Deep Injection (UDI)

Settled pavement, a dipping foundation, or a structure that has started to tilt usually points to one thing: the soil underneath has lost strength. URETEK Deep Injection® (UDI) is a patented, high-density polyurethane injection process that densifies that soil and lifts what sits on top of it back toward its original position. Engineers, private owners, and public agencies use it on roads, runways, foundations, and structures that can't be closed for a full rebuild.

Problems Deep Injection (UDI) Solves

Weak, settled soil doesn't stay a small problem. Here's what it leads to if it's left alone.

Settled or uneven pavement that creates a safety hazard for drivers, aircraft, or pedestrians

Foundations or slabs that have dipped, cracked, or pulled away from adjoining structures

Soft, low-density soil that can't carry the load of a road, building, or piece of heavy equipment

Subsurface voids beneath pavement or structures that keep growing until the surface gives way

Key Signs You Need Deep Injection (UDI)

Weak soil usually shows itself on the surface before it becomes an emergency. Watch for these.

A dip, depression, or wave in pavement that wasn't there before

Cracks radiating outward from one point on a slab, foundation, or roadway

A structure or slab that has visibly tilted or settled unevenly

A hollow sound or spongy feel when the ground is walked or driven over

Water pooling in one spot after rain, even on ground that should drain evenly

Joints or panels that no longer line up the way they did when built

Benefits of Deep Injection (UDI)

Why engineers and agencies choose UDI over excavation or full reconstruction.

Handles jobs from a single settled panel to a full runway. URETEK has used UDI to complete over 100,000 projects since 1989, on everything from local driveways to interstate highways and international airports.

Lowers the safety risk that comes with open excavation. Because holes are as small as 5/8 inch, crews aren't working inside a trench next to live traffic or unstable soil, which is the main safety hazard with dig-and-replace repair.

Keeps the road, runway, or facility open. At LAX, URETEK stabilized a terminal and runway section in a single overnight shift, and air traffic resumed on schedule the same morning with no extended closure.

Works nights, weekends, or holidays, and cures fast. URETEK 486 Star® cures to 99% of its strength in minutes, not days, so crews can mobilize on short notice and finish before the next operating shift begins.

Holds its strength even in wet or flowing groundwater. URETEK 486 Star® is hydro-insensitive and expands up to 20 times its original volume once injected, densifying soil that ordinary grout would wash out of before it could cure.

Why Choose Deep Injection (UDI)?

Deep Injection (UDI) is the right call when settled pavement, a dipping foundation, or a sinking structure needs to be lifted back toward grade, or when soil beneath a load simply needs more density and bearing capacity. It's URETEK's flagship, patented process and the one used across the widest range of projects, from highway panels to airport runways to building foundations.

It's not the right tool when the main goal is a water barrier rather than lifting or densifying soil; Curtain Grouting is built for that. It also isn't the first choice when the primary problem is a large, already-formed underground void with little load above it; Void Filling addresses that more directly. For fine-grained soils that need a low-viscosity grout to permeate small pore spaces rather than a high-density polymer, Permeation Grouting is the closer fit.

Deep Injection (UDI) is frequently paired with Concrete Leveling on the same project, since lifting a settled slab back to grade and densifying the soil beneath it are often part of the same repair.