Office Building Slab Lifting & Soil Stabilization

The Challenge

4-inch settlement of office building slabs

An office building managed by CBRE was experiencing significant settlement of its interior slabs, with floors sinking by 4 inches. This presented safety concerns and operational challenges for the tenants. A key challenge was to address the issue without disrupting the office environment, as the work had to be performed in an active building.

Key Facts

The Solution

Deep soil stabilization and slab lift with expert collaboration

Groundworks began the project by conducting Dynamic Cone Penetration (DCP) tests at three locations to assess the extent of the soil instability. The tests revealed weak soil layers at depths ranging from 8 to 16 feet below the surface. To address these issues, Groundworks performed injections of high-density polyurethane at targeted depths of 9 feet, 12 feet, and 15 feet to densify the weak soil layers. Following this, a methodical slab lift was carried out to restore the floors to their original elevation. The repair process was guided by a design plan developed in collaboration with STSC Engineering, ensuring precision and effectiveness.

The Impact

Complete slab restoration with no office disruption.

The slabs were successfully lifted the full 4 inches, restoring them to their original position flush with the baseboards. The entire project was completed within 3 shifts over a weekend, eliminating any disturbance to office staff. This efficient, non-disruptive solution allowed the office building to maintain normal operations while resolving a major structural issue.