Designing 2 Storey Building for Sustainability Designing For Life

Introduction

Two-storey buildings have become an essential part of today’s architects due to the growing population and limited space available. As innovative building designs are the prerequisites of any building architect, it is vitally important to design sustainable two-storey buildings for life. This dissertation offers a critical review of the two-storey buildings which are innovative, sustainable and sustain earthquake shocks.

Natural calamities are also a matter of great concern for building designs and materials used in building two-storey buildings. Every time a seismic event occurs somewhere around the globe, Nature reminds us that there are still many things to be done by practicing engineers to reach the goal of saving lives and property during these extreme events. The after quake statistics tell us about large economic loses and unacceptable number of lives lost. Many reasons can be found or argued about the causes that lead to the collapse of some structures in these seismic events, ranging them from plain negligence up to limitations on the knowledge the way structures behave during strong seismic events. Therefore, there is a constant challenge to every engineer for a better understanding of the patterns of behavior of building structures, knowledge that hopefully can be applied in the design and construction of the reliable structures that people needs. The intention of this dissertation is to focus on the design and materials needed to sustainable for life two-storey buildings. Dissertation Format

When a seismic action induces a horizontal rotation about a vertical axis in a building floor/roof, that behavior is called torsional response. The effect of this phenomenon is to induce additional demands of strength and ductility on some components of a building that in a hypothetical ideal building would not exist. The concern arises when these demands were not anticipated by the engineer, and no measures were taken to accommodate them. Even if the engineer clearly foresee that this high strength or ductility demands would be induced, he has to deal with the current code recommendations to handle this issue, and arguably they are insufficient in some design situations. An example of these national recommendations can be found in the "Minimum Design Loads for Buildings and Other Structures" code, in the USA, and the Building Code for the Federal District, in Mexico City. Experiences from past seismic events around the globe, have taught us that a significant number of collapsed structures had serious problems in handling the torsion induced demands. Escobar and Ayala (1998) report that a significant proportion of the observed damage in building structures during the 1985 Mexican earthquake can be attributed to ill torsional behavior. They explain that the eccentricity between the building's strength center and its mass center was relatively large in some of these collapsed buildings, and the worst, surprisingly the eccentricities were unexpectedly large.

There is a tendency to believe that a nominally symmetric building cannot respond in a torsion mode of vibration. This is a naive expectation. Actually, buildings are not perfectly symmetric and as some researchers (DeLaLlera and Chopra, 1994) have shown before, accidental eccentricity and rotational components of the ground motions induce torsional response in symmetric buildings. Dissertation Format

Therefore, we must be prepared to confront this truth: all buildings will respond in torsion during a seismic event, thus we need to know how to evaluate its magnitude and how to control its effects in a rational and reliable way.