American Furniture Warehouse Slab Stabilization – Longmont, CO

Concrete Stabilization Technologies was contacted by Opus Northwest, LLC, concerning American Furniture Warehouse’s Longmont Colorado distribution location. The distribution warehouse was experiencing problems with the facility’s floor slabs. The warehouse floor slabs had deflection at the construction control joints caused by slab curl. When the edges or corners of a slab curl up, often at construction joints, it’s caused by concrete at the top of the slab shrinking or contracting faster than concrete at the bottom. Drying shrinkage is the usual cause. Water leaves the top surface of the slab faster than it leaves the bottom, creating shrinkage forces that can raise slab edges or corners.

CST used a dial gauge micrometer at the construction control joints to monitor slab deflection during load transfer from fork-lift traffic. Slab deflection was approximately 1/8” prior to slab under sealing and stabilization with CST expanding structural polymer. The uneven floor slabs were causing excessive wear and tear to the facilities forklift and loading equipment used on a daily basis in the warehouse and also creating a trip hazard for employees working in the facility. It was determined that 222 of the warehouse floor slabs, approximately 50,000 square feet of floor, would need to be stabilized.

Stabilization of the warehouse slabs began with crews mapping out, drilling, and placing 5/8 Inch injection probes through the concrete slabs.

CST polymer was injected in a pattern of every 4 feet below the slabs, filling voids, stabilizing, and providing a positive seal between the underlying soils and the concrete slabs.

Different sections of the warehouse floor area were stabilized over the course of the next eight days. Slab deflection was tested with forklift traffic after CST polymer injections. Zero movement on the dial gauge micrometer verified that the slabs were completely stabilized, thus extending the service life of the existing slab. On the five year inspection in November of 2014, no additional settlement or deflection has occurred since CST completed the stabilization of the Longmont American Furniture Ware-house in June of 2009.

Benefits of Slab Stabilization & Under Sealing using CST Expanding Structural Polymers:

  • Eliminates high costs associated with tearing out and replacing faulted concrete.
  • Provides a positive seal between underlying soils and existing concrete slabs, stabilizing and increasing the use life of the existing concrete.
  • Little to no disruption to business operations. CST polymer cures quickly, within approximately 15 minutes after injection. This allows for full use of the treated areas, immediately after repairs are completed.
  • State of the art equipment and highly trained technicians provide quick, clean, and surgically precise repairs.
  • Long lasting, environmentally safe, hydro-insensitive material has no negative impact on surrounding soils or adjacent water supplies.
  • High resistance to manufacturing chemicals and oils.
  • Puts businesses in control of repair and restoration requirements of problems associated with industrial, commercial, and residential concrete assets.

LDS Meeting House – Malta, ID

The Church of Jesus Christ of Latter Day Saints Second Ward Meeting House, located in Malta Idaho, had been foundation settlement and movement in portions of the building, resulting in ongoing damage to the structure.

In the spring of 2014, LDS structural engineer, Chris Barker contacted CST’s Utah Field Consultant, Jonathan George, concerning a repair plan for the structure.

Malta Idaho is a small community located in south central Idaho. Agriculture is one of the main industries in this area. Water being pulled from aquifers for irrigation throughout the area has lowered the water table. With change to the ground water and water table below the surface, pressure areas change and shifting of soil and rock below the surface take place. Sometimes, this occurs at depths very far below the surface.

Engineering reports indicated that settlement and shifting of the soils at a considerable depth, as suspected, were likely the cause of the extensive foundation settlement and sideways movement occurring at the LDS building.

A measuring device which had been installed on the building in early spring of 2014 showed movement of 3 millimeters over a period of 4-5 months.

CST met with the LDS maintenance personnel on site and performed investigative Dynamic Cone Penetrometer tests.

Test results determined that most of the settlement was not related to the upper 15 feet of soils, lending support to the conclusion that movement was coming from considerable depth.

