Search results for " Experimental Investigation"
showing 10 items of 10 documents
Experimental investigation on high-strength fibre-reinforced concrete beams subjected to bending and shear
2008
The results of an experimental campaign carried out on a number of high-strength concrete beams loaded in 4-point bending are presented in this paper, where the roles of the both steel hooked fibres and the transverse reinforcement are investigated, for different values of the shear span. All tests were displacement-controlled. The results – mostly in terms of load-deflection curves – confirm what is well known in the literature, that an adequate amount of steel fibres can turn a brittle shear-type failure into a ductile flexural-type failure, to the advantage of the ultimate bearing capacity in flexure and shear, that can be fully exploited without increasing the transverse reinforcement. …
Experimental Investigation on the Compressive Behaviour of Clay Brick Masonry Columns Confined by BFRP or Steel Wires
2016
This paper presents the results of an experimental research aiming to investigate on the compressive behavior of full size clay brick masonry columns reinforced with Basalt Fiber Reinforced Cementitious Matrix (BFRCM) or with steel wires collaring. Uniaxial compressive tests were performed on eight retrofitted columns and four control specimens. Two masonry strength were considered by varying the mortar grade. Results are presented and discussed in terms of axial stress-strain relationships, failure modes and crack patterns of the specimens tested up to failure. For the limit of investigated variables, comparisons with unreinforced specimens show the ability of these alternative techniques …
Reward networks changes in the brain of pathological gamblers: a resting state functional magnetic resonance imaging study
2017
Aims and objectives Methods and materials Results Conclusion Personal information References
Flow characteristics in a vegetated flume
2008
Vegetation altering hydrodynamic conditions of an open channel flow controls the exchanges of sediment, nutrients and contaminants. Thus, the knowledge of the hydraulic characteristics of flow over vegetation is very important to support the management of fluvial processes. In this paper the flow over real flexible vegetation is experimentally studied. A 2D-ADV (Acoustic Doppler Velocimeter) is used to measure the local flow velocities for different vegetation concentrations and varying the discharge and the flume slope. The flow velocity measures are used to test the hyperbolic tangent profile of a pure mixing layer and to evaluate the mixing-layer parameters. The formation of turbulence s…
Stress transfer and failure mechanisms in steel-concrete trussed beams: Experimental investigation on slab-thick and full-thick beams
2018
Abstract This study presents the results of an experimental investigation on semi-precast Hybrid Steel Trussed-Concrete Beams (HSTCBs) for analyzing the failure modes and the stress transfer mechanism between concrete and embedded steel elements (plate and truss). The available literature presents previous studies carried out by the authors mainly focused on the understanding of the local transfer mechanism by means of push-out tests. Conversely, in this paper original the results of laboratory tests conducted on six specimens of full-size HSTCBs subjected to four-point bending, with variation in the shear span, are reported on. From these results, the authors are able to assess the failure…
Debonding Phenomena in CFRP Strengthened Calcarenite Masonry Walls and Vaults
2009
In this paper the results of an experimental investigation on full-scale reinforced masonry elements like vaults and walls are presented. The masonry type is constituted by calcarenite ashlars and bed joint mortar and the reinforcement is constituted by Carbon Fibre Reinforced Polymer (CFRP) strips. Preliminary experimental results obtained in a previous research by the authors on the local behaviour at the interface CFRP-calcarenite are summarized. Tests with controlled displacement are carried out on out-of-plane loaded walls and cylindrical vaults loaded at a quarter of the span. Results of tests carried out before and after the application of the reinforcement made it possible to evalu…
Performance Assessment of Basalt FRCM for the Confinement of Clay Brick Masonry Cylinders
2021
Fibre Reinforced Cementitious Matrix (FRCM) composites have been proved to be a suitable strengthening material for masonry structures in the last years. Moreover, basalt fibres are increasingly used as reinforcement of composites as a more sustainable alternative to glass fibres. The goal of this work is to investigate the effectiveness of basalt FRCM to confine masonry circular columns. A total of eighteen clay brick masonry cylinders were tested in compression. The specimens were cored from two different masonry assemblies and wrapped with one or two layers of BFRCM composite. The stress-strain curves and the gains of strength and strain capacity of confined cylinders compared to the con…
Nonlinear FE analysis of out-of-plane behaviour of masonry walls with and without CFRP reinforcement
2014
Abstract The out-of-plane behaviour of unreinforced and CFRP reinforced masonry wall is studied by means of experimental investigation and numerical FE modelling. The latter is based on a linear constitutive law both for ashlars and mortar joints constituting masonry and the lines of potential delamination are taken into account by means of an interface element with bi-linear law, reproducing the opening failure mode. When reinforcement is introduced, an interface element with bi-linear law is also used, reproducing sliding failure mode. Comparison between numerical and experimental results show the reliability of the modelling. Moreover, a parametric analysis is carried out in order to inv…
Strengthening of Masonry Columns with BFRCM or with Steel Wires: An Experimental Study
2016
Nowadays, innovative materials are more frequently adopted for strengthening historical constructions and masonry structures. The target of these techniques is to improve the structural efficiency with retrofitting methods while having a reduced aesthetical impact. In particular, the use of basalt fiber together with a cementitious matrix emerges as a new technique. This kind of fiber is obtained by basalt rock without other components, and consequently it could be considered a natural material, compatible with masonry. Another innovative technique for strengthening masonry columns consists of applying steel wires in the correspondence of mortar joints. Both techniques have been recently pr…
Microstructure and mechanical behaviour of a saturated compacted scaly clay
2011
The paper presents the results of a research on the influence of structure characteristics on the mechanical behaviour of a saturated compacted scaly clay. To this aim, mechanical properties of compacted scaly clay samples after saturation are compared with the corresponding properties measured on the clay reconstituted in the laboratory. For the stress range explored in the experimental programme, compacted scaly clay samples are stiffer and stronger than reconstituted clay samples owing to their greater density. Collected results are discussed taking in consideration microstructure characteristics of the compacted and reconstituted clay samples