Abstract: A door lock can include a latch housing and a movable hasp. The latch housing can be configured to be secured with a door. The movable hasp can engage a catch secured to a door frame. The latch is movable relative to latch housing between an engaged position blocking against movement of the door and a disengaged position allowing movement of the door. Penetration through the door can be aligned with a sensor of the door lock to permit monitoring.

Abstract: A cyclic shear energy absorber is described for absorbing energy imposed onto the absorber. The absorber consists of a hollow core filled with densely packed granular material. The granular material is confined within the core so that cyclic shear energy imposed upon the absorber causes incipient dilation of the granular material. This incipient dilation is at least in part suppressed by the confining means. Inter-particle frictional forces within the granular material dissipate the imposed cyclic shear energy. The absorber may be confined between two end plates capable of being coupled to an associated structure such as a bridge support column and a base. The core may also be confined within a pile.