Haward Baker has started work on a $9.1 million ground improvement contract for the K-10 South Lawrence Trafficway in Lawrence, Kan. The project will improve transportation infrastructure for the state of Kansas and is of high importance to the Kansas Department of Transportation (KDOT).

The project will finish the southern K-10 bypass from US 59 to the existing K-10 east of Lawrence. Haward Baker is a subcontractor to Emery Sapp & Sons Inc.

A subsurface investigation exposed weak alluvial and residual silt, clay and sand beneath the planned embankment. Based on laboratory tests of the underlying soft, compressible soil, it was predicted that the embankments would settle excessively and experience slope instability.

Hayward Baker proposed the installation of wick drains and construction of stone columns as a solution.

Additionally, four previously built embankments nearby had experienced surface failures. Analysis indicated that two of the planned embankments would also experience slope failures due to the weak subsurface conditions.

As a solution, Hayward Baker is building more than 6,800 36-inch diameter stone columns as deep as 62 feet. The construction will use more than 150,000 tons of aggregate and last up to seven months. 

The subsurface examinations also identified 26 planned embankment sites with consolidation periods of more than 10 years. Hayward Baker’s subsidiary, Hayward Baker Wick Drains, is installing approximately 42,000 wick drains to a maximum depth of 75 feet.

This will accelerate consolidation of the soils so that the settlement takes place before the final roadway construction. An installation rig with 60,000 pounds of static push force is being used. It will take and expected 20 weeks, non-consecutive, to install the drains. The consolidation time will shrink to less than 45 days.

Hayward Baker, a Keller Group company, has worked in ground modification and site improvement for 60 years, and offers a range of foundation support and rehabilitation services. For more information, visit www.haywardbaker.com.