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Irrigation Head Gate Void Fill Erosion Control Soil Stabilization

Problem

Erosion of support soils beneath this concrete head gate had happened over time caused by turbulent water eroding soils beneath the inlet floors and undermining the structure. The voids created beneath the inlet had grown large enough that the foundation of the structure was compromised. In high water events, the undercut of the water could potentially wash out the entire head gate.
FC Excavation, the general contractor responsible for repair of the head gate was hired to provide a permanent solution to stop water from undercutting and carrying soil away from beneath the floor of the structure. An in situ solution, that would not require excavation or ripping out and replacing the concrete was preferred. They were also looking to make the repair during the fall when water was not being diverted through the head gate and have it solid before irrigation started in the Spring.

Solution

Concrete Stabilization Technologies partnered with Josh Frappart of FC Excavation in designing a permanent solution to fill voids and create an impermeable curtain wall beneath the head gate to support the structure and prevent future erosion.

Upon investigation of the site, it was discovered that voids as large as 2 cubic yards exist-ed beneath the head gate. To create a stronger base, the FC Excavation crew first added rock and soil into the large voids. Injections were then made into the soil, creating support pressure and filling the voids.

The hydro-insensitive expanding structural polymer (ESP) consolidates and strengthens the weak base soil and lenses out to fill voids, reinforces and densifies the soil, and creates a permanent barrier against water erosion.

Once the crew had finished injections, the contractor brought in rip rap to be placed on top of the repaired area.

Result

The entire repair of this undermined head gate was completed in 6 hours.

The expanding structural polymer installed by CST’s technicians efficiently and effectively rehabilitated this irrigation head gate with ZERO EXCAVATION.

The ESP used to repair the head gate will effectively mitigate against future erosion. The impervious barrier created beneath the structure will divert water from forming a channel beneath the head gate.

CST’s expanding structural polymer repair process is highly effective for preventing seepage and controlling erosion caused by water. Because of its hydro-insensitive characteristics, the ESP can be installed in wet environments and does not degrade in water. This in situ repair process saves irrigation districts and land owners the high cost and downtime of rip out and replace while providing a permanent solution.

Challenge

  • Create a permanent solution to undermining and channeling caused by water.
  • Fill voids without having to excavate the structure.
  • Consolidate the soil and rock material into an effective support system for the structure.

Benefits

  • ZERO EXCAVATION in situ repair process.
  • Hydro-Insensitive material.
  • Easily reach areas where large equipment would cause damage, or unable to access.
  • Effective rehabilitation of existing infrastructure eliminates cost of rip out and replace.
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City of Buffalo WY Swimming Pool Void Fill Soil Stabilization

Problem

The City of Buffalo Wyoming’s public pool had experienced large amounts of water loss due to leaks in the main fill lines beneath the pool. Cracks in the concrete floor of the pool had also contributed to the water loss.

The leaks were causing ponds of water to develop beneath the pool, weakening base soils and this massive structure’s support system.

The City needed a solution that would seal the leaks in the main lines and underseal the floor of the pool to stop water loss.

Because of the large size, tearing out the concrete to repair the leaks would be extremely expensive and would cause major disruption for the public with a lengthy closure.

The City was looking for an in situ repair that would seal the leaks, stabilize base soils and allow the pool to be returned to service quickly.

Solution

CST partnered with City of Buffalo Public Works Director Les Hook, and department staff to design an in situ repair to seal the leaks, stabilize and void fill the soils to support the pool.

Through a thorough investigation of the pool, it was determined that the ponding water was mainly collecting beneath the deeper end.

Injection holes were drilled, and the crew installed expanding structural polymer, starting at the shallow end, and working towards the deeper end of the pool.

The injection pattern was carefully designed to only void fill and underseal the bottom of the pool without lifting any of the concrete.

As injections were made, water was displaced and pushed out from beneath the pool and the saturated support soils.

Result

A total of 30,454 square feet area was successfully void filled and under sealed in a matter of a few days using CST’s expanding structural polymer injection technologies.

The repair did not require any excavation and the pool was immediately available to be refilled and put back into use following completion of CST’s polymer injection process.

The City saved thousands of dollars avoiding a rip out and replace scenario.

The hydro-insensitive characteristics of CST’s expanding structural polymer is ideal for rehabilitating leaking infrastructure. The Zero Excavation repair process is an ideal solution for repairing water lines, sewer connections, dams, inlets, irrigation structures, manholes and ground water cutoff walls. The high ten-sile strength of the material mitigates against channeling and is an ideal void fill and soil stabilization solution.