After a thorough site investigation and analysis of soil tests, CST proposed to employ the CST deep injection method in order to lift and stabilize the building’s foundation both around the perimeter of the building and the load bearing footers and walls on the interior. DCP tests verified soil conditions in order to create an engineered plan to address the weaker zone of soils.

Soils directly below the foundation were dry and ideal for effectively lifting and stabilizing the structure to mitigate future movement and damage.

On May 5, 2015 CST crews arrived on site. A walkthrough was made to identify all crack openings and other damage that had been caused by the settlement and sideways movement of the building. CST’s crew members began drilling injection holes on the exterior of the building near the foundation to identify the spread footer. Probes were then placed on 4 foot centers approximately 3’ to 4’ below the spread footer. Other members of the crew began drilling and preparing interior injection holes and probes and drafting the exterior survey.

On day two, crews prepared equipment to begin injections and starting on the west exterior corner, technicians began injecting structural polymer at set locations. The foundation responded and began moving quickly. Some of the exist-ing cracks began to close at this point. Crews moved back and forth in the west corner section until a total lift of 3 ½ inches was accomplished on the exterior portion of the foundation.

On the final day, crews moved to the interior of the building and complete injections to lift the slab to target elevation.

Result: The load bearing wall was lifted, stabilized and void fill completed in the treated areas. As a result, existing cracks were closed in damaged areas. Movement of the building was greatly arrested and mitigated against further structural damage. All work was completed in three shifts.

Benefit: The CST technologies require no excavation and are performed with very little disturbance or mess. Repairs are made in days, not weeks or months. No need to vacate buildings and treated areas may be used immediately following repairs.

Liquor Warehouse Slab Lift – Cheyenne, WY

The Customer

Built in 1976 over an old creek bed, this warehouse once served as an electronics distribution center for over 20 years. It now is the sole storage and distribution hub for imported liquor in the State of Wyoming.

In 2012, the State of Wyoming purchased a warehouse that was used as an electronics distribution center for over 20 years, turning the facility into a storage hub stocking Wyoming’s liquor inventory for statewide distribution.

Shortly after the state purchased the warehouse, installation of newer, higher shelving was erected to store over $18 million worth of liquor inventory. The shelving exceeded 15 feet in height allowing additional inventory to be stored for future statewide distribution.

The Challenge

Soon after liquor inventory was stocked on the warehouse shelves, warehouse managers noticed cracks appearing and growing larger in the floor slab. The additional weight from liquor inventory combined with constant pounding and vibration from forklift traffic expedited the weakening of the sub-base and floors. Warehouse management quickly recognized the topple hazard of the uneven shelving and trip hazards created by uneven floor slabs, as a huge safety concern for employees working in the facility.

After a complete evaluation of the pre-construction and existing conditions of the warehouse, results showed 1) numerous areas of differential settlement in the slab, 2) high spots caused by poor finishing techniques, 3) unraveling joints in several locations, and 4) cracks in the concrete slab ranging from hairline to 1/4” in width.

The Solution

With the goal to improve the ride and extend the useful life of the warehouse floor, the following solutions were applied to treat 12,000 square feet of warehouse floor:

  • The CST method was used to underseal, stabilize, and realign mismatched and uneven slabs
  • Joint sealing and crack repair to protect surface
  • Grinding/smoothing high spots in rolled joints
  • Remove and replace unrepairable concrete sections

The Results

Concrete Stabilization Technologies successfully treated approximately 12,000 square feet of warehouse flooring. CST completed the undersealing, slab lifting and realignment, and overall stabilization of the entire warehouse floor in 3 ½ days.

In addition to CST injections, approximately 6,300 square feet of concrete was ground down and a special concrete hardener was applied to protect the surface from future damage.

Timely completion of the warehouse stabilization allowed this important liquor inventory distribution hub to continue operations with minimal disruption and downtime.

