Design, Fabrication, Modeling and Experimental Study of a Totally Precast Concrete Counterfort Retaining Wall System for Highways

摘要

The overall structural behavior of a Totally Prefabricated Precast Concrete Counterfort Retaining Wall System (TPCCRW) was examined experimentally and analytically using Nonlinear Finite Element Analysis (NLFEA).The 20 ft. high, 13ft-10in. wide full scale TPCCRW prototype was designed meeting the requirements of AASHTO LRFD1 and manufactured in the precast concrete plant of Utility Concrete Product, LLC in Morris, Illinois. The design was optimized and validated using NLFEA. The wall consisting of face-panel and 3 counterforts were fabricated as a single entity and assembled with the precast base-slab in the field. The key elements were 5 headed anchors extended from each counterfort and grouted in the base-slab through shear pockets to ensure full connectivity between precast components.rnTPCCRW was tested experimentally by soil backfilling followed by applying load reaching 192 kips using hydraulic cylinders. The deflection at the face-panel and strain in concrete and steel were instrumented using 7 LVDTs and 45 strain gauges, respectively. The wall experienced a deflection of 0.2 in at its mid-height. The anchors, being the most critical component, succeeded to maintain serviceability and ultimate strength requirements. The furthermost anchors yielded without affecting the overturning and stability requirements at ultimate load. TPCCRW system has proved to be an innovative solution for multiple requirements such as speed of construction, strength, durability, safety and cost.