FAST IMPROVEMENT OF GEOTECHNICAL PROPERTIES
FIRST THINGS FIRST
Soil treatment is a fast, cost-efficient and lasting intervention carried out in the phase of earthworks, and serves to ensure the long-term compliance with all expectations. Soil improvement entails the enhancement of soil properties by adding the suitable binders to the original soil or the material brought in from borrow pits – this way, the earthworks will become capable of complying with the relevant regulations. The procedure has a favourable effect on the load bearing of the installed layers, thus further works can be kicked off sooner. Meanwhile, the mechanical properties of the stabilised layer, as well as its resistance to frost and water ingress will be significantly improved in the long run.
AS EARLY AS THE DESIGN PHASE
The procedure is ideal for the construction or expansion of parking lots, industrial and commercial facilities, logistics hubs, roads and motorways. As the most expedient solution, stabilisation should be planned simultaneously with the preparation of the soil mechanical report – therefore, the results can be considered straight away when sizing the given industrial floor or the pavement structure. This can lead to a substantial reduction in the costs of the investment.
Quite often, the need for soil treatment arises only during the installation of earthworks due to adverse weather conditions or unforeseen changes in the moisture content or other properties of the soil. In such cases, fast and cost-efficient in-situ soil improvement remains the only reasonable option.
SOIL TREATMENT TECHNOLOGIES
To immediately improve geotechnical properties, lime products are mixed into the soil. The main purpose of the procedure is to dry out the soil and to reduce its plasticity, which enhances installability, makes it easier to ensure the necessary compaction, and boosts the load bearing of the soil – even in case of materials unsuitable for earthworks. The treatment facilitates the spreading, mixing and compaction of the soil, as well as moving around on top of the earthworks, which allows for the subsequent construction phases to be commenced sooner. The intervention induces chemical changes, which alters certain components of the soil, as well as its structure. As a consequence, a lasting improvement of shear strength and load bearing is achieved, while a long-term resistance to frost and water ingress is also formed.
By adding cement to the soil, we create a mixture suitable for stabilising, reinforcing and improving the soil. As a key factor, the job site should be accessible during earthworks, and construction progress should be as fast as possible – to this end, the required load bearing should be reached as soon as possible. In case of certain fine-grained soils, lime pre-treatment opens the way for the subsequent stabilisation with cement.
A SURE THING
As part of soil improvement processes, it is customary to verify the quantity of binders and the required depth of the intervention through the installation of a trial section. Within the trial section, it is highly recommended to create sub-sections using different binder content and/or layer thickness options. The final technical solution should be picked following the load bearing and compaction tests carried out on these different sub-sections.