Stabilizing soft clay soils and shallow utilities during the reconstruction of Main Street 

Overview

The town of Palisade, located in Mesa County, is known as the peach and wine capital of Colorado. The Town needed to rebuild its Main Street to keep up with the growing diversity and increased traffic load in an expedient and cost-effective manner. During the reconstruction of Main Street, soft soils and shallow utilities were expected to be encountered, creating challenging conditions for construction.

Challenge

The geotechnical investigation concluded soil characteristics would vary, with the first boring indicating a moist, dense, sandy gravel, and the remainder of the borings indicating a moist, soft to stiff, lean clay. Laboratory testing results indicated that the native clay soils were moderately plastic and tended to consolidate under loading at their existing density. The California Bearing Ratio (CBR) was determined to be less than 2%.

Solution

The benefits of utilizing geosynthetic-reduced sections on this project included both time and cost savings. The contractor installed MIRAFI® RSi-Series geotextiles with ease, maintaining a minimum of one foot of overlap. The geosynthetic-reinforced sections provided faster construction due to reduced excavation, less aggregate to transport and install, and not having to excavate into utilities. The expedited construction schedule equated to happier townspeople and shop owners.

Accounting for the reduction in excavation and the reduction of the aggregate section thicknesses, it is estimated that the geosynthetic-reinforced designs provided approximately $60,000 in cost savings. The engineer put his best foot forward in providing cost-saving options to the Town, and the Town put their best foot forward by utilizing the cost-saving designs, which saved taxpayer dollars.