Publication:
Shear strength and displacement capacity of squat reinforced concrete shear walls
Shear strength and displacement capacity of squat reinforced concrete shear walls
dc.contributor.advisor | Vidot Vega, Aidcer L. | |
dc.contributor.author | Adorno Bonilla, Carlos M. | |
dc.contributor.college | College of Engineering | en_US |
dc.contributor.committee | Wendichansky Bard, Daniel A. | |
dc.contributor.committee | Montejo Valencia, Luis A. | |
dc.contributor.committee | López Rodríguez, Ricardo R. | |
dc.contributor.department | Department of Civil Engineering | en_US |
dc.contributor.representative | Parés Matos, Elsie I. | |
dc.date.accessioned | 2018-09-19T19:22:19Z | |
dc.date.available | 2018-09-19T19:22:19Z | |
dc.date.issued | 2016 | |
dc.description.abstract | Squat reinforced concrete (RC) walls are essential structural components in nuclear power facilities (NPP) and in many civil structures. An adequate prediction of the shear strength and displacement capacity of these elements are important for the seismic design and performance assessment of structures whose primary lateral force resisting system is comprised by squat walls. These walls have aspect ratios less than or equal to 2. Due to their geometry, squat shear walls tend to have shear-dominated behavior while exhibiting strong coupling between flexural and shear responses. This dissertation presents an evaluation of current expressions for the prediction of peak shear strength and displacement capacity of squat RC walls available in US design codes and in the literature. An updated database was assembled with the results of moderate to large-scale experimental tests walls with shear-dominated failures and subjected to cyclic loads found in the literature. Key parameters influencing the peak shear strength and displacement capacity were identified and improved predictive equations were developed by calibration against the available data. Multiple-linear regression analyses were used to develop the predictive equations. It was found that the peak shear strength of such walls has not been adequately addressed by current US code equations in ASCE 43-05 and ACI 349-13 / ACI 318-14 since there is significant scatter on the predictions. It was also found that the peak shear strength equations in current US codes and standards tend to over-estimate the strength of squat RC walls with rectangular cross section, as well as to considerably under-estimate the peak shear strength of the squat RC walls with enlarged boundary elements considered in the assembled database. Experimental data suggested that allowable drift limits requred by ASCE 7-10 design code provisions for damage control are unconservative for the case of squat walls. Finally, two simplified analytical modeling approaches were presented. A Fiber-Based Model with flexure-shear interaction and a Macro-Hysteretic model were studied. A tri-linear backbone, calculated with the developed strength and displacement capacity expressions, was proposed to use in conjunction with the Macro-Hysteretic model for the nonlinear-cyclic analysis of squat RC walls. | en_US |
dc.description.abstract | Los muros robustos de hormigón armado son componentes estructurales esenciales en plantas de energía nuclear y en muchas otras estructuras civiles. Una predicción adecuada de su resistencia a cortante y capacidad de desplazamiento es importante para el diseño y evaluación de desempeño de estructuras cuyo sistema de resistencia a carga lateral consiste de muros robustos. Estos muros tienen una relación de aspecto igual o menor a 2. Debido a su geometría, los muros de corte robustos tienden a mostrar un comportamiento dominado por cortante y un fuerte acoplamiento entre las respuestas a flexión y a cortante. Esta disertación presenta una evaluación de algunas expresiones existentes para la predicción de la capacidad a cortante y la capacidad de desplazamiento, encontradas en los reglamentos de diseño de EEUU y en la literatura. Se ensambló una base de datos actualizada, con los resultados experimentales de muros robustos de escala moderada a grande, con falla dominada por cortante y sujetos a carga lateral cíclica, hallados en la literatura. Se identificaron los parámeteros influyentes en la resistencia a cortante y en la capacidad de desplazamiento, y se desarrollaron ecuaciones para la predicción de ambos, mediante la calibración con los datos experimentales disponibles. Se usó el análisis de regresión lineal multi-variable para el desarrollo de las ecuaciones. Se encontró que en los tres reglamentos de construcción de EEUU, ASCE 43-05, ACI 349-13 y ACI 318-14, no se estima adecuadamente la resistencia a cortante de los muros robustos de hormigón armado ya que estos producen gran dispersión en los estimados de capacidad. Además se encontró que las provisiones de los reglamentos de diseño de EEUU tienden a sobre-estimar la resistencia de muros robustos con sección rectangular y a sub-estimar considerablemente la resistencia de muros robustos con elementos de borde agrandados. El código ASCE 7-10 recomienda límites de distorción de entrepiso permisibles que resultan no-conservadores para el caso de los muros robustos de hormigón armado. Finalmente, se evaluaron dos metodologías existentes para la modelación de muros robustos: un modelo basado en fibras con interacción flexión-cortante y un modelo Macro-Histerético. Se propuso una curva tri-linear para estimar la envolvente de carga-desplazamiento, calculada con las ecuaciones desarrolladas para la predicción de resistencia máxima a cortante y la capacidad de desplazamiento. Se propuso utilizar el modelo de envolvente tri-lineal en conjunto con el modelo Macro-Histerético estudiado para el análisis cíclico no-lineal de muros robustos de hormigón armado. | en_US |
dc.description.graduationSemester | Fall | en_US |
dc.description.graduationYear | 2016 | en_US |
dc.description.sponsorship | Awards NRC-HQ-12-G-38-0018 and NRC-HQ-84-14-G-0057 from the US Nuclear Regulatory Commission. The statements, findings, conclusions, and recommendations are those of the author and do not necessarily reflect the view of the US Nuclear Regulatory Commission. Additional financial support was provided by Intelligent Diagnostics for Aging Civil Infrastructure, under the IGERT Fellowship Program of the National Science Foundation (Award Number DGE-0654176). | en_US |
dc.identifier.uri | https://hdl.handle.net/20.500.11801/924 | |
dc.language.iso | en | en_US |
dc.rights.holder | (c) 2016 Carlos M. Adorno Bonilla | en_US |
dc.rights.license | All rights reserved | en_US |
dc.subject | shear strength | en_US |
dc.subject.lcsh | Shear walls | en_US |
dc.subject.lcsh | Concrete walls | en_US |
dc.subject.lcsh | Boundary element methods | en_US |
dc.subject.lcsh | Lateral loads | en_US |
dc.subject.lcsh | Earthquake hazard analysis | en_US |
dc.title | Shear strength and displacement capacity of squat reinforced concrete shear walls | en_US |
dc.type | Dissertation | en_US |
dspace.entity.type | Publication | |
thesis.degree.discipline | Civil Engineering | en_US |
thesis.degree.level | Ph.D. | en_US |