Challenges

  • Design a cost effective repair solution to void and seal beneath the pool without tearing out the massive con-crete floor.
  • Complete repairs efficiently without major disruption to the public or a lengthy closure.
  • Stay within the City’s maintenance budget.

    • Benefits

  • Zero Excavation, in situ repairs.
  • Highly effective soil stabilization, void fill, and undersealing process.
  • Hydro-insensitive material works well in saturated environments.
  • High tensile strength mitigates against erosion and channeling.
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    Carbon Fiber Structural Repair Exterior Block Wall

    Problem

    This concrete masonry building had experienced cracking damage at the corners and around window and door openings. The building was occupied by several different businesses, including a Montessori School, infant daycare, and retail storage area.

    Y2 Consultants of Jackson Wyoming conducted an assessment including an infrared scan of the building that revealed construction deficiencies. The structural assessment of the building noted that the cracks were due to differential loading and insufficient horizontal rebar at the corners to tie the perpendicular walls together.

    The differential loading and insufficient rebar had stressed the CMU to crack in these loca-tions. In order to allow safe occupancy of the building, it was determined that a retrofit of the deficient areas was necessary. Repairs would need to be coordinated with the businesses using the building, without a lot of disruption.

    Solution

    A Carbon fiber retrofit repair process to strengthen the walls at the cracked corner areas was determined to be a viable solution. CST’s carbon fiber repair system is comprised of high strength carbon reinforced fabric strips, applied over a clean and prepped surface, and adhered using a high strength epoxy. CST crews first prepped the surface using surface grinders to remove existing paint and get the surface profile required. A boom lift was used to help the crew safely reach areas above the awning. CST power washed the exterior of the building where the carbon fiber reinforcement would be applied. Moisture tests of the block surface were taken to ensure project specifications were met for the surface conditions necessary to achieve maximum adhesion properties of the material. Once dry, primer, then a tack coat, and then saturated carbon fiber was applied to the wall followed by a final grey UV exposure rated coating to protect the material.

    Result

    CST crews successfully reinforced deficient and cracked areas of this concrete block building in a matter of days.
    The carbon fiber retrofit allowed the owners to keep business running and provide additional support to extend the useful life of the building for many more years. Carbon Fiber repair options such as the method used on this concrete masonry building strengthen existing structures, and provide a higher safety factor.

    For many older structures, where reinforcement may not have been included during construction, carbon fiber retrofit helps to stabilize and reinforce areas of concern, bringing older buildings up to current code regulations and extending their useful service life.

    CHALLENGES

    • Perform the repair without disrupting tenants of this commercial building.
    • Prepping the surface to meet specification for maximum adhesion of the car-bon fiber material.
    • Accessing areas above the awning of this structure to prep surface and install carbon fiber material.

    BENEFITS

    • In situ, non-disruptive repair.
    • Increased safety factor through strengthening of existing structural deficiencies.
    • Meeting current code regulations, allowing older buildings to continue to be used.
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    Railroad Subgrade Soil Stabilization Lift, and Re-alignment

    A 70 foot section of railroad track near Green River, Wyoming had experienced ongoing settlement issues. During springtime, and high water events, the area required weekly re-compaction and leveling. The replaced ballast would continually sink into the wet subgrade soils.

    A factor that contributed to the problem, is that the area is located at a drainage point of the surrounding hillsides.

    Settlement of the subgrade soils was a continual problem for the railroad as well as the unsafe conditions for freight trains and their personnel travelling over this section of track.

    Keeping the track open and safe was a major concern for the Rail Company.

    CST partnered with Watco Rail representative Neal Ward to design an effective repair solution for the settled areas of track.

    An initial site survey was conducted on all areas of the settled rail. Areas for treatment were identified and a site specific injection design was created to lift the settled areas, and stabilize the subgrade soils beneath the track and ballast to mitigate against any future settlement.

    CST installed a high density structural polymer at pre-determined depths to treat weak soil and lift the settled track sections. Crews alternated between sections to allow train traffic to continue through the area.

    All sections of settled track and weak soil zones were stabilized.

    Injections made into the weak soil zones effectively pushed water away from the areas, and provided a protective barrier beneath the ballast, to stabilize and protect the area against future settlement.

    Railroad track was lifted, and realigned to provide a stable, safe passage of the company’s freight trains and personnel traveling across the tracks.

