Items 1 – 32: Base Slab, Riser Section, Reducer Slab, Concentric Top Cone, Eccentric Top Cone, Pedestal Tops, Flat Top Slab. Precast manholes and components are for use in gravity-flow storm water and sanitary sewer applications. All manholes and components shall conform to ASTM C478, latest edition. Size or dimensions are nominal inside diameter and shall be in general accordance with GADOT Standard Detail 1011A. Concrete strength shall be 4,000 PSI minimum. A manhole base section shall consist of a monolithically poured base slab with a riser of a determined height. Reducer slabs shall be designed for up to a 15-foot bury depth. Each manhole product shall be marked on an exterior section with a) Name of Manufacturer, and b) Date Manufactured. Marking shall be made by painting. Items 33 – 34: Catch Basin Top Slab and Catch Basin Spillway. Precast catch basin top slab and spillway shall conform to GADOT Standard Detail 1033D. Concrete strength shall be 4,000 PSI minimum. A light duty rated frame and cover of a gray iron casting conforming to ASTM A48, Class 35B shall be cast in the top slab. The frame shall have a nominal 24-inch diameter opening. The cover shall have the word “STORM” cast on top in letters two (2) inches high. Items 35 – 36: Catch Basin Top Slab and Catch Basin Spillway. Precast catch basin top slab and spillway shall conform to GADOT Standard Detail 1034D. Concrete strength shall be 4,000 PSI minimum. A light duty rated frame and cover of a gray iron casting conforming to ASTM A48, Class 35B shall be cast in the top slab. The frame shall have a nominal 24-inch diameter opening. The cover shall have the word “STORM” cast on top in letters two (2) inches high.
