Ready Mixed Concrete CLSM Jobs
Utility fill Projects
Controlled Low Strength Concrete. This is a product category that exists and is needed in every market , every day. D.O.T.’s often need to dig in roads/streets to repair or replace utilities. Ability to excavate and fill quickly, all with the idea that probable future excavation means the concrete fill needs to designed to be excavatable with a backhoe. So, obtaining a minimum strength quickly so that road topping can be applied at the earliest possible time, and yet not exceeding a maximum strength (often around 200psi) – is a real challenge for typical concrete approaches.
Typical concrete approaches allow for early strength, but because of various factors, particularly density of materials, the concrete will continue to gain strength, with psi in most cases far exceeding maximum specifications.
Without question, the best way to design this type of product is to use a “controlled density “ approach. This can allow for fast set up, allowing the job to be finished quickly, however by using a “controlled density” approach the density will determine or limit the strength ceiling/maximum.
In addition to predictable/controlled density – routinely done even up to 70% or 80% - Miracon’s® products really standout in the market because, in addition to the low density possibilities, it is easy to really optimize the speed of these types of jobs, because pouring to high lifts ( 2” to 15’)without any settling whatsoever makes this type of job go really fast.
When soil stabilization is needed prior to construction of structural buildings, the choice is typically to use compacted sand or to use CLSM. While it might seem easy to use compacted sand, this is typically a very time-intensive process as compared to choosing Miracon’s® ToughAir® or CapCell® technology to design this product/process. Using our product, completion of this phase of commercial projects is often completed in 25% to 30% of the time – as compared to using a compacted sand approach. As mentioned, our product is so stable that pouring lifts of 2” to 15’ high is often done , because there is typically no settling or shrinkage. Again, strength can easily be designed to achieve quick/next day drivable strength.
In a recent project, 18,000 cubic yards of CLSM were poured at 9’ to 12’ height requirements, “zero” shrinkage, drive-on capability at 18 hours – completing the job in 1/3 the time that a compacted soil approach would have taken.
Another example of how fast and predictable a CLSM mix with Miracon’s® product can be – a small job: about 10 t/L’s (100 cubic yards) with the air entrainment of the mix design spec’d at 72% ±3%. Further the mix had to be pumped from the ground and up 10 stories. Densities were taken at the chute of the truck, before placement into the pump bucket. Then densities were taken 10 stories up, at point of placement. The placement densities were all within spec., and deviation of ToughAir® entrainment readings from ground level to readings at 10 stories high were never more than 1.5%.
Speed of placement with CLSM projects can often be enhanced by multiple trucks unloading at one time, or pumping, or a combination of both. Also, since these mixes typically have great flow properties as well as self-level upon placement, there is often no manpower required at point of placement. One pour/one placement and done. Much faster than compacted soil/sand.
Other – Mining, Sound Insulation, Non-Structural Seismic Applications, And Many More
There is a very broad range of applications for which CLSM is the ideal product to make and use. In mining, CLSM is often used for non-load bearing supports and provides a visible indication of the soundness of the tunnel which is only being used for a short time frame.
Since a low density product made with ToughAir®or CapCell® has a closed cell structure to the matrix, it is an ideal product in wall systems where sound reduction is desired.
One very unique, but telling application was when 4,000 cubic yards of CLSM were used to build the new docking station walls – in 28 feet of sea water – for nuclear subs, at Pearl Harbor. The seismic properties of the CLSM allowed for these massive vessels to dock/tie up without damage to the vessel or the wall.