The invention discloses an underground
engineering mixed construction method which comprises the following steps that (1) the surface of a road is transversely divided into a section A, a section B and a section C, the section A is sealed,
reinforced concrete construction is carried out on the section A, and an underground continuous wall is obtained; (2) the
surface layer earthwork is excavated to obtain a
basement top slab of the section A; (3) earth is backfilled to recover the traffic of the road face of the section A; (4) the section B is sealed, and
reinforced concrete construction is carried out on the section B to obtain an underground continuous wall; (5) the surface earthwork is excavated to obtain a
basement top slab of the section B; (6) earth is backfilled to recover the traffic of the road face of the section B; (7) the section C is sealed, the surface earthwork is excavated, and
basement bottom slabs of the section A, the section B and the section C are obtained; (8) a basement top slab of the section C is obtained and connected with the top slab of the section A and the top slab of the section B; (9) earth is backfilled, and the road face traffic is recovered. By means of the underground
engineering mixed construction method, efficient and safe construction on the road face is achieved, bi-directional traffic is achieved, and the problems that a cover and
cut-top down method is limited by excavation depth and is low in excavation speed are solved.