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Compressive strength of solid clay brick masonry: calibration of experimental tests and theoretical issues
No full textLoad carrying capacity of masonry arches with stochastic compressive strength
No full textThe standard assessment procedures for masonry arches assume the compressive strength
of masonry as a deterministic variable while it is well known that masonry mechanical
parameters suffer from large scattering. In this paper, the load carrying capacity of masonry
arches is addressed by means of Kinematic Limit Analysis (Mechanism Method) assuming
the material compressive strength as a random variable. The failure probability of all the
admissible mechanisms is estimated and the global collapse probability is conservatively
provided by the Cornell approximation. The application of the procedure to a single span arch
bridge shows that for arch-type structures it can provide a filter to the compressive strength
randomness by reducing the data scattering. Discussion is provided on the safety factors
defined by masonry codes and their effect on the safety assessment of masonry arches
Risposta meccanica della muratura di mattoni pieni presso-inflessa rinforzata con fibre di carbonio
No full textThe solid clay brickwork of a 150 years-old bridge is studied through a compressive test on cylinders (= 150 mm) proposed by UIC (Union Internationale des Chemins de Fer) and flat jacks. FEM analyses, showing the stress distribution inside the specimen, explain the activation, inside the cylinder, of a sand-glass shaped core bearing the applied load, which makes the collapse mechanism of the UIC test partially different from the observed mechanisms for solid clay brickwork. The test results are compared to classical approaches and to other experimental data showing that the proposed test underestimates the compressive strength of masonry. Besides, the evaluation of the elastic average properties is found to be still an open issu
Stochastic distribution of compressive strength: effects on the load carrying capacity of masonry arches
No full textThe standard assessment procedures for masonry arches assume the compressive
strength of masonry as a deterministic variable. In this paper, the load carrying capacity of
masonry arches is addressed by means of Kinematic Limit Analysis (Mechanism Method)
assuming the material compressive strength as a random variable. Based on the failure
probability of each admissible mechanism, the global collapse probability is provided by the
Cornell approximation. The application of the procedure to a single span bridge shows that, for
arch-type structures, the C.o.V. of the load carrying capacity is less than the C.o.V. of the
compressive strength. Discussion is provided on the safety factors defined by masonry codes
and their effect on the safety assessment of masonry arche
Mechanical response of solid clay brick masonry reinforced with CFRP strips under eccentrical loading'
No full textCompressive strength of solid clay brick mansory under eccentric loading
No full textArches, vaults and pillars generally experience eccentric normal force. As a consequence, the classical theories of masonry collapse, developed for concentrically compressed brickwork, are not directly applicable. In this paper experimental data on solid clay brick and lime-mortar masonry prisms, eccentrically loaded, are presented. Comparing the results to the response of a FEM model, some hints on the collapse mechanism of masonry show that the edge effects greatly affect the load carrying capacity of the brickwork. Besides, the plane section assumption is found to be acceptable up to the ultimate compressive strength, allowing relatively simple models to be used for arch-type structures
Compressive strength of solid clay brickwork: calibration of experimental tests
No full textThe assessment procedures for masonry structures require some mechanical parameter to be defined for masonry, at least the compressive strength. Several theoretical approaches, based on the characteristics of the constituents, i.e. bricks and mortar, have been developed but their application to existing masonry turns out to be rather difficult. Therefore, experimental approaches give a fundamental contribution to the identification of the mechanical parameters provided that proper calibration allows a reliable estimation of the experimental error. In this paper, the calibration of compressive tests on large diameter cylinders, drilled from brickwork and loaded on the lateral surfaces, is discussed on the bases of both experimental and theoretical issues. This technique is shown to reproduce the brickwork collapse mechanism, giving reliable estimates of the masonry compressive strengt
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
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