TEMPERATURE CHANGES AND THERMAL STRESSES OBTAINED DURING COSTRUCTION OF IMMERSED-TYPE TUNNEL

Abstract

Osaka Nanko Tunnel is being built using immersed-tube elements. The elements are composite structures of steel and concrete, the concrete of which is classifiable as mass concrete, as it is more than 1m thick. Consequently there was concern that thermal stresses occurring during fabrication could lead to cracking in the concrete. This paper deals with the results obtained from the measurement of thermal stress. The ratio of restriction was calculated using measured values, and, by means of comparisons with existing measured data and data published by American Concrete Institute, the determination of the ratio of restriction in steel-concrete composite structures was studied.