Load transfer efficiency at joints and cracks in several airports has been measured by nondestructive testing apparatus. Repeated loading tests have been also conducted at cracks in continuously reinforced concrete pavement to make sure the durability of the load transfer mechanism, namely aggregate interlocking.
　The load transfer efficiency is not used directly in the designmethod as concrete slab thickness is decided based on the concrete stress in case of interior loading condition with suitable safety factor. To incorporate the survey result on the load transfer into the thickness calculation method, new design method has been developed. Both concrete stress caused by temperature changes and fatigue characteristics of concrete are taken into consideration in this method. Compared with the current design method, the new calculation method provides nearly the same slab thickness.