Type of instability
It is a building in which the differential failure of AngolatA determined significant Cracks at 45 ° in the supporting walls. The structure we are talking about today is totally built masonryconsisting of 2 floors above ground, without reinforced concrete foundations. Although the loads are not high, a significant one loss of water upstreamcoming from the public sewage network, led to a very important instabilityaffecting the safety of the house.
The water, over the course of several years, has in fact regretted the land and the finest fraction was issued, causing a progressive transfer of the foundations and the consequent unusability of the building. The transfer of the foundations forced the owners to intervene with the realization of deep foundations to stop the failure and proceed with the necessary restorations.
Consolidation foundations with micropals at the neary
The client’s technicians took into consideration all the possible consolidation techniques of the foundations, but immediately opting for the deep foundations. In fact in precarious situations such as the one described The micropals represent Certainly The most suitable and definitive solution over time. Among the methodologies examined, the engineer Balducci has oriented himself on Systab preloaded poles.
The intervention took place according to the following operational phases:
- excavation for the construction of the new curb in Ca connected to the existing walls;
- put in place of the shirt pipes inside the curb itself;
- jet of the new reinforced concrete curb;
- waiting for the jet maturation (about 4 weeks);
- inflammation of micropals with continuous monitoring of the installation pressures, until the project courses/depths are achieved;
- load tests according to legislation for the testing of the micropalification;
- preload of each micropal with pressure higher than those of exercise and lifting (if the structure makes it possible and needs it, as in this case);
- Final fixing of the micropal to the top collar of the shirt tubes;
- I refer and consequent restoration of external flooring.
Advantages of background consolidation with preloaded poles
The consolidation of the foundations with preloaded micropals allowed to definitively stabilize the corner of the house Riduing the necessary safety and allowing the restoration of the cracks in the walls. The active technique in this case also allowed reduce the extent of the cracks.
In addition, this technique has many advantages, which characterize it with respect to traditional techniques:
- Compared to the classic methodologies it allows Very quick execution times;
- does not produce resulting material of any kind;
- they are not normally used mud or water (dry construction sitealso suitable in narrow and internal environments);
- No dangerous vibration for superstructures;
- there flow rate of each single pole is tested in the course of work;
- preload for the cancellation of primary sagging for all poles;
- Possibility of lifting and recovery of planarity If the structure allows it and needs it.
The complete work, as regards the phase of the inflammation of the foundation poles, lasted 2 days and allowed the inflammation of 5 micropals of diameter 114 mm and average length of 6 meterswith definitive fixing of the poles to the shirt tubes.
The technology used has allowed us to operate quickly, with minimal inconveniences and without producing harmful stresses for the structure inhabited, but indeed recovering part of the failure and reducing the extent of the cracks on the walls.
For more information on technology
Systab.it
The author of the article, Cristian Setti, graduated in 1999 in Geological Sciences from the University of Ferrara. For 15 years he has been commercial director at primary construction company operating in the consolidation of the foundations, and since 2015 he has been a partner and commercial director of Systab srl, a company specialized in the consolidation of land and foundations with low invasive techniques.