    All work was completed in a matter of 3 working shifts without major closure or disruption to trains traveling through.

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    Union Pacific Railroad Crossing Lift Realignment and Soil Stabilization

    A Union Pacific Railroad Crossing at the entrance of the Mountain Cement plant located in Laramie Wyoming, had experienced settlement of the precast panels beneath the track.

    A soft spot beneath the panels and the presence of water had exacerbated settlement and caused the crossing panels to become misaligned.
    Ed Hinker, Union Pacific Track Maintenance Manager, contacted CST to analyze and create a repair plan to provide in situ stabilization and realignment of the crossing.

    Due to the location of the crossing, it was imperative that repairs be made quickly, without a lot of disruption to both truck and train traffic utilizing the crossing.

    CST partnered with UP maintenance personnel and designed a site specific injection plan to stabilize the soft soils, lift, and realign the precast crossing panels, as well as beneath additional areas of track.

    A thorough site investigation was first conducted to identify areas and depths for repair.

    CST’s technicians placed injection probes into predetermined locations and depths, installing a high density, expanding structural polymer to stabilize the soft spots in the soil, and lift to realign the settled crossing panels.

    Additional areas of subgrade soil were also treated in adjacent track sections leading up to and away from the crossing.
    The railroad crossing precast panels were lifted, realigned, and stabilized in a matter of hours. The subgrade soils beneath the panels and areas of track were stabilized to mitigate against additional settlement.

    Repairs were made with zero excavation and very little disruption to vehicles accessing the cement plant, or trains utilizing this section of track.

    All areas were immediately available for use following the repair.

    CST’s soil stabilization and concrete lifting technologies are an efficient and effective way to provide long term, precision repairs without the added expense of lengthy downtime or costly tear out and replace alternatives.

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    Mine Shaft Head Frame Footer Foundation Stabilization

    The head frame support leg foundation on one of the Tronox Alkali Corporation mine shafts had experienced settlement. As a result, movement of the footings had caused the head frame and shaft bucket to shift from center. The issue was discovered as crews and equipment were being lowered and retrieved from the mine shaft.

    Tronox Mine Foreman Todd Jackson contacted John Eddins, P.E. with JFC Engineers and Surveyors to investigate the problem. The goal was to find a solution that would effectively align the shaft and mitigate the issue of potential future tilt or settlement.

    Stabilizing the foundation of the head frame support and correcting the tilt to safely allow mine crews to use the equipment to access the mine shaft was critical.

    JFC Engineers contacted CST to help deter-mine the best solution to stabilize and realign the structure.

    CST partnered with JFC Engineers and performed a thorough site investigation. It was determined that the back leg of the head frame foundation would be treated using the Uretek Technologies to stabilize, lift, and realign the structure.

    Dynamic Cone Penetrometer tests were performed to determine the condition of soils below the frame’s legs. The tests and analysis revealed that the soil would need to be treated at two depths to lift and to stabilize the soils to assure no future settlement would occur. Injections were made at two depths under the foundation and at the toe of the foundation to mitigate potential slide or settlement in the soils. The treatment was to obtain the target realignment of the structure and the foundation stabilization with minimal disruption to the structure or operations.

    Injection probes were placed through the asphalt and into the soils at depth. Injections were made while closely monitoring elevations for movement.

    The mine shaft footer foundation was stabilized and the shaft frame vertically realigned. Due to the surgical precision of the injection process, no additional stress to the structure or horizontal movement occurred during the lift. Voids were eliminated beneath the footings, ensuring a strong and stable base to support the heavy load.

    The project was completed with minimal disruption and without having to take the equipment off line during the repair. The equipment was immediately put back into use with all repairs done in only two shifts. Most importantly, stability was restored quickly and efficiently, extending the safe use-life of this industrial structure.

    “The project was well planned and executed. The back leg foundations were lifted to the established target elevations which brought the head frame structure to verti-cal plumb. The client expressed their ap-preciation and satisfaction with the results” -John Eddins, P.E., JFC Engineers & Surveyors

    CHALLENGES
    Stabilize the soil beneath this large piece of equipment without having to take the shaft offline or deconstruct the head frame.
    Correct the tilt of the head frame to bring the shaft bucket operation back to center.”

    BENEFITS
    In Situ, Fast, No-Dig Process
    Ability to Lift Heavy Loads with Surgical Precision
    Long Lasting Repair
    Extends Use Life of Existing Structures