The first problem: Because the glass curtain wall is generally installed perpendicular to the ground, the direction of wind load and earthquake force is perpendicular to the curtain wall surface (that is, perpendicular to the bonding surface), while the direction of self-weight is parallel to the curtain wall surface (that is, along the bonding surface). The same is true of the curtain wall with horizontal inversion. The directions of gravity and horizontal force have not changed, but the glass surface has turned 90 degrees, so the two working conditions are just the opposite.

The second question: For the bonded joint, if it is subjected to shear force, generally only the web, that is, the length of the bonded joint in the direction perpendicular to the stressed section, can be considered if it is tensile force. This method is the same as the calculation assumption of other structural forms of I-beams, regardless of the long and short sides.