Land consolidation method –

Land consolidation: how to safeguard safety in buildings to avoid structural failures

The building safety it depends on multiple factors, for each of which the manifestations over time must be carefully evaluated, in order to avoid the possibility of compromising in some way the safety of those who live there.

The solution of consolidating the foundation soil with injections of Uretek resins

Among the most important causes, detrimental to the safety of a building, i static failures they represent a relevant category responsible in many cases of real disasters, resulting in victims and damage to real estate.

Foundation soil failure: how does it manifest itself?

The manifestation of a failure can appear at any time and can have a gradual onsetmany times not evident enough to the eyes of a normal observer, or in the most striking cases manifest itself with sudden collapses the reasons for which at first glance cannot be explained. THE responsible factors of these manifestations are different, among these the main one is the foundation ground on which the building rests.

Il bottom plane, or foundation soilon which the building rests, may undergo variations in its load-bearing capacity, following water infiltrations, adjacent excavations, demolitions of bordering seabed works, landslides, seismic events, presence of underground tanks, removal of elements consolidators, etc. Another possible cause of sagging is desiccation of the foundation soil, with relative decrease in volume, due to prolonged dry periods or, on the contrary, to extreme climatic phenomena, such as floods.

Continuous laser monitoring during Uretek surgery

Added to these phenomena are all the factors external to the installation surface which are in some way related to the load-bearing capacity of the building structure, as being responsible for further failures; among these, we can list:

1. i excessive overloadssee reckless superelevations;
2. the changes to structural diagram of the building resulting from movements of rooms, cuts of beams and pillars;
3. introduction of innovative structural elements not suited to the type of existing structure;
4. excessive and repeated shaking actions;
5. execution of construction works not in perfect working order

In addition to the above, we must not forget the slow and inexorable action of structural degradation, caused by lack of maintenance, the presence of aggressive agents, etc.

In consideration of what has been said, it is necessary to take into account how the appearance of a injury while announcing the onset of a more or less serious static instability, it does not highlight with equal immediacy the causes that produced it.

Consolidation of foundations and foundation soils: how to act

For the above reason, it is indispensable avoid interpreting according to one’s impression such phenomena, with the risk of adopting measures that are not adequate for the case or even more harmful than the disruption itself.

Many props actions without criteria have caused more damage than the collapse itself. In the presence of a lesion on a wall, it is possible to carry out an initial check of the severity of the instability in order to identify whether or not it is necessary to entrust the examination of the state of the premises to specialized personnel.

Crack detection and failure monitoring – Uretek

The first rule to follow, to examine the severity of this evidence consists in exposing the lesion itself, which can be achieved by removing part of the plaster to the right and left of the lesion limited to the central part of the same and near the two ends.

This operation can highlight, for example in wall structures, a simple breakage of the plaster or a fracture of the underlying masonry ashlar which highlights the need to act in a more specific and professional manner in identifying the causes of the failure.

Land subsidence? Cracks in the walls? What are the possible causes

Some types of these lesions can highlight phenomena that have nothing to do with static instability, think of the presence of hidden flues or wooden beams hidden by repeated stratifications of plaster carried out at different times, etc.

From the above, it is clear that it is fundamental for safety and the application of the right type of remedy, know the causes which caused the failure and only after having identified them, choose the type of intervention most suited to the case.

Drilling operation preparatory to the injection of Uretek resin

To make the less expert reader better understand how to proceed, it is enough to draw a parallel between the health of the building and that of the human being: a headache can be generated by multiple causes, for which palliative care is of little use and in many cases can be even more harmful than the event itself.

Even after ascertaining the cause responsible for the ongoing disruption, the choice of the type of intervention must be the subject of a careful analysis of the relevant factors of each specific situation; the same land subsidence technically defined as seabed subsidence, or subsidence of the foundation soilcan be solved using different consolidation methodswhich vary depending on the type of structure, the characteristics of the site and many other components, in addition to those of an economic nature.

