Improved structure of twin-arch tunnel with composite middle partition wall

The utility model relates to the field of structural design of highway tunnels, in particular to a structural design of a twin-arch tunnel with a composite middle partition wall, which aims to solve the problems of the conventional twin-arch tunnel with an integral or composite middle partition wall that cracking in the fixing positions between primary supports and the middle partition wall is a common phenomenon, particularly for unsymmetrial loading tunnels and tunnels in soft and weak geologic zones, and that the cracking of secondary linings even happens to some twin-arch tunnels after the construction of the secondary linings. The structure is characterized in that the primary supports and the secondary linings of the conventional twin-arch tunnel with the composite middle partition wall are independently shaped into rings, and joints in the fixing positions between the middle partition wall and the primary supports or the secondary linings are removed. The utility model can facilitate the construction, guarantee the construction quality, and effectively prevent the cracking of the primary supports and the arch haunches of the secondary linings.