Polyurethane injection for roadways,
sidewalks, and municipal concrete.
Lift settled panels, fill the voids under them, and densify the soil that let them move, without removing and replacing the concrete. Most locations go back into service the same working day.
Who This Page Is For
The panel moved. The street still has to open.
Municipal and roadway concrete has a constraint residential work does not: the public is standing on it. This page is for public works teams, the contractors who bid their projects, and the facility managers carrying the same problem on private ground.
Public works and facility teams
You have a list of settled panels, a budget that does not stretch to replacement, and residents who notice every closure. Injection puts the concrete back and gives the lane back the same day.
General contractors on site work
When a punch list has a settled approach slab or a sunken dock apron on it, removal and replacement costs days you do not have. Injection is measured in hours.
Property and campus managers
Sidewalks, plazas, and parking areas settle where the fill under them was never compacted for the traffic they now carry. Lifting them in place keeps the surface and the schedule intact.
What We Do
Three jobs that get called one name.
Polyurethane injection covers lifting, void filling, and soil densification. Knowing which one a location needs is most of the value of the site walk.
What the material is
Polyurethane foam is formed on site from a two part mixture injected through holes as small as five eighths of an inch. It expands to many times its own volume, reaches most of its strength within minutes, and sets rigid, water resistant, and a fraction of the weight of concrete.
Lifting a slab
Small ports are drilled through the slab, foam is injected underneath, and the expanding foam raises the panel slowly and under control until it is back at grade. The holes are patched. The surface stays the surface you already have.
Filling voids
Water moving under pavement carries soil away and leaves voids. An unsupported panel does not fail politely, it cracks. Foam fills the void so the panel bears on something again.
Densifying loose soil
Deep injection puts material into weak or loose soil below the slab rather than immediately under it. That is soil densification, and it is the right answer when the slab is a symptom and the subgrade is the cause.
Why it suits roadway and sidewalk work
Foam sets quickly, so a lane or a walk can usually reopen the same working day. There is no spoil pile, no forms, no cure window before the surface takes traffic again. On a transit hub project the whole job started at eight in the morning and the site was cleared by four that afternoon.
Targeting the injection points
Where the subgrade is the suspect, penetrometer testing gives blow counts at fixed depth intervals. That turns an injection plan from a guess about where the weak material is into a map of it.
When injection is the wrong answer
Concrete that is broken into pieces, badly spalled, or structurally failed will not be fixed by lifting it. We will tell you that on the site walk rather than after the invoice.
The residential explainer on deep injection and soil densification covers the same chemistry and method in plainer language, concrete lifting and leveling covers the wider concrete scope at a smaller scale, and our commercial services page carries the rest of the work we do for general contractors and agencies.
Municipal polyurethane injection: see the method.
DCI's published case study of a transit hub where settled bus lanes were lifted by injection and the site went back into service the same working day. Replacement would have closed it for weeks.
A Municipal Example
A transit bus hub, back in service the same day.
DCI published this project as a case study, so the detail below is the client's own account of its own work.
A bus hub in Newport Beach run by the Orange County Transportation Authority had a differential crack running across both access lanes. The slab was twenty inches thick, the offset reached close to two inches in places, and there were voids between the concrete and the soil underneath. Buses weighing almost twenty tons arrived every fifteen minutes, dropping the concrete as they crossed the voided areas and making a bang loud enough to startle passengers.
The original plan was to remove and replace the concrete, which would have taken the stop out of service for months. Instead the work was done with staged polyurethane injections that densified the soils, filled the voids, and then lifted the slabs to take the differential out. Crews worked one lane at a time and moved between lanes inside the fifteen minute gaps, so the buses stayed on schedule. The cracks were filled with a DOT approved crack mender. The job started at eight in the morning and the site was cleared by four that afternoon.
"The third way is to do a polyurethane injection. That's the method that we use primarily, mainly because we don't scarify the concrete in grinding, exposing all the aggregate. It's a quick method, you can utilize the area right away, and it also densifies the soils below it a little bit as you do the compression, and that concrete actually pops back up and relevels itself."
How The Work Runs
Five steps around an open street.
Traffic control, work hours, and what has to stay open are part of the scope, not an afterthought.
- 01Walk the listSend the panel list, a site map, or just walk it with us. Injection scopes price per location and per condition, so the walk is what makes a number real.
- 02Written proposalLocations, the work at each one, exclusions, and a schedule. Warranty terms are provided in writing with the proposal.
- 03Traffic control and accessWho holds traffic control, which hours the work can happen in, and what has to stay open are settled before crews mobilize, not on the morning of.
- 04InjectionPorts are drilled, material is injected, elevations are watched as the slab moves, and the ports are patched behind the crew.
- 05Reopen and documentThe surface goes back into service the same working day in most cases, and the locations treated are documented for your records.
Scope And Submittals
What is in our scope, plainly.
Public work has more parties and more paperwork than private work. Here is where our line sits.
- Injection lifts, fills, and densifies. It does not replace a structurally failed slab.
- Night and weekend windows are scoped when the roadway or the site cannot close during the day.
- Elevations are watched during the lift so panels move together rather than one at a time.
- Tell us in the bid documents if the project is public works with certified payroll or prevailing wage requirements so the right terms are confirmed before award.
- Traffic control responsibility is stated in the proposal rather than assumed.
- Arizona work is performed under Arizona ROC license 330307, class KB-1, a dual commercial and residential classification.
What public works teams and GCs ask first.
Don't see your question here? Our team is happy to help. Reach out anytime.
In most cases the surface goes back into service the same working day. Polyurethane sets quickly, which is the main reason it gets specified over methods that need a cure window. The exact window goes in the proposal for your locations, not as a general promise.
Care and expertise from a team that's been doing this since 2011.
Dalinghaus Foundation Repair is locally owned and operated, with crews dedicated exclusively to foundation, concrete, and crawl space work across California, Arizona, and Nevada.
Foundation repair, concrete leveling, and crawl space repair are our entire focus. Not a sideline.
More than 2,000 projects on the clay and desert soils of California, Arizona, and Nevada since 2011.
CSLB License #983851 in California, ROC #330307 in Arizona, and License #0089738 in Nevada. Look us up with the state before we ever set foot on your property.
Warranty terms come in writing with every proposal, and the terms that apply to your job are stated in that job's paperwork. Ask your project specialist during the free evaluation.
Tell us about your commercial project.
Share the project address and the services you need, and add photos of the site if you have them. A member of our team will follow up.
Let's take the first step toward solid ground.
Tell us about the project, add photos of the site if you have them, and a project manager will follow up.