Acoustic emission (AE) monitoring studies have been carried out under controlled laboratory conditions on plain concrete beams and reinforced concrete (RC) beams. The results of AE statistics have revealed interesting features of the various stages of stress induced micro- fracturing and growth leading to the failure of plain concrete beams and RC beams. The experimental
This paper presents the recent results of experimental investigations under dynamic loading aimed at disclosing the loading rate effect (mainly related to seismic loading range) on crack propagation in quasi-brittle fracture. Twenty four wedge-splitting tests were conducted using a servo-hydraulic machine under loading rates ranged from 10-3 mm/s to 101 mm/s. Strain gauges were mounted
Most infrastructures are reinforced concrete (RC) structures. In order to deal with the security and durability of RC structures, the stackholders have to survey the noticeable signs of degradation resulting from interactions between the environment and the constitutive materials. As the matter of fact, these interactions can reveal cracks, which are major with respect to
The contribution presents novel observations on unreinforced masonry made of solid clay brick units and surrounding mortar joints. Focus is the brittle-ductile interaction of the two constituents in form of the so-called masonry prism test under axial compression. The experimental observations include Digital Image Correlation (DIC) data from a newly acquired 3-D DIC system to
Drying of cement-based materials induces drying shrinkage, which may cause prestress loss or/and cracking if strains are (self or externally) restrained. Drying shrinkage is difficult to predict, since it depends on the material mix, mechanical and hygral boundary conditions, geometry … This paper focuses on the study of size effect on final drying shrinkage, which
X-ray Computed Tomography (XCT) is a powerful technology that can accurately image the internal structures of composite and heterogeneous materials in three-dimensions (3D). In this study, in-situ micro XCT tests of concrete specimens under progressive compressive loading are carried out. The aim of the observations is to gain a better understanding of 3D fracture and
Relatively little research has been undertaken on the time-dependent in-service behaviour of composite concrete slabs with profiled steel decking as permanent formwork and little guidance is available to practicing engineers for predicting long-term deflection. The drying shrinkage profile through the thickness of a slab is known to be greatly affected by the impermeable steel deck
The upcoming need of concrete structures designed against impulsive and extreme load due to natural hazards, industrial accidents or terrorists attack requires analytical modeling capable of reproducing material behavior in this range of loading. When a concrete structure is submitted to an impact or an explosion loading, material may be submitted to high triaxial compression
Three-point bending tests were performed on cement mortar beams of rectangular cross section. The specimens were subjected to abrupt compressive step loading while simultaneous Acoustic and Electrical Signal Emissions were recorded. In order to evaluate the development of the fracture process, characteristics of acoustic emissions and electrical current signals were studied and compared by isolating
Thepaperpresentsapreliminarylocalinvestigationrelatedtoslidingonamortarjointdue to excessive shear force, mechanism observed during testing of masonry arches and barrel vaults re- inforced with Externally Bonded Fibre Reinforced Polymers (EB FRP) at their extrados. This activity was aimed at evaluating a possible contribution of the FRP reinforcement to joint resistance. Four- teen V-shape Peel Tests (VPT) have been performed, which consist