**1. Introduction**

Indian subcontinent is a region experiencing seismic activities since ancient times. According to BIS seismic zoning map, over 65% of the country is prone to earthquakes of intensity MSK VII or more, putting 38 cities in high risk zones. In 2011, there were 80 earthquakes in India, with magnitude ranges between 3.5 M to 6.5 M on Richter scale. The year 2012 was an equally eventful year with 19 earthquakes by 5th March. Great earthquake having magnitude of 8.0 M or higher occurs somewhere in the world every year. Seismic engineering of structures is in discussion since decades while the aspects of risk mitigation and hazard assessment are relatively new in this field which are in concern with our preparedness for future events. The aim of a structural design engineer is always the safety as against the sole aim of economy. However, architectural needs and budget compromises the higher target of an engineer to bring resilience as an important consideration in design of buildings in seismic prone regions. The code provisions give legal benefit to developers while the resilience aspects highlight the need to bring better scientific methods to safeguard the community during strong earthquakes. With the advancement in knowledge and promotion of performance-based design procedures, it has become possible to safeguard our interests against the fury of nature.

The Bhuj earthquake (2001), had caused severe damage to property and more than 20,000 people were killed in Kuchchh area [1]. The reported PGA of the earthquake was 0.38 g having magnitude 7.7 Mw. Around 70 multistorey buildings collapsed in Ahmedabad, with reported PGA of 0.1 g for which the damage observed was higher than expected. Hence, the influence of present process of design of buildings on the performance of RC structures needs further check. There is another significant parameter for design consideration - the accurate hazard estimation. The observed damages better indicate hazard than the PGA values especially for mid-high rise buildings. The attenuation in Ahmedabad city is found to be around 1.8–2.0 [2], not considered in design. This is the serious limitation of force-based design wherein inaccurate estimate of hazard will give a sense of design to the engineer but is a gross-error in seismic design force calculations.

**2. Methodology**

**2.1 Problem description**

*Natural Hazards - Impacts, Adjustments and Resilience DOI: http://dx.doi.org/10.5772/intechopen.94303*

**2.2 Literature review**

**Figure 1.**

**213**

*Scheme for performance-based design method for standardization.*

A fifteen storey reinforced concrete building located in Ahmedabad city of Gujarat state is to be designed using Indian Standards (IS 456; IS 1893). The performance of this force-based design building will be evaluated using displacementbased method for performance-based design (PBD) using the procedures men-

The building design code for earthquake was first developed in Japan to consider 10% of dead weight as the lateral load. The code procedure developed based on understanding of severe damages in strong earthquakes around the globe [4]. Seismic risk mitigation is dependent on understanding exposure and vulnerability apart from seismic hazard for which effective design provisions are required for built environment to sustain the next event [5]. The present codes include the cyclic behavior through simpler procedures for performance-based design of building structures with reduced vulnerability [6–9]. TEC-2007 has been upgraded to

tioned in **Figure 1**. The plan and section details are given in **Figure 2**.

The expression of risk gives a good overview of each part that contributes to either the safety or to the weakness. In the equation, the term Hazard (H) represents the severity of earthquake expected in the region considered for risk estimation (refer Eq. (1)).

$$\text{Risk} = \text{Hazzard} \,(\text{H}) \times \text{Vulnerability} \,(\text{V}) \times \text{Exposure} \,(\text{E}) / \text{Asset} \tag{1}$$

If the estimation of hazard is an under-estimate, then the risk increases substantially, though the design may be done with utmost care. Seismic micro-zonation of Ahmedabad gives understanding of hazard to design engineers.

The building typology and design methods followed in a region suggest vulnerability aspects. Without disturbing the cultural heritage of local region, the capacity of existing buildings can be increased to reduce the quantum of vulnerable stock to various intensities of earthquake likely to hit there [3]. The role of developer, owner and administration plays a vital role in upgradation of vulnerable facilities and investing efforts towards the mitigation of earthquake hazard by identifying the vulnerability (V) component in a region. The density of buildings in an area, important structures, and the type of facility under threat is covered by the risk as the exposure or asset (E) parameter to estimate the threat susceptibility. The impact of earthquakes in India show the concern due to recent earthquakes (2001;2005) on the number of people succumbed due to lesser engineering (refer **Table 1**).

Hence, if we are better able to know our region, dedicated in identifying weak structures for upgradation and protect the important assets by identifying their importance, we can control the impact of earthquakes on our habitat. This study focuses on adopting resilience in mid-rise buildings using design tools.


#### **Table 1.** *List of severe earthquakes in India (7 Mw): Magnitude-PGA-intensity.*
