Abstract: A highway crash barrier structure with an improved interlocking system includes a plurality of rigid sections disposed end-to-end in interlocking relationship with one another. The ends of each rigid upright section are provided with a reshaped JJ Hooks® connection. Each hook member has an extending vertical lip which is bent into a “J” shaped cross-section to engage a similar lip on the hook member of the adjacent section such that lateral movement of the respective sections is prevented. However, the respective sections of the system can be easily placed or removed by vertically displacing them. In addition, the interlocking plates at each end of the upright sections are vertically lengthened while the number of bars welded to the plate is increased to reduce the rotational moment of the sections and increase shear transfer between adjacent sections.

Abstract: An improved post tensioning system for prefabricated building panels in which a concentric uniform radial compression is maintained in the slab. A post tensioning cable is placed in the concrete slab to form a perimeter loop starting from one corner of the slab to a point where the cable entered the slab and at a point turning 90.degree. to follow that portion of the cable in the periphery to a point midway up the Y axis and then turning 90.degree. across the X axis to bisect the slab and cross the opposite parallel portion of the cable to exit out the adjacent side of the slab. This creates a cable pattern with no less than 2.5 parallel cables in any direction.

Abstract: An improved post tensioning system for prefabricated building panels in which a concentric uniform radial compression is maintained in the slab. A post tensioning cable is placed in the concrete slab to form a perimeter loop starting from one corner of the slab to a point where the cable entered the slab and at a point turning 90.degree. to follow that portion of the cable in the periphery to a point midway up the Y axis and then turning 90.degree. across the X axis to bisect the slab and cross the opposite parallel portion of the cable to exit out the adjacent side of the slab. This creates a cable pattern with no less than 2.5 parallel cables in any direction.