Abstract: The use of the electric cable tunnel is different from that of metro tunnel, and also its inner loads. Based on Shanghai electric tunnel project, the structure inner force under inner and out loads was analyzed, and the calculating model should be used that have the ability to deal with changeable structure and varying loads. The analysis results show that, after the assembly of the cross beam and under corresponding inner loads, the axial force of shield tunnel segment increases; and the segment moment decreases in upper part, but increases in lower part; the moment that joint element bears decreases.
 

Key words: electric cable tunnel, changeable structure system, structure inner force