**7. Define earthquake Hazard**

Ground motion prediction equations provide estimates of spectral response acceleration parameters for specified earthquake magnitude and site-to-source distance based on regression analyses of past strong motion recordings.

Most ground motion prediction equations provide geometric mean (geomean) spectral response accelerations represented by the quantity:

$$\mathbf{S\_{gm}} = \sqrt{\mathbf{S\_x(T)} \* \mathbf{S\_y(T)}} \tag{1}$$

where *Sx* and *Sy* are orthogonal components of spectral response acceleration at period T. The *x* and *y* directions could represent the actual recorded orientations, or they could represent a rotated axis orientation.

Intensity-based assessments require a target acceleration response spectrum and suites of 11 pair of ground motions scaled for compatibility with this spectrum (see **Figure 25**). **Figure 26** represents the selected ground motion pairs with geomean spectra that are similar in shape to the target response spectrum.

To determine the building's fundamental translational periods in two orthogonal directions, modal analysis is performed. The fundamental periods in x- and ydirections are 1.94 sec. and 1.98 sec., respectively. Then, the average fundamental period of the building is considered as:

The collapse fragility is thus defined as having a median value of Sa(T) of 1.16 g and a dispersion of 0.6 as entered into the PACT Collapse Fragility panel

The number of independent collapse modes which can occur and thus the probability of each is difficult to predict analytically. To figure out these data, the user must use judgment supported upon building type, structural system, experience, and analytical inferences. When using the simplified analysis approach, limited analytical information regarding potential collapse modes is out there. For this instance, just one mode of collapse is taken under consideration. More information's gained from numerous response history analyses can give additional insight into

(**Figure 24**).

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**Figure 19.**

**Figure 18.**

*Electrical distribution.*

*Natural Hazards - Impacts, Adjustments and Resilience*

potential collapse modes.

*SAP2000 hinges application at beam.*

**Figure 22.** *SPO2IDA tool, SPO tab.*

$$\overline{T} = \frac{T\_x + T\_y}{2} = 1.96 \text{ sec} \tag{2}$$

fundamental period of the building, in the direction under consideration, for the selected level of ground shaking; and W1 is the first modal effective weight in the direction under consideration, taken as not less than 80% of the total weight, W. **Figures 27** and **28** and **Table 3** show the computed lateral displacement in X (2)

where *H<sup>Δ</sup><sup>i</sup> S*, *T*1, *hi* ð Þ , *H* is the drift modification factor for story *i* computed.

*T*<sup>1</sup> ¼ 1*:*96*s*, *H* ¼ 24*:*6*m*

Values of *a*<sup>0</sup> through *a*<sup>5</sup> for 6 stories or less in height are provided in [1] Table

*hi*þ<sup>1</sup> *H* <sup>2</sup>

*hi*þ<sup>1</sup> *<sup>H</sup>* <sup>þ</sup> *<sup>a</sup>*<sup>4</sup>

*<sup>i</sup>* ¼ *H<sup>Δ</sup><sup>i</sup> S*, *T*1, *hi* ð Þ� , *H Δ<sup>i</sup> i* ¼ 1*toN* (4)

*hi*þ<sup>1</sup> *H* <sup>3</sup>

, *S*≥ 1, *i* ¼ 1 *to N* (5)

þ *a*<sup>5</sup>

direction and the corresponding drift ratio.

*Performance-Based Design for Healthcare Facilities DOI: http://dx.doi.org/10.5772/intechopen.95320*

*ln H*ð Þ¼ *<sup>Δ</sup><sup>i</sup> a*<sup>0</sup> þ *a*1*T*<sup>1</sup> þ *a*2*S* þ *a*<sup>3</sup>

5-4 by using the strength ratio given by:

With

**245**

**Figure 23.**

*SPO2IDA tool, IDA tab.*

*Δ*∗
