0000000000177653
AUTHOR
Gaetano Zingone
Restoration of the Zisa Palace, Palermo
The building of the Zisa, commissioned by William I, began in 1164-1165; it was completed by William II in the years immediately following. It was built as a splendid place for rest and amusement, ...
Behavior of fiber reinforced concrete-filled tubular columns in compression
Experimental compression tests on steel tubular columns filled with plain concrete and fiber reinforced concrete are carried out. For each type of column three different lengths are considered in order to point out the influence of slenderness on the ductility in compression. The experimental investigations presented here have emphasized the improvement in ductility capacity obtained when fiber reinforced concrete is utilised instead of plain concrete. Moreover, the results obtained stress that the lateral displacements due to global instability are drastically reduced.
The limit state of indefinite plates on elastoplastic continuum
The limit analysis of indefinite plates resting on a continuous elastoplastic medium and subjected to a load distributed over a partial surface with a circular boundary yields the fundamental equation governing the problem. Minimum conditions are set and the solution that supplies the collapse load of the plate-soil system is found by variational calculus.
Limit analysis of frame systems stiffended by panels
Limit analysis of frame systems stiffened by nonperforated and perforated panels by discretisation of the panels into one-dimensional finite elements. The fundamental equation of the problem arrived at is very general in scope and is of particular interest for the analysis of the structural-systems subjected to shear as the effect of the wind or of the earthquake one.
Some experiences about the retrofitting of tower masonry structures
The paper deals with some intervention methodologies for tower structures belonging to the architectural Italian heritage, aimed to the reduction of the collapse risk under normal and exceptional loads. Then the special investigation for evaluation of the structural safety of the bell tower of Palermo Cathedral and the following collapse risk mitigation are described. First through the paper the history of the tower is presented then in situ and laboratory tests are described. The interventions adopted after the investigation are discussed and finally the dynamic tests for the validation of the analytical model used in the assessment of the seismic vulnerability are showed.
Strength and Ductility of Hollow Circular Steel Columns Filled with Fibre Reinforced Concrete
Publisher Summary This chapter investigates the behavior of hollow circular steel cross-sections filled with Fiber Reinforced Concrete (FRC), subjected to monotonic loads. The casting of different types of composite members—steel columns, steel columns filled with Normal Strength Concrete (NSC), and steel columns filled with Fiber Reinforced Concrete (FRC) was employed. The columns were tested in uniaxial compression utilizing a universal testing machine operating in displacement control. The maximum strength of composite members filled with FRC was 20% higher than that recorded for steel pipes filled with FRC. After the peak load was reached, failure was due to the crushing of concrete and…
Ultimate load analysis of plate foundations
The behaviour of circular plates used as isolated foundations is investigated on the basis of earlier studies[6], [7] of the limit state of indefinite plates resting on elastoplastic continua and subjected to distributed loads. The upshot is an easy-to-use procedure of ultimate load analysis that permits the determination of: --the limit load for simultaneous collapse of plate and continuum --and the limit load for collapse of the continuum only according to the different behaviour of the two elements constituting the system.
Probable collapse mechanisms in indefinite plates on an elastoplastic continuum
With reference to a theory expounded in a previous note [2] on the limit state behaviour of plates resting on an elastoplastic continuum subject to distributed loads, probable collapse mechanisms are considered in order to supplying more tractable solutions for technical practice. As the case is a general one, it is shown that the results obtained are suitable for following the load carrying capacity of plates and the relative collapse mechanism as the limit resistance of the soil and the spread of the load acting on it vary.
Limit analysis of a beam in bending immersed in an elastoplastic medium
The behavior of the beam-soil system is examined within the scope of the bilateral schematization of ideal elastoplastic bodies, in the following work stages; the expression for the limit load is supplied for each stage: Two peculiar features of the problem are highlighted:1) the “plastic hinge migration” phenomenon, due to the elastic unloading of the material, and2) the successive propagation of plastification in the soil which, being related to the displacement of the hinges in the beam, leads to the identification of the collapse mechanism of the systme.