Nicola Buratti

EARTHQUAKE ACCELEROGRAM SELECTION AND SCALING PROCEDURES FOR ESTIMATING THE DISTRIBUTION OF DRIFT RESPONSE

The problem of selecting a suite of earthquake accelerograms for time-domain analyses is of particular practical and academic interest. Research in this field has led to numerous approaches for compiling suites of accelerograms that may be used to robustly estimate the median structural response. However, many applications in earthquake engineering require the estimation of the full distribution of a structural response parameter for a particular predefined scenario. This article presents an efficient procedure whereby the distributions of interstory or roof drifts may be well approximated. The procedure makes use of three-point approximations to continuous distributions and the strong correlation that exists between the spectral acceleration at the initial fundamental period of the structure and the drift response. The distributions obtained under the proposed approach are compared with a reference distribution assumed to represent the true underlying distribution of drift response. The reference distrib...

Long-Term Behaviour of Fiber-Reinforced Self-Compacting Concrete Beams

This paper describes the results of an experimental campaign aimed at investigating the long-term behaviour of beams cast using fiber-reinforced self-compacting concretes containing either steel or synthetic fibers in comparison with that of plain self-compacting concrete beams with standard reinforcement. The flexural behaviour of six different beams was investigated in a long-term four point bending test under constant loading. All the beams were pre-cracked before the long-term test. The tests showed that fibers have an important role in controlling the increase of crack opening over time. The greatest reduction in the delayed crack opening was obtained using a mixture of steel and macro synthetic fibers.

Creep Testing Methodologies and Results Interpretation

This paper presents a literature review on the main testing methodologies used to investigate the long-term behaviour of cracked FRC elements. Various tests methods such as pull-out tests, uniaxial tension tests, beam bending tests, and plate bending tests are illustrated and discussed. The paper originates from a round table held during the FRC-CREEP 2016 workshop.