Properties and Dynamic Behavior of Glass Curtain Walls with Split Screw Spline Mullions

Recent terrorist events have underscored the importance of designing glass curtain walls as engineered systems. For most building owners, however, it is usually an unjustifiable expense to have a curtain wall designed to provide a high level of blast resistance. This paper investigates the serviceability of an economical, nearly conventional, glass curtain wall system that provides a low level of blast resistance in appropriate applications. A conventional, split screw spline mullion system is utilized with laminated glass lites properly attached to the mullions with structural silicone sealant. The response of this system to service load conditions is first explored through static and dynamic experimental testing. A simple finite-element model of the system is then calibrated to low-amplitude static test results. Finally, the calibrated model is used to perform modal and transient analyses that are compared to experimental free vibration responses. The model was found to provide results that agree well with experimental responses, indicating that the primary properties have been adequately defined for reliable serviceability investigations.