Thesis Title: Numerical study of the impact of a “green roof” on the seismic response of multistory reinforced concrete buildings

Thursday 11 October 2018, at:9:30, Venue: Hall Κ3. Α17

Examination Committee

• Associate Professor Yiannis Tsompanakis (advisor)
• Professor Konstantinos Providakis
• Dr. Prodromos Psarropoulos

Abstract:

In contrast to typical concrete slab tops, "green" roofs on top of buildings can act as filters and “green lungs” in densely populated urban environments. For this reason, they are constantly gaining ground in many countries. Taking into account that the center in many cities is full of buildings, usually such “green” roofs are mainly constructed on existing and more rarely on newly built buildings. In any case, for the construction of a "green" roof, a detailed assessment of the bearing structure is needed, emphasizing on the seismic response of the building due to the additional inertial forces caused by the addition of the "green" mass at its top.

This diploma thesis examines the seismic response of medium-rise reinforced concrete buildings before and after the addition of a "green" roof. For this purpose, various parameters influencing the construction were studied, utilizing a finite element analysis software. More specifically, two (four- and eight-storey) buildings with reinforced concrete load-bearing frame structures were examined, considering that they were constructed in two different soil types (soft and stiff). A series of dynamic nonlinear analyses was performed using a sufficient number of accelerograms recorded in suitable soil conditions.

In the first part of this thesis, a detailed description of "green" roofs, as well as a brief description of seismic hazard and seismic design norms and dynamic soil-structure interaction is presented. Subsequently, the simulation of the buildings and the performed parametric investigation are given. The results and the related discussion aim to evaluate the effect of the "green" roof on the dynamic response of the examined structures, in order to draw some initial conclusions and to provide suggestions for further investigation of the subject.