Settlement is often attributable to inadequate fill material such as frozen fill or improper base compaction. Other causes contributing to a weak base soils condition also include: drying out of the ground surface layers (desiccation); reduction in water table level; wash-out caused by leaking water pipes, sewers and drains; excavations adjacent to buildings; inadequate foundation design; vibrations caused by heavy road traffic or adjacent construction sites; and base soils with different geological strata.
Whatever the cause for subsidence in the building floor slab or foundation, the base soils will require densification to enhance their load-bearing capacity to bear the loading of the building structure.
Poly-Mor strongly advises that a third party engineering firm be involved to undertake and provide the appropriate soils testing and analysis of the “Before” and “After” SPT’s. In most cases Poly-Mor would recommend that a field test firstly be undertaken prior to any large scale treatment being undertaken
Before occupying or introducing equipment to an area, it is important to take into consideration the strength of the soil underneath. Poly-Mor Canada Inc. uses a two-part polymer material injected through injection probes drilled in the base soils. The resulting mixture polymerizes and expands within the base soils. With this expansion, the material aggressively seeks out voids filling them while densifying surrounding soils and increasing the bearing capacity of the base soils significantly. This unique process relies on the expansive properties of a two-part expanding resin system, with an expansion co-efficient of thirty to one, and a quick 15 minute cure time.
Poly-Mor also is capable of multi-layered injection process. Resin is filled at varying depths to fill all voids and densify the soil. Typically the load bearing capacity can be more than doubled and will be sufficient to load over and above the desired requirements.
Poly-Mor uses a form of “chemical compaction grouting” where a special high density, hydro-insensitive expanding polymer resin is used to fill, densify and stabilize low density, compressible soils to depths of 30 feet and beyond. The Poly-Mor resins are delivered and placed at the appropriate depths in the required soils strata via drilled or driven injection probes . As the Poly-Mor resin is injected, it expands and provides a compaction or lift force of up to 50 tons per square meter thereby filling, compressing and compacting adjacent soils and significantly increasing the load bearing capacity of the base soils resting under a structure. Our soils densification process is also excellent for conglomerating and binding non-cohesive soils.
We are able to “fix dirt”!!! If you are challenged by a poorly compacted sub- grade, or a weak base soils strata at depth, or require agglomeration of base soils such as blast rock, etc., Poly-Mor technology will resolve your challenge! Do you have such a challenge?
The response of culverts or tunnels to static loads is controlled by soil arching and the imperative need to ensure the relative stiffness between the culvert and surrounding soil is maintained. Failure of corrugated pipes and even concrete pipes with applied external loads is typically by unconstrained buckling of the pipe. Placement of a structural fill that is continuous and contiguous around the pipe, significantly enhances the pipe strength and minimizes / eliminates buckling possibility. The use of expanding polymer grouting systems is significantly more effective then using cementitious grouts.
The parameters of this treatment technique make it suited to a large range of cohesive soils including a wide range of clays up to 44% plasticity index. We are unable to treat clays, silts or other fine soils with large volumetric changes where thrust from the clay exceeds the dead load of the building or foundation weight or where the soils are so heavily compacted that our resins cannot permeate same. Also, in very weak alluvial soils such as peat, hog fuel, saturated silts and other weak sediments direct injection into same will densify the weak soils but an inordinate amount of expanding resin would be required and thus make the process uneconomical. Further, and in all cases, injection at depth is done blindly and there is no telling exactly where the expanding resin is traveling to. Before and After Standard Penetration Tests (SPT) are the only way to determine if the base soils have been densified sufficiently to accomplish the desired load bearing requirements.
Recently POLY-MOR Canada Inc. was contracted to inject our amazing polymer resins below a slab on grade floor area in one of Toronto’s oldest hospitals.
The Issue: An area of the hospital was being renovated with pluming services being reallocated. When the floor was saw cut large voids were found below the slab on grade as well as weak soils down to 3m depths.
The Solution: After close examination of the soil investigations, discussions were carried out with the project consultants and the hospital administrators as to the best course of action. POLY-MOR proposed a series of injections to target weak soils throughout the work space as well as void filling the remaining slab on grade floor to support it fully.
POLY-MOR Canada worked closely with the GC on site, the owners and the consultants to propose and develop a methodology. The knowledge and
experience POLY-MOR Canada provides allowed for a scope of work that would avoid the normal need to excavate and replace a massive amount of backfill that was in place. This saved an enormous amount of time as well as costs for the hospital administrators. This project was completed in ten days, drastically reducing the impact on overall project timeline. Our unique polymer resins are incredibly effective in filling voids, annular spaces in weak back fill and increasing soil strength as they expand as they are injected. Don’t be fooled by other companies stating they do the same work as POLY-MOR and use the same materials. That is simply not true. POLY-MOR Canada Inc. leads the way in the Canadian market with the most experience and knowledge and hands down the best materials available to get the job done.
Water Treatment Plant, South Western Ont.
Concrete floor slabs within a water treatment plant located in Kent County had started to settle as much as 2”. Upon further investigation, it became known that the subgrade problem was deeper then originally anticipated. Boreholes showed very low soil density values all the way to the 15’ level and the subgrade was also very saturated. Traditional repairs would have involved excavation of the entire site and repouring of new slabs. This was not feasible due to the fact there could be no shut down time in the treatment plant and the cost was extremely high. The POLY-MOR Method was chosen for a number of reasons such as the 10 yr warranty against any shrinkage or deterioration, virtually no disruption, no added overburden to the already suspect base soils and a project cost that was a fraction of any alternative. One of the main reasons was that POLY-MOR Canada also has a “hydro-insensitive” resin, which can be injected into highly saturated sub grades and still obtain the same strengths and characteristics as our regular resins which are injected into dry sub grades.
A local engineering firm working along side with POLY-MOR Canada designed a column and arch system to stabilize the suspect subgrade. POLY-MOR Canada was to inject at the 12’, 9’, 6’ & 3’ locations, in effect creating a series of piles. In between these piles POLY-MOR injected the polymer resins, which expand to aggressively void fill and stabilize the weak base soils at the 3’ level. This shallow injection would become the center of the arch. This system was done throughout the plant successfully.
POLY-MOR Canada was able to stabilize an area of approximately 3,200 sq.ft. in seven days work. This included not only stabilizing the subgrade, but also lifting the settled floor slabs to original elevation. The result is a complete void fill and stabilization of the base soils ensuring a solid base for the slabs and loads placed on them. All parties were very pleased with the work done, the short length of time it took to successfully complete the project and the cost savings that resulted from using the POLY-MOR Method.
DEEP STORM LINE STABILIZATION
major General Contractor was engaged by Alberta’s largest utility provider to stabilize the exterior perimeter of some 350m of deep storm water corrugated culvert running under the McKinnon Ravine in Edmonton to void-fill and enhance the pipe resistance to buckling from void conditions on the exterior of the pipe. During the initial construction of the storm line the voids were filled with shot-crete but either the voids were not completely filled during construction or the material deteriorated over time with significant sliding the result.
Poly-Mor crew accessed the deep storm line via catch basins and ran some 500 feet into the storm line and through 5/8″ holes drilled into the pipe on a 6′ staggered grid injected Poly-Mor 486 expanding resin system fully filling the voided areas. The client were particularly impressed when they saw how effectively the resin spread, as they were able to see the condensation on the pipe actually evaporate as the exothermic resin expanded. The test was a total success as evidenced by provision of another similar contract.