Toward Damage Free Residential Houses Through UniBody Light-Frame Construction with Seismic Isolation

While light-frame residential house construction generally performs well with respect to life safety, experience from past earthquakes indicates that widespread damage to houses can lead to large financial losses. The damage and losses are not entirely unexpected, owing to prevailing design philosophies that advocate reduced earthquake design forces through the use of ductile seismic systems. In contrast to current approaches, a new seismic design methodology is proposed to reduce deformations and damage through an enhanced strength/stiffness limited ductility light-frame shear wall system. The increased strength and stiffness is achieved by fully engaging all available interior and exterior walls to create a unibody system. Full-scale tests and analyses of component and system assemblies are presented to demonstrate ways to economically achieve enhanced wall strength and stiffness through the use of construction adhesive to attach gypsum wallboard sheathing and improved screw connectors to attach exterior stucco cladding. Component tests utilizing the limited ductility approach have demonstrated ultimate strengths of 1.3 to 1.5 kips/ft for interior walls with twosided gypsum boards, and as large as 2.4 kips/ft for a