International Journal of

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Vaulted structure has been in use for nearly 4000 years and believed to have been studied by scientists and builders for nearly 2000 years. There are few publications about the geometry and constructional aspects of arches and vaults before Renaissance age. One of the most interesting works on this subject belongs to Jamshid Kashani known as a mathematician. Ghiayth Al-Din Kashani, has made some valuable contribution in the field of building construction in general and vaulted structures in particular. This paper aims to introduce and analyze a part of his work on building construction, that is on pointed arches. In this paper first we provide a short history of pointed arch. Then we will see a number of works from Roman period to Kashani age which had some contribution about arches. The third part of the paper deals with Kashani's book Meftah Al-Hesab or the key of mathematics. The final section of the paper has devoted to Kasahni's contribution to pointed arches. And finally showing one of the calculation charts which could be used to find different parts of the arches can be the best case in the point.

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Early design decisions made on building configuration and spatial design affect seismic behavior of buildings. Therefore introducing design guidelines and empirical methods implemented to assess seismic behavior of buildings have been proposed as an appropriate approach. Such concept helps architects to take into the consideration that how their preliminary design decisions influence downstream structural results. In previous efforts guidelines for seismic assessment of irregular buildings configuration and also torsional effect of interior walls-layout have been introduced. While seismic effects of the adjacency in spatial units and associated structural systems are almost ignored. This paper tries to show how spatial layout and specifically adjacency of spatial units affect the seismic behavior of a building when (1) the roofing systems are non-uniform and (2) specific spatial units correspond to the specific types of roofs with specific seismic behavior. The paper focuses on masonry buildings with curved roofing systems. To develop guidelines and empirical methods, we selected conventional masonry residential buildings implemented in central arid and semi-arid zones of Iran, traditionally, as case study. Two approaches have been proposed in the form of seismic guidelines and empirical methods. First, a method is introduced to show how adjacency of spatial units and associated vaults with different seismic vulnerability can affect the vulnerability of whole structure according to the effect of “successive damage”. An empirical method is also proposed to estimate the value and shape of distribution of lateral forces on load-bearing walls transferred by adjacent curved roofs, since lateral forces increase seismic vulnerability of load-bearing walls