ASCE-07-22 [1] presents wind load determination procedures on MWFRS mainly in Chapter 27 (Directional Procedure) and Chapter 28 (Envelope Procedure, typically for low-rise buildings), and on C&C in Chapter 30.


The determination of wind pressures requires consideration of both external and internal pressure coefficients. Table 26.13-1 of ASCE 7-22 provides internal pressure coefficients for buildings with different enclosure classifications. For each non-open building classification, the table specifies two values—one positive and one negative—and both must be considered.


Accordingly, for each wind direction (wind from the left, right, back, and front), two load cases are required, representing internal pressure acting toward and away from the interior surfaces (i.e., positive and negative internal pressure).

1- Wind from Left side with Negative internal pressure

2- Wind from Left side with Positive internal pressure

3- Wind from Right side with Negative internal pressure

4- Wind from Right side with Positive internal pressure

5- Wind from Front side with Negative internal pressure

6- Wind from Front side with Positive internal pressure

7- Wind from Back side with Negative internal pressure

8- Wind from Back side with Positive internal pressure


Therefore, MkaPEB considers 8 load cases for the determination of MWFRS wind loads (4 directions × 2 internal pressure signs) and 8 load cases for the determination of C&C wind loads.


References:

[1] American Society of Civil Engineers. "Minimum design loads and associated criteria for buildings and other structures." American Society of Civil Engineers, 2022.