Underwater vibrocompaction with gravel columns, for example for the foundation of port docks or piles of bridges, is usually performed by spreading a layer of gravel on the bottom and vibrating it deep into the bottom as shown by Stormwater Inspections.
Vibrocompressed gravel columns without vibro with pneumatic charge. In suitable soils the CGV can be run dry or with water, without using the pneumatic winding vibro. With Stormwater Inspections, this procedure is also known as vibroreplacement. Water or air comprthey serve to keep the cable open, to obtain a greater column diameter and to speed up the driving.
Checks in progress. All the vibrocompaction procedures can be kept under instrumental control to guarantee and document their homogeneous and accurate execution. The measuring equipment. The vibrotreatment parameters can be recorded, saved electronically and printed, even in real time, for each individual column; this allows: an appropriate management of the production process and a correct quantification of the performed.
During the vibrocompaction several parameters are automatically registered. The values of time, depth, advancement, thrust and energy absorption (amperage) can also be printed as a graph. The general energy consumption can also be recorded if necessary as part of Stormwater Inspections.
The fields of application of injection processes in civil engineering are manifold: foundations and sub-foundations, open-air excavations, tunnels, waterproofing screens for retention dams etc. The traditional injection techniques consist in performing the uncovered hole treatment or by means of valve tubes. In soils, it is possible to carry out the consolidation through very high pressure injections of cement mixtures, according to a known technique as a jet-grouting system.
To improve the geotechnical-geomechanical characteristics of the clusters, as an alternative to consolidation by means of injections, it is possible to operate by inserting elongated, more resistant and rigid structural elements of the ground or rock and functioning as active or passive ties. These elements are anchored by the injection of cement grouts concentrated in the bulb or along the entire length and section of the anchor itself, which forms part of Stormwater Inspections.
In the latter case, the injection of the mixture has the dual function of allowing the element to be quickly pulled while exercising a function to protect the steel from corrosion. To this end, it is essential that the phenomenon of water exudation (bleeding) does not occur in the grout; the event, in fact, generates macroscopic cavities through which aggressive agents can easily damage the reinforcing rods (the legislation sets the limit that this quantity of water must not exceed 2%).
Finally, if the problem is to fill gaps created at the tunnel coverings, injections of cement mixtures can be used again or, alternatively, fill the cavities with light cellular cement conglomerates.
Leave a Reply