Strength capacity of unreinforced masonry cylindrical columns under seismic transverse forces

Abstract

In this paper, the seismic resistance of unreinforced masonry (URM) cylindrical columns is investigated with an equivalent static analysis procedure. To this end, an existing numerical model developed for the stability analysis of masonry elements with rectangular cross-section is utilized and modified for the cylindrical columns. In the numerical model which takes into account the cracking of the sections and the second-order effects, the columns are divided ideally into sufficiently high number of elements, each having uniform curvature. The columns are modeled as prismatic cantilevers undergoing their own weights, eccentric vertical loads and distributed and concentrated static horizontal loads equivalent to the inertia actions. By considering two examples of columns, firstly a reference column and secondly a column from a real building, lateral seismic coefficient versus top drift level curves are obtained. On the basis of these curves, lateral load behavior of the columns is interpreted and maximum seismic load values which can be resisted by each column are determined. Implementing parametric analyses on the reference column, sensitivity of the seismic resistance to parameters such as column slenderness, magnitude and eccentricity of vertical top load, and the flexibility parameter is determined. The influence of some structural imperfections such as the deviation from vertical on the seismic resistance is also discussed in the paper.

Analytical model for the out‐of‐plane response of vertically spanning unreinforced masonry walls

“…These assumptions were used in previous studies to investigate the influence of the axial load eccentricity, the effect of initial deflections, the effect of self‐weight, the presence of uncracked bricks or blocks, and the influence of lateral loads on the buckling capacity of unreinforced masonry walls or columns. In a few studies, they were also used to investigate the lateral response of the walls . In those studies, however, numerical procedures based on the finite element method, in which the wall was discretized into small elements with constant curvature, were used to solve the equations.…”

“…They were extensively used in the past to determine the axial force that triggers instability of unreinforced masonry piers and columns. Such studies considered eccentric axial loads or combinations of constant lateral loads and increasing axial loads . In the present paper, these assumptions are used to analyse the out‐of‐plane behaviour of unreinforced masonry walls when subjected to a constant axial load and a varying lateral load.…”

“…Such studies considered eccentric axial loads 17,[21][22][23][24][25][26][27] or combinations of constant lateral loads and increasing axial loads. [18][19][20][28][29][30][31][32][33] In the present paper, these assumptions are used to analyse the out-of-plane behaviour of unreinforced masonry walls when subjected to a constant axial load and a varying lateral load. This approach is used to derive an analytical solution of the pushover curve of the wall, when this latter is subjected to loading conditions similar to those arising in seismic events.…”

Numerical Assessment of the Selected Supporting Element Carrying Capacity of Critical Infrastructure Facility / Szacowanie Numeryczne Nośności Wybranego Elementu Konstrukcyjnego Obiektu Infrastruktury Krytycznej

“…Zastosowanie metod numerycznych pozwala na określenie odpowiedzi konstrukcji poddanej obciążeniu impulsowemu, co zostało zaprezentowane w pracach [7,8,14], jak i poprzednich badaniach autorów [10,11,12]. Również analizy nośności konstrukcji, w tym elementów z imperfekcjami są często rozwiązywane metodami numerycznymi, a nawet analitycznymi [1,6,9]. Jednak przeprowadzenie pełnej analizy nośności uwzględniającej odkształcenie struktury na skutek oddziaływania MW jest bardzo czasochłonne ze względu na wykorzystanie jawnego schematu rozwiązywania (analiza dynamiczna), szczególnie dla etapów statycznego obciążenia wstępnego i końcowego [2,5,17].…”

Effect of FRP Wraps on the Compressive Behaviour of Slender Masonry Columns

“…The author analysed a cantilever column, taking into consideration no-tension material with a parabolic stress-strain law, and solved the problem by means of the finite difference method. Gurel et al (2012) [13] adapted to circular sections the numerical model developed by La Mendola and Papia (1993) [14] for investigating the stability of masonry elements with rectangular cross-sections. More recently, Fossetti et al (2015) [15] proposed a discretized beam analysis for calculating the axial load vs. lateral deflection curves for clay brick masonry columns.…”