Project Name: Lake Zurich Middle School, Lake Zurich, IL
Owner: School District 95
Scope: Underpinning Settled Structure
Lake Zurich Middle school began experiencing differential settlement of foundation walls and the interior floor slab immediately after construction was completed in 2003. During the schools original construction, a portion of the site was undercut and engineered fill was brought in and compacted in lifts. The engineer of record feels that this undercutting and compaction of fill was not done properly and contributed to the settlement of the structure.
The solution entailed installing 4 Atlas Resistance Piers (110,000 pound ultimate capacity) on the interior and exterior foundation walls to depths ranging from 45 to 70. Chance SS 150 (1.5 square shaft) helical piles with 8 and 10 flights (ultimate capacity of 40,000 pounds) were used to support the floor slabs.
The timeframe for completing this extensive scope of work was non-negotiable: the project had to be completed between June 9 and August 20. MixOnSite successfully installed more than 360 structural elements in just 45 working days, finishing the project seven days early!
Yorktown Center Lombard, IL
Stabilization of sinking sheet pile / precast wall
This newly constructed sheet pile/precast wall required stabilization when portions of the wall experienced settlement of more than six inches. Soil tests revealed a layer of fill that consisted of crushed limestone and fatty clay underlain by weak organic soils. The area of the wall that required stabilization was more than 120 in length.
Twenty micropiles, each with a capacity of 60 kips in design, were installed to bedrock (a depth of 80 feet). A steel I-beam was then used to connect the micro-piles and the sheet pile/precise wall, eliminating the potential for future settlement.
