**9. Estimate median residual story drift ratio and dispersion**

Since the requirements for direct simulation of residual drift are computationally complex and not practical for general implementation in design, the following equations were developed to estimate the median residual drift ratio, response of the structure:

$$
\Delta\_{\mathbf{r}} = \mathbf{0} \text{ for } \Delta \le \Delta\_{\mathbf{y}}
$$

$$
\{\Delta\_{\mathbf{r}} = 0.3 (\Delta - \Delta\_{\mathbf{y}}) \text{ for } \Delta\_{\mathbf{y}} < \Delta < 4\Delta\_{\mathbf{y}}\} \}\tag{12}
$$

$$
\Delta\_{\mathbf{r}} = \left(\Delta - 3\Delta\_{\mathbf{y}}\right) \text{ for } \Delta \ge 4\Delta\_{\mathbf{y}}\}
$$

where Δ is the median story drift ratio calculated by analysis, and Δ *y* is the median story drift ratio calculated at yield.

The peak transient drift ratios were estimated. The yield drift ratio is obtained from the capacity curve derived from the pushover analysis used to generate the story shear at yield (**Figure 29**).

At yield, the peak transient acceleration is determined by the equation for the building fundamental period between the range of 0.7 sec to 2 sec:

$$\mathbf{S}\_{\mathbf{a}}(T) = \frac{\mathbf{S}\_{\mathbf{a}}(\mathbf{1})}{T} = \mathbf{0}.755 \mathbf{g} \tag{13}$$

From the capacity curve, the corresponding roof displacement for the peak transient acceleration at yield then is 0.0045 m. Thus, the yield drift ratio is:

$$
\Delta\_{\circ} = \frac{0.0045}{24.6} = 0.0002 \tag{14}
$$

The maximum transient drift ratio for the building occurs at the first story (*Δ*= 0.0090).

$$\Delta\_r = (0.0090 \text{--} \text{3} \ast 0.0002) = 0.0084$$

**Figure 29.** *Capacity curve from pushover analysis.*

*βSD* ¼

**Figure 28.** *X-X deformed shape.*

**Table 4.**

**Table 5.**

**248**

*Median story drift ratio estimates.*

*Natural Hazards - Impacts, Adjustments and Resilience*

*Median floor acceleration estimates.*

*βFA* ¼

*βFV* ¼

q

**Story Δi hi + l/H lnHΔi HΔi Δ\*i** 0.0073043 0.1869919 0.2089634 1.2323998 0.0090019 0.006275 0.3495935 �0.009875 0.990174 0.0062133 0.00595 0.5121951 �0.107092 0.8984431 0.0053457 0.00595 0.6747967 �0.082688 0.9206379 0.0054778 0.004075 0.8373984 0.0633358 1.0653845 0.0043414 0.003325 1 0.3309807 1.3923329 0.0046295

**Story PGA hi + 1/H lnHai Hai a\*i** 0.695 ——— 0.695 0.695 0.1869919 �0.357947 0.69911 0.4858814 0.695 0.3495935 �0.364289 0.6946906 0.48281 0.695 0.5121951 �0.37063 0.6902992 0.4797579 0.695 0.6747967 �0.376972 0.6859355 0.4767252 0.695 0.8373984 �0.383313 0.6815995 0.4737116 roof 0.695 1 �0.389655 0.6772908 0.4707171

q

q

ffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffi *βa<sup>Δ</sup>*

ffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffi *<sup>β</sup>aa*<sup>2</sup> <sup>þ</sup> *<sup>β</sup><sup>m</sup>*

ffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffi *βa<sup>Δ</sup>*

<sup>2</sup> <sup>þ</sup> *<sup>β</sup><sup>m</sup>* 2

<sup>2</sup> <sup>þ</sup> *<sup>β</sup><sup>m</sup>* 2

2

(9)

(10)

(11)

The median estimate of residual drift obtained from the simplified analysis method is assigned a dispersion of 0.8.

contained in the building model. A Monte Carlo procedure is used to assess a range

As showed in the **Figure 32**, the estimated median repair cost is shown as \$2.710.445, which corresponds to 8.37% of the building's total replacement cost. From the isograph on the **Figure 32**, it is seen that the yellow stick representing the performance group B2022.001 (Curtain Walls - Generic Midrise Stick-Built Curtain wall, Config: Monolithic, Lamination: Unknown, Glass Type: Unknown,

of possible outcomes as repair cost and repair time.

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

**11. Review results and comments**

**Figure 32.** *PACT repair cost tab.*

**Figure 33.**

**251**

*PACT repair cost graph.*