Jefferson High Foundation Settlement – Edgewater, CO

Concrete Stabilization Technologies, Inc. worked with General Contractor Saunders Construction, on the Jefferson High School Remodel project, to stabilize soils and lift slabs in nine classrooms, a hallway, and a bathroom.  The work included cutting L-shapes  in carpet as required for injection holes, drilling of holes, testing, injection to stabilize soil & fill voids, grouting injection holes, and re-gluing carpet and replacement of any damaged tiles caused by drilling.

The work was scheduled to allow approximately 10 days to complete.

By lifting one of the classroom slabs back to original, it also realigned the cabinets along a wall   in one of the classrooms which is one  added benefit we commonly see when doing this type of  repair:  doors open and shut properly, cracks in walls close up, shelving becomes level again, etc.

The project was completed in four days vs. the ten day window for the work.  The stabilization work was completed with minimal disturbance to the facility, in half of the allotted time and under budget!  A major advantage of the CST technologies is the non-invasive and fast, clean nature of the processes. Schools, Hospitals, Shopping Centers, and other Public Use buildings are typically repaired and put immediately back into use in a matter of days vs. weeks or months.  This makes an ideal solution for projects needing to be completed over Holiday and Summer breaks or during off hours with no loss of use.

Distribution Warehouse, Slab Stabilization and Joint Fill – Pueblo, CO

A large retailer distribution center, a 1,270,000 square feet warehouse and storage facility located in Pueblo Colorado, underwent a large renovation and rehabilitation project in September of 2015. The building was acquired in 1986 and has had several additions to the original warehouse area.

The Problem

In July of 2015 a site survey revealed a large array of structural deficiencies including drainage issues, spalling issues of interi- or concrete surfaces, water infiltration, settlement of concrete floor slabs, building movement, problems with doors not shutting, cracking in the precast wall panels above bay doors, and joint filler deterioration. Roche Constructors, a highly reputable Commercial Contractor located in Greeley Colorado was awarded the contract to coordinate and provide rehabilitation of the building. CST partnered with Roche to perform the slab lifting, soil stabilization, structural repair and joint filler portions of work.

Settlement of close to 6,000 square feet of floor slab had created a bird bath in the main north/south runway at the east side of the building near the busiest loading dock bays. This area is continually pounded by loaded forklifts carrying product to and from storage areas. Soil testing determined a weak soil zone 10 to 12 feet below the slab in this area that likely contributed to the settlement. The joint sealant in the control joints in a large portion of the floor slabs had lost cohesion and needed to be replaced as well.

15 areas in the precast walls located above the large overhead dock doors had developed cracks due to impacts from large semis unloading freight.

Factors for Consideration

There were many factors CST had to consider while planning and executing the stabilization and repairs of the distribution center. Roughly 25% of the floor area that needed lifting was in the main runway. Injection hoses would need to be run along this area, but not interfere with forklift traffic. Due to the approaching holiday season, the warehouse was receiving more inventory than usual and areas had to be accessible for unloading and storing freight. Because of increased shipments and need for access to the additional storage areas, the work window was reduced to accommodate receiving personnel and provide access to the additional storage areas of the warehouse.

The original joint fill compound used in the floor slab control joints had lost cohesion in a large portion of the slab area. In order to find the most effective and long lasting solution that wouldn’t require re-application, the product specified for sealing would need to be analyzed to ensure durability.

The sheer size of the warehouse itself posed a problem with communicating between crews and warehouse personnel. Two-way radios were issued which allowed easier communication when a question arose during repairs and attributed to a successful and smooth running project.

