Project Description
This 20’ X 15’ century-old sewer was lined with 5000 psi, silica-fume modified, fiber and steel reinforced shotcrete and concrete. The structure was originally built of fitted limestone with a brick invert. Due to the confined spaces and large volume of material, the shotcrete was placed using the wet-mix process. Difficulties included diverting and by-passing the normal flow of the principal downtown St. Louis drainage tunnel so that work could be undertaken.