Consolidation of the foundation soil, the advantages of intervention with resin injections

The method of consolidating the foundation soil with resin injections is characterized by its minimal invasiveness and the ability to solve the problem definitively.

In the case of monumental and historic buildings, for example, the intervention of consolidating the foundation soil with resin injections proves to be the most suitable, since, compared to classic consolidation interventions, it does not require excavations and demolitions. Another characterizing factor of solutions with resin injections is the speed of intervention.

Insertion of injection cannulae for consolidation of the foundation soil

Open excavation interventions in the winter periods or in the presence of sudden rain, they become difficult and in some ways even harmful to the safety of the building.
Furthermore, it should not be forgotten that these traditional interventions involve both the demolition of the internal and external paving layer and, once consolidation operations have taken place, the repositioning of the removed paving.

Now, in the presence of floorings easily available, their restoration does not involve particular problems, but when dealing with floors made up of aggregations of different materials, which in some situations represent strongly characterizing representations of the site, their restoration involves a considerable difficulty.

For those like myself who have found themselves intervening in many historic centresespecially on the occasion of the seismic events of 23 November 1980, the memory of such operations in relation to modern intervention methods makes us reflect on the great progress achieved by today’s methods.

In fact, being able to have a modern and non-invasive method like the one provided by Ureteksignificantly reduces working time, in fact current interventions can be carried out in half the time compared to traditional methods.

Raising an old floor, filling a cavity, making the structures more suitable to withstand seismic action, using expanding polyurethane resins to consolidate the ground, making it at the same time more stable over time, thus avoiding any subsidence, represents the great alternative offered by Uretek.

Foundation soil consolidation with Deep Injections technology

Uretek Deep Injections technology, designed and patented by Uretek Italia Spaallows the soil to be consolidated and stabilized quickly and definitively, solving the problem of differential settlements in depth.

Uretek resin injections

With Deep Injections technology, Uretek solves every problem of subsidence of the underlying ground, with ad hoc designed solutions both for private homes, condominiums and industrial buildings and for buildings of historical-artistic value, as demonstrated by its application in an important context such as that of Punta della Dogana Palace in Venice.

Deep Injections is the only patented method with expanding resins that can include 20 years of applications and over 100,000 interventions carried out around the world, of which more than 20,000 in Italy alone.

The injections are made at three or more depth levels to resolve any critical issues quickly and lastingly with an innovative system that exploits the peculiar characteristics of the patented resin Geoplus^® (eco-friendly and tested in the laboratories of the University of Padua).

The Uretek method: safe results in three simple steps

1) Free visit and inspectionby a specialized technician with analysis of the crack pattern and the type of soil. The geotechnical characteristics are identified and the type of intervention to be carried out is established using, where necessary, dedicated calculation software.

2) During theintervention normal activity within the building is not interrupted.
The works begin with the construction of microperforations with a diameter of 26 mm, along the load-bearing walls and through the foundation, to reach the soil to be treated.

3) Subsequently, pins are inserted into the holes steel tubes to allow the injection of the resin which expands and immediately consolidates the soil.
Geoplus, capable of lifting a building by even tens of cm, passes from the liquid to the solid state in a few moments, expanding in every direction and exerting a pressure of up to 100 kg/cm on the surrounding ground².

Ground consolidation with Uretek expanding resins

At the end of the operation, quickly and safely thanks to a constant laser monitoringthe problem is solved quickly and definitively.
The technology Deep Injections di Uretek enjoys a double guarantee: 10 years from the completion date of the works guaranteed yes Uretek and 10 years from the guaranteed completion date from QBE insurance policy leading international company.

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THE EDITORIAL TEAM RECOMMENDS

The company, founded in 1990, has always dealt with foundation and soil consolidation using injections of expanding resin. Since the first years of activity it has constantly invested in human resources in the field of applied research in the field of consolidations.

The result of a company policy aimed at continuous improvement is the development of new technologiesobtaining international patents, collaboration with prestigious international universities and quality certifications.