<?xml version="1.0" encoding="ISO-8859-1"?><article xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
<front>
<journal-meta>
<journal-id>0185-092X</journal-id>
<journal-title><![CDATA[Ingeniería sísmica]]></journal-title>
<abbrev-journal-title><![CDATA[Ing. sísm]]></abbrev-journal-title>
<issn>0185-092X</issn>
<publisher>
<publisher-name><![CDATA[Sociedad Mexicana de Ingeniería Sísmica A.C.]]></publisher-name>
</publisher>
</journal-meta>
<article-meta>
<article-id>S0185-092X2015000200041</article-id>
<title-group>
<article-title xml:lang="es"><![CDATA[Modelación no lineal de muros de mampostería empleando elementos de contacto]]></article-title>
<article-title xml:lang="en"><![CDATA[Nonlinear modelling of masonry walls using contact elements]]></article-title>
</title-group>
<contrib-group>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Lizárraga]]></surname>
<given-names><![CDATA[José F.]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Pérez Gavilán]]></surname>
<given-names><![CDATA[Juan José]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
</contrib-group>
<aff id="Af1">
<institution><![CDATA[,UNAM Instituto de Ingeniería ]]></institution>
<addr-line><![CDATA[ ]]></addr-line>
<country>Mexico</country>
</aff>
<aff id="Af2">
<institution><![CDATA[,UNAM Instituto de Ingeniería ]]></institution>
<addr-line><![CDATA[ ]]></addr-line>
<country>Mexico</country>
</aff>
<pub-date pub-type="pub">
<day>00</day>
<month>12</month>
<year>2015</year>
</pub-date>
<pub-date pub-type="epub">
<day>00</day>
<month>12</month>
<year>2015</year>
</pub-date>
<numero>93</numero>
<fpage>41</fpage>
<lpage>59</lpage>
<copyright-statement/>
<copyright-year/>
<self-uri xlink:href="http://www.scielo.org.mx/scielo.php?script=sci_arttext&amp;pid=S0185-092X2015000200041&amp;lng=en&amp;nrm=iso"></self-uri><self-uri xlink:href="http://www.scielo.org.mx/scielo.php?script=sci_abstract&amp;pid=S0185-092X2015000200041&amp;lng=en&amp;nrm=iso"></self-uri><self-uri xlink:href="http://www.scielo.org.mx/scielo.php?script=sci_pdf&amp;pid=S0185-092X2015000200041&amp;lng=en&amp;nrm=iso"></self-uri><abstract abstract-type="short" xml:lang="es"><p><![CDATA[RESUMEN: Se presenta la modelación de muros de mampostería simple y confinada sometidos a carga axial y lateral con el método de los elementos finitos para obtener la envolvente de resistencia a corte. Se utilizan elementos de contacto en las juntas para tomar en cuenta el comportamiento no lineal en la mampostería. Se tomaron en cuenta los dos tipos de falla más comunes: la falla en tensión (Modo I) y la falla a cortante (Modo II); en ambos casos se consideró el ablandamiento. En el rango elástico, se corroboró la consistencia de los resultados obtenidos con el modelo de elementos de contacto con los producidos con un modelo detallado y un modelo homogeneizado. En el rango no lineal, se utilizó un modelo trilineal de la superficie de fluencia que no incluye una reducción de la resistencia por el esfuerzo normal, a diferencia del esquema propuesto por otros autores que si la toman en cuenta. El efecto de esta consideración se estudió mediante la comparación de los resultados obtenidos con el modelo propuesto y los resultados numéricos y experimentales reportados en la literatura. Se comentan las principales diferencias. Finalmente, se modela un muro confinado ensayado en el laboratorio para comparar la envolvente de resistencia a corte experimental con la obtenida numéricamente. Los resultados obtenidos son bastante similares.]]></p></abstract>
<abstract abstract-type="short" xml:lang="en"><p><![CDATA[ABSTRACT: Finite element modeling of unreinforced and confined masonry walls under axial and lateral loads is presented to estimate the shear strength envelope. Nonlinear contact elements are used at the joints to take into account the masonry's nonlinear behaviour. Two of the most common types of failure were considered at the joints: failure in tension (Mode I) and shear failure (Mode II); in each case softening were taken into account. Consistency of results obtained using contact elements and those obtained using detailed modeling and homogenized model was verified in the elastic range. In the non linear range, the yield surface was charcterized with a trilinear model that does not include a shear strength reduction due to normal stress, unlike other authors. The effect of this consideration was studied by comparing the results obtained with numerical and experimental results reported in the literature. The main differences are discussed. Finally, a confined masonry wall tested in the laboratory was modelled to compare the experimental strength envelope with the one obtained numerically. The results obtained are quite similar.]]></p></abstract>
<kwd-group>
<kwd lng="es"><![CDATA[mampostería]]></kwd>
<kwd lng="es"><![CDATA[modelación]]></kwd>
<kwd lng="es"><![CDATA[energía de fractura]]></kwd>
<kwd lng="es"><![CDATA[resistencia lateral]]></kwd>
<kwd lng="es"><![CDATA[curva envolvente]]></kwd>
<kwd lng="en"><![CDATA[masonry]]></kwd>
<kwd lng="en"><![CDATA[modeling]]></kwd>
<kwd lng="en"><![CDATA[fracture energy]]></kwd>
<kwd lng="en"><![CDATA[lateral strength]]></kwd>
<kwd lng="en"><![CDATA[envelope curve]]></kwd>
</kwd-group>
</article-meta>
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