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In the present article, the structural behaviour of a masonry arch bridge in Turkey is investigated. An analytical study has been conducted to provide the geometry of the structure, using laser scanning. A point cloud describing the geometry is obtained and properly transformed into a format, which is appropriate for structural analysis software (CAE). Then, a number of non-linear finite element models is developed, to simulate its structural response. Goal of the article is to highlight the influence of both continuum and discrete approaches and related constitutive laws, on the response of the bridge. Thus, continuum damage laws and a discrete model consisting of unilateral contact-friction interfaces, have been developed. Different load cases are tested and comparison between the results obtained from the different approaches is considered. The failure mechanisms and the ultimate strengths are derived and core points of the used models are highlighted.From the output of this work, it is shown how the different failure models predict the behaviour of the masonry arches. It is also shown that the three-hinge mechanism, which has been depicted in classical studies for single-span arch masonry bridges under a horizontal settlement of supports, may also be obtained for multi-arch bridges. Similarly, downward, vertical settlement of supports may result in the development of two hinges, as in single-span arches. The beneficial influence of the backfill in limiting the failure in the arch, is finally addressed in the article.

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In the present article the failure behaviour of a steel, beam type element supported against fire by protection boards, is studied. Threedimensional, coupled temperature-displacement, non-linear finite element analysis models have been developed to simulate the unprotected and protected structure. A simple modelling approach is proposed for the investigation of the influence of the gradual failure of fire protection at elevated temperatures, on the structural performance of the system, under thermal and mechanical loads. Yielding of steel is depicted and forcedisplacement diagrams are used to evaluate the ultimate behaviour of the unprotected and protected models. It is shown that for the protected structure, yielding is less severe and the time period up to maximum strength is significantly longer. Eventually, is depicted how failure of the fire protection leads to a gradual reduction of the response, in fire conditions.

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