Slabjacking and mudjacking cost depends on the stability of any structure or concrete slab is based largely on the properties of the soil it is built on.
When industrial, commercial, or residential structures settle, shift, and move, it can be the result of several soil-related circumstances that include: building on expansive clay, compressible or improperly compacted fill soils, or improper maintenance of the grounds around a foundation. When settlement occurs, it can destroy the value of the building and even render it unsafe. Traditional methods, such as cementitious grouting (often referred to as mudjacking), have provided less than ideal results and have been used in the past as a temporary solution to a long-term problem.
Early Concept and Technological Advancement
Although the concept and best practices behind traditional slab lifting and mudjacking methods are credible and still used today, the materials that are used with them often require lengthy installation times and do not stabilize the underlying soil, which is typically the source of the problem. As a result, these approaches (including “do it yourself mudjacking pumps”) yield a temporary fix which often result in a short life expectancy for the repair, and higher costs down the road to resolve on a more permanent basis.
The advancement of technology, knowledge, and specialized materials have vastly improved the speed, longevity, and effectiveness of concrete lifting and soil stabilization solutions often exposing many of the weaknesses of older concrete lifting methods such as mudjacking. For example, cementitious material is slow to cure, and as it hardens it also shrinks. Once the cementitious material cures, it lacks sufficient tensile strength for long-term effectiveness which is important on heavy dead loads and in particular, live loads and vibration.
How Mudjacking Works
Cementitious grouting involves the use of a water/soil/fly ash/cement mixture injected by hydraulic pressure into the intersection of the concrete and base soils. The two basic components, a measured amount of water and a cementitious/fly ash mixture, are thoroughly mixed in a batch mixer, dumped into a hopper and pumped under relatively low pressure by means of a positive displacement pump. The pump discharges into a flexible hose and the grout is injected through a pre-drilled 1/2” to 3” diameter hole using a special nozzle to inject the material between the slab and sub-base.
Common Mudjacking Hazards
According to the National Lime Association, the main danger in mudjacking is that plumbing lines can separate when it’s used to raise an interior slab. If a sewer line were to break, the slurry could enter the line and solidify before it could be cleaned out. Then the plumbing line would have to be broken out and replaced.
In addition, mudjacking sometimes acts as only a temporary repair. For the slurry to hold the concrete in position, the soil beneath must remain in place. If the soil were to dry out and sink, the slurry would sink with it and not be able to hold the load of the concrete above. Likewise, if water diversion is not addressed (or if the source of the subsurface water can’t be found), additional swelling or washout may occur, and the mudjacking repair may not hold. To make sure that your repair has the best chance of permanency, always follow the recommendations of your contractor.
Because the pumped in slurry takes the path of least resistance, it’s sometimes impossible to predict the results.
SOURCE: National Lime Association
Geo-Polymer Injection for Structural Stabilization
The use of high density expanding polymer for slab lifting was introduced in the United States in the early 1980’s by URETEK USA, Inc. The introduction of polymer technology revolutionized the concrete lifting industry by offering a faster, cleaner, highly controlled concrete lifting solution. URETEK’s concrete lifting process was conceptually the same as traditional mudjacking, but vastly different in technology, performance, and material capability.
How URETEK Geo-Polymer Works
URETEK’s geo-polyer technology is based on chemical expansion pressure, that is clean and environmentally neutral. The geo-polymer’s rapid cure time allows operators precise concrete leveling capability, virtually eliminating “overlift” or risk of foundation damage. The patented geo-polymer can be injected into a variety of saturated soil environments without losing compressive strength or structural integrity.
Watch URETEK in Action
URETEK Method® vs. Mudjacking Comparison
- Safe, low pressure injection of polymer under concrete slabs
- Rapid polymer expansion provides ultimate control for precise leveling.
- Material reaches 90% of strength in 15 minutes, asset can be used immediately
- Capable precision lifting, often to 1/8″ tolerance
- Small injection holes (5/8″) greatly reduces weakening the slab even more
- One time cost for permanent repair
- Improper mix design for applications in saturated soil environments
- Insufficient cure time (minimum 3 days, 7 days optimal)
- Constant vibration breaks the particulate bond of the slurry segregates paste and particles
- Additional weight of grout material over distressed base material diminishes any long term expectations
- Hydraulically pumped slurry is difficult to control, increasing the risk of concrete breakage or over lifting
URETEK Environmental Impact
The URETEK 486 Star/684 Material has been extensively tested by independent laboratories to meet EPA Standard Environmental tests. The results show that all URETEK 486 Star/684 Star polymer-resin materials are environmentally benign and have no detrimental effect to ground soils as a result of either decomposition or degradation of the polymer. URETEK polymer contributes to the LEED point system as material components used in URETEK 684/486 polymer use rapidly renewable materials. In addition, its use does not lead to the pollution of surrounding groundwater supplies and several of the 486STAR materials carry NSF 61 certification.