Method/Process Applied

The CST technologies were used to lift the warehouse floor slabs and stabilize the soils beneath the slabs. In addition, 3 columns were also stabilized and lifted to match the slab elevation. The CST process uses a high density expanding structural polymer that is injected through small probes into the soils below the concrete slabs. The polymer fills voids, increases bearing capacity of the soil, and lifts the concrete. Soils were also stabilized at depth of weakness to ensure no future settlement of the area. Careful monitoring at the surface was performed during injections to control the stabilization and lifting process with surgical accuracy. The CST soil stabilization and concrete slab lifting processes provide a permanent solution for settled concrete slabs because they treat the real problem, the underlying soils.

CST worked with the retailer’s engineering staff to determine a more effective and stronger compound than what was originally specified to ensure a more permanent adhesion and performance of the joint filler for the control joints. Areas were sectioned off and treated as to not disrupt warehouse traffic. Old material was removed from the joints, backer rod and sealer were then installed with areas marked off and allowed to cure before traffic was allowed back on the area which ensured good adhesion and strength of the treated joints.

To address the cracks in the precast walls , CST employed a composite repair system designed to provide shear and flexural strengthening to compromised and damaged buildings and infrastructure. The system uses an extremely strong carbon fiber matrix that was applied to the cracked and deteriorated areas of the precast walls. The repair system is significantly faster and less expensive than traditional repairs or replacement. Interior and exterior repairs were made to strengthen and protect the precast walls from further deterioration.

Result

The entire 6,000 SF slab area was lifted back to near original elevation and columns were stabilized and lifted to align with stabilized floor slabs, control joints were treated and filled and cracks in the precast walls were repaired in the time frame required. Soils beneath the distribution center warehouse were permanently stabilized, the concrete slabs and columns were realigned eliminating trip hazards and excessive wear and tear to equipment traveling over the areas. The structural integrity of the precast walls was restored. All processes were done with zero excavation and very little disturbance to the operations within the warehouse. Work was completed while leaving one lane open at all times to fork lift traffic. Due to the fast curing time and non-disruptive CST processes, traffic was allowed back onto the treated areas within 15 minutes following stabilization. The owner of this project and the owner’s representative, Roche Construction were very pleased with the professional, quality repairs performed by CST on the distribution center warehouse.

Soil Stabilization and Slab Lift

Dental Clinic Foundation Stabilization – Gillette, WY

The Problem

Unstable fill soil had resulted in settlement and movement of the Dental Specialists building foundation that threatened the structural integrity of the building and had caused cracking and gaps in window and door casings. Surveys detected upwards of 5-inches of settlement in areas of the foundation and interior concrete slab. Exterior sidewalk and curb/gutter areas had also experienced settlement causing uneven walking surfaces and trip hazards.

Factors for Consideration

The foundation lift and stabilization needed to be completed during a short window of time and in coordination with other contractors who would be working in the building at the same time. Dental and Orthodontic equipment, including sensitive X-Ray machines were present in the building and could not withstand large amounts of dust and debris. Additionally, carpeting over the concrete floor slabs in certain areas would need to be left in place during repairs in certain portions of the building.

Method/Process Applied

The unique CST technologies employ high-density expanding structural polymers to lift settled concrete foundations, slabs and other structures effectively, efficiently and economically. The soils are improved, voids are filled and poorly compacted soils are strengthened and permanently stabilizes using in-situ methodology.

Result

A thorough site survey was conducted measuring existing elevations and a surgically precise injection plan developed prior to injection of CST high-density expanding structural polymer. Complete lift of the interior floor slabs, foundation and curb/gutter areas was accomplished in only 3 shifts. Many of the existing gaps in window casings were closed during the process. The sensitive equipment in the dental offices was not disturbed and, due to the non-invasive processes, no carpet was removed and no landscaping disturbed. Due to the state of art injection equipment and no-dig technologies, CST crews were able to complete the foundation stabilization and concrete lift with no disruption to other contractors working on site.

Benefit

The settled foundation and floor slabs were efficiently and permanently lifted and stabilized, eliminating a very costly full scale repair. The existing structure and foundation were protected from any other damage. The dental office was able to re-open on schedule with zero disruption to their clients or business.