If groundwater or soil is contaminated, the environmental impact could be disastrous. Luckily, there are things that can be done in order to make sure any affected soil or groundwater does not create a true environmental hazard. Slurry trenching and creating a good slurry wall is precisely one such thing.
How Slurry Trenching and Slurry Wall Construction Works
If there is contaminated soil, contractors should first engage in slurry trenching before building the slurry wall. Slurry wall construction is a mixture of cement, bentonite and water. Once the slurry has been trenched down to the bedrock, a pre-cut keyway is created. The keyway cuts straight into the bedrock, where it creates a locking bond between the bedrocks it is on and the wall itself. Furthermore, it stops the contaminated or controlled area from seeping. It can be incredibly expensive to remediate contaminated areas or soil. Additionally, it takes a great deal of time. This is why slurry walls are such a good option, because they are both affordable and viable.
The Role of Composite Mixes
Sometimes, depending on what the wall itself needs, it is possible to combine environmentally friendly polymers to the mixture. This is to help the chemical, filtering or strength resistivity factors, which usually are not present in a typical, standard mix. When a contractor does decide to make a variation, the mix is known as a “composite mix”. The mix has to be created with different materials and the goal of the mixture will determine which materials are needed. Civil or environmental engineers will need to research the soil conditions and other needs in order to decide which mixture will be able to deliver the desired results.
Stabilising Backfill and Soil
Slurry walls are beneficial for other things as well, including the stabilisation of soil. It is possible to create a slurry trench, which can create below grade slurry walls. The goal of this is to stabilise a substructure by preventing erosion. Furthermore, it moves the water away from the structure itself. It is also possible to mix the construction materials of a slurry wall with backfill materials. This creates a very firm product that does not move in the same way as regular soil. Furthermore, it stops groundwater from being able to get into the foundations and causing damage.
Stabilization of Excavation
Finally, it is possible to use a slurry mixture in order to stabilise the trench excavations themselves This is a form of trench shoring. Here, slurry remains within the trench itself all the time. It is then excavated through, before reinforcement bars are placed and lowered inside the trench itself. Once the trench is fully completed, the concrete mixture is ready to be pumped in. All that needs doing first is displacing the slurry itself, which is a very easy task. This is not a common type of excavation, but it can be required in such areas with very limited site access. Other times, we see this in areas that must remain undisturbed, either due to environmental or constructional concerns.