How do steel push piers fix a settling foundation in Oklahoma?

Reviewed by Preston, Oklahoma foundation repair consultant · Updated 2026-10-14

In short: Steel push piers are sections of steel pipe driven straight down beside or under a footing with a hydraulic ram, using the weight of the house as the push-back force, until they reach soil or rock that resists the load ². The hydraulic pressure is recorded for every pier, giving a field record of drive resistance at installation. In one large set of Tulsa installation records the median depth was about 12 feet ³. Push piers carry downward load only; they do not stop swelling clay from lifting a foundation ².

How does the system work?

A pier is a column that carries a building's load down to firmer ground. A push pier (also called a resistance pier) is driven rather than drilled:

1. The soil is dug out at the footing and the footing face is prepared.
2. A steel bracket is attached to the footing or grade beam.
3. Pipe sections are pushed down through the bracket by a hydraulic ram. The ram pushes against the house, so the structure's weight is the reaction.
4. Pressure is read at each section. When the pier will not advance under the target force, it has reached its drive resistance.
5. Load is transferred to the piers, the foundation is lifted (often with several rams on one manifold so lifting is even), the pier is locked off and the hole backfilled.

ICC Evaluation Service publishes acceptance criteria (AC517) for push pier foundation systems, which set a method for establishing allowable load and deformation capacities for systems that resist axial compression ¹. Many systems are evaluated against these criteria; the specific capacity of a given system comes from its evaluation report and the engineer's design.

How deep do push piers go in Oklahoma?

Oklahoma installation records for 396 steel push piers at a large Tulsa site (2025) show ³:

The wide range reflects changes in soil, weathered shale and rock depth across one site. See depth to rock from borings and bedrock in the Tulsa metro.

What do push piers address?

Push piers are used where the foundation has settled — moved down — and firmer soil lies below the zone causing the movement. Typical cases include perimeter drying settlement, tree-root desiccation settlement, fill consolidation settlement and soft alluvial soils.

The aim is to bear below the active zone, the depth where soil moisture changes with the seasons. Oklahoma research using Mesonet data estimated active zone depths around the state at about 0.5 to 4 meters (roughly 1.5 to 13 feet) ⁴. Soils with an NRCS linear extensibility of 6% or more are rated high or very high shrink-swell ⁵.

What are the limitations?

Refusal is not a static load test

The recorded pressure shows how hard the pier resisted at the time it was driven. Engineering reviews of post-repair performance list two related problems with steel pipe piles: piles not driven deep enough, and loss of skin friction (side grip) at shallow depths during drought ². A pier that stops in stiff, dry clay or soft weathered shale near the surface may still be inside the active zone; see shale weathering and bearing strata.

No uplift resistance

Piers will not prevent uplift from heaving soil unless they are designed to do so; the same review notes heave is generally not considered a pier failure, though it can look like one ². For this reason push piers are not a fix for perimeter wetting heave or post-tree-removal heave. Where the center of a slab has heaved, piers are sometimes used only to raise low perimeter areas toward the high center after the water source is fixed.

Other installation problems

The same review lists piles installed out of plumb and overloading that bends the shaft as potential problems ². Other limits:

• The structure must be heavy enough to push against; light buildings may not develop enough force, which is one reason helical piers are used.
• The bracket sits beside the footing, so it loads the footing off-center; a weak or shallow footing limits what can be done.
• Buried steel corrodes. A long-running federal study of underground corrosion found the most corrosive soils were those with high soluble salts (low electrical resistivity) and poor aeration, such as wet, poorly drained clays ⁷.
• Where soluble rock and cavities are suspected, an engineering investigation comes before piering.

What records and follow-up are kept?

Each pier's depth and final pressure are recorded, and gauge pressure is converted to load using the ram area and calibrated gauges. Monitoring guidelines call for recording elevations at the same reference and monitor points used in earlier surveys, with drainage, plumbing leaks and other moisture problems remedied well before a monitoring period ⁶.

Cost is driven mainly by the number of piers, their depth and access to the footing.

Related

• Pressed Concrete Piles
• Helical Piers
• Loads, Pier Spacing and Capacity
• Pier Uplift or Movement After Repair
• Method Selection Matrix
• Lifting Procedure and Restoration