NSF/ANSI 61 Certification
NSF/ANSI Standard 61 – Drinking Water System Components was published in 1988 to establish minimum requirements for the control of potential adverse human health effects from products that contact drinking water.
Once the URETEK expanding polymer material has been fully cured and hardened to a rigid form, it becomes inert, chemically neutral and does not contribute to soil or water contamination, leaching, or pollution.The material is also impervious to mildew and fungi and neither appeals to or provides nourishment for insects or rodents. When exposed to sunlight, ultraviolet rays cause a yellowing of the foam and a slight pitting of the hardened surface, which poses no environmental threat. In addition, the chemical and solvent resistance qualities of the URETEK polymer material are quite good, and its ability to resist grease and oil is excellent.
Cost and Value Considerations
The short and long term cost of any concrete lifting and/or stabilization repair requires additional client understanding.
First, each job is different and requires a thorough evaluation to determine what has caused the problem and what material requirements will be needed to effectively realign and stabilize the concrete asset. For example, a broken water main beneath a facility will typically create a larger amount of void than years of vibration from machinery slowly causing the foundation to settle. Both situations from the surface may appear to have similar settlement characteristics but the urgency and liability can be far greater if a large unseen void causes concrete to buckle and cave in. Second, a client must evaluate the upfront costs for the repair in addition to any loss of revenue during the time that area cannot be accessed for commerce. For example, let us assume a facility loses $50,000 a day because unstable concrete prohibits access to merchandise racks. To break out and replace the concrete in this area will take 3 days and cost $10,000 which will ultimately cost the customer $160,000 (($50,000 x 3 days downtime) + $10,000 job cost = $160,000). URETEK typically can complete a project in one day, sometimes in hours and the client is able to access the repaired area immediately. Let’s assume the cost for the URETEK repair is $25,000 and the project takes a day to complete. The the total cost to the customer is $75,000 ($25,000 job costs + ($50,000 1-day loss)= $75,000). URETEK provides the customer a permanent solution while the total project price is a little more than 50% less than mudjacking or replacement. Third, materials used for both mudjacking and URETEK solutions are considerably different and have different price points. For example, cementitious grout material is typically less expensive than geo-polymer. However, the temporary repair status of mudjacking will eventually require the customer to mudjack the same location again, adding to the ultimate long term costs to keep the section of facility open. Lastly, a client’s decision on a solution can impact both short and long term costs greatly. For example, if a customer postpones maintenance on a concrete foundation until it has to be removed and replaced, the costs associated can be quite high considering all costs involved. The initial cost, the loss revenue because of facility shutdown, and environmental disposal fees are all considered. When all the components of a concrete repair are considered, preventative concrete maintenance solutions, such as URETEK’s structural polymer, will save a facility owner thousands, if not hundreds of thousands of dollars in the long term.
As the latest development in the evolution of slab jacking, The URETEK Method® provides a cost effective, fast, and safe solution to for the stabilization, repair, lifting,and restoration of a variety of industrial, commercial, and residential assets. As a pioneer and industry inventor, URETEK ICR delivers a “no disruption” cure for repairing a variety of asset settlement and stabilization problems such as sunken loading docks, warehouse floors, building foundations, and concrete slabs.
With the URETEK Method®, owners of industrial, commercial, and residential properties can make the most cost effective use of limited budget resources while dramatically improving the quality and longevity of their existing concrete assets. In addition, the rapid cure rate of the patented URETEK 486 Star/684 Star polymer material used in the URETEK Method®, accelerates the repair of settled or depressed concrete assets, minimizes work disruption and restores the asset to full use in a fraction of the time required with other traditional repair and maintenance methods.
URETEK ICR is associated with an international network of URETEK companies located in 80 countries, with exclusive rights in the United States to international patented technologies. Globally, URETEK companies have completed over 100,000 successful jobs, and utilize over 30 years of real world project experience. URETEK ICR focuses on resolving complex concrete lifting, soil stabilization and infrastructure rehabilitation projects for industrial, commercial, and residential properties, infrastructures, and assets.Ask URETEK