rocking walls with and without supplemental damping: the finite element method and analytical modeling. The ability of the two approaches to capture the local and global responses of the walls is evaluated against shake table tests of walls with multiple-level intensity base motions. Next, the behavior characteristics of the two modeling approaches and their ability to simulate impact damping are discussed.

A Dose-Response Analysis of Nicotine Sensitization in Adolescent Rats D2-Primed as Neonates

2010 ◽  
Author(s):  
Elizabeth A. Hanchak ◽  
Meredith L. Smith ◽  
Jessie J. Smith ◽  
Marla K. Perna ◽  
Russell W. Brown
Keyword(s):  
Dose Response ◽  
Response Analysis ◽  
Adolescent Rats

ENCORE: A weight-based exacerbation dose response analysis of mepolizumab in severe asthma with eosinophilic phenotype

Pneumologie ◽  
2017 ◽  
Vol 71 (S 01) ◽  
pp. S1-S125
Author(s):  
I Pouliquen ◽  
D Austin ◽  
N Gunsoy ◽  
SW Yancey
Keyword(s):  
Severe Asthma ◽  
Dose Response ◽  
Response Analysis

The Effects of Vitamin K1 and Warfarin on Prothrombin Expression in Human Hepatoblastoma (HepG2) Cells

1992 ◽  
Vol 68 (01) ◽  
pp. 040-047 ◽  
Author(s):  
C Scott Jamison ◽  
Bryan F Burkey ◽  
Sandra J Friezner Degen
Keyword(s):  
Total Protein ◽  
Hepg2 Cells ◽  
Enzyme Linked Immunosorbent Assay ◽  
Response Analysis ◽  
Secreted Protein ◽  
Mrna Levels ◽  
Vitamin K1 ◽  
Maximal Increase ◽  
Protein Levels ◽  
Warfarin Treatment

SummaryCultures of human hepatoblastoma (HepG2) cells were treated with vitamin K1 or warfarin and prothrombin antigen and mRNA levels were determined. With 3 and 6 h of 10 µg vitamin K1 treatment secreted prothrombin antigen levels, relative to total secreted protein levels, were increased 1.5-fold and 2.1-fold, respectively, over ethanol-treated control levels as determined by an enzyme-linked immunosorbent assay. Dose-response analysis with 3 h of 25 µg/ml vitamin K1 treatment demonstrated a maximal increase of 2.0-fold in secreted prothrombin antigen levels, relative to total secreted protein levels, over ethanol-treated control levels. Pulse-chase analysis with 35S-methionine and immunoprecipitation of 35S-labelled prothrombin demonstrated that, with vitamin K1 treatment (25 µg/ml, 3 h), the rate of prothrombin secretion increased approximately 2-fold and the total amount (intra- and extracellular) of prothrombin synthesized increased approximately 50% over ethanol-treated control levels. Warfarin treatment (1, 5, or 10 µg/ml, 24 h) resulted in decreases in secreted prothrombin antigen levels, relative to total protein levels to approximately 85%, 87% or 81% of ethanol-treated control levels. Analysis of total RNA isolated from these cultures by Northern and solution hybridization techniques demonstrated that prothrombin mRNA was approximately 2.1 kb and that neither vitamin K1 nor warfarin treatment affected the quantity of prothrombin mRNA (ranging from 240–350 prothrombin mRNA molecules per cell). These results demonstrate that vitamin K1 and warfarin, in addition to effects on γ-carboxylation, affect prothrombin synthesis post-transcriptionally, perhaps influencing translation, post-translational processing and/or secretion mechanisms.

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