Vibro replacement
Subsoil improvement using compacted columns of gravel or crushed stone

The vibro-compaction method is used for subsoil improvement in soils with low bearing capacity. This involves creating compacted columns of mineral materials, such as gravel or crushed stone, within the subsoil. The work is carried out on a project-by-project basis, taking into account the geotechnical and structural requirements.

Encyclopedia: Vibro replacement

Deep vibro compaction
Subsoil improvement in accordance with DIN EN 14731

Vibro replacement is a type of deep vibratory compaction method and is used for subsoil improvement. It involves creating columns of gravel or crushed stone to adapt the properties of the subsoil to the requirements of the construction project. The method is used in particular in fine-grained and mixed-grained soils.

Characteristics of the method

In construction projects involving soil layers with low bearing capacity, subsoil improvement measures may be considered as an alternative to other foundation or ground treatment measures. The selection of the appropriate method is made taking into account the geological, technical and project-specific conditions.

Vibro replacement is carried out using mineral materials such as gravel or crushed stone. Depending on the project requirements, different column diameters, column spacings and embedment depths are used.

Technical brochure
Vibratory compaction

Technische Broschuere Baugrundverbesserung

Broschüre: Baugrundverbesserung

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Applications

The deep vibrocompaction method is a cost-effective means of subsoil improvement and is mainly used for the foundations of structures on soil that lacks sufficient bearing capacity. These include:

Residential and commercial buildings
Hotel buildings
Industrial buildings
Office and administrative buildings
Shopping centres

Vibro replacement is used in fine-grained and mixed-grained soils. In this process, columns of gravel or crushed stone are progressively formed in soils that are difficult or impossible to compact (preferably washed gravel with a grain size of 8/16 mm or 8/32 mm).

Benefits / Features

Vibro replacement can be adapted to different subsoil conditions and project requirements through various implementation options.

Soil management: Complete soil displacement without conventional soil excavation.
Materials used: Construction of the rammed columns using mineral materials such as gravel or crushed stone.
Implementation: Adjustment of the insertion depth in accordance with subsoil conditions or project-specific requirements.
Method variants: In very soft soils, the columns can be grouted by adding a suspension.
Column arrangement: Different column diameters, column spacings and grid patterns are possible.
Subsoil properties: Depending on the specific application, the bearing capacity and water permeability of the subsoil can be influenced.

Quality assurance: Implementation in accordance with defined quality and monitoring measures.

Basic facts

Standards and regulations

Soil improvement by means of deep vibration is designed and produced in accordance with the German national standard DIN EN 14 731.

Production

The vibratory tamper is aligned above the point where the column is to be produced and the gravel/material bucket is loaded by a telescopic forklift or wheel loader. The vibrator is then lowered to the target depth with the aid of a hydraulic excavator or a caterpillar. The soil is compacted in stages from the planned target depth upwards.

Pressurised air is used to feed backfill material into any cavities that occur. The vibrator is then lowered back into the ground to compact the backfill and the surrounding soil.

Once compaction is complete, the ground surface is levelled and compacted with a surface vibrator.

Quality assurance

The following measures, in particular, contribute to a high standard of workmanship:

Individually coordinated procedural instructions
Compliance with the requirements of the DIN EN 14 731 standard
Monitoring of automatic production logs
Digital monitoring and analysis of production parameters
Clear processes via our quality management system in accordance with DIN EN ISO 9001:2015

Design variants

Depending on the subsoil conditions, load requirements and project specifications, various subsoil improvement methods are employed.

Vibratory compaction

Vibratory compaction is used for coarse-grained soils. In this process, the soil is compacted by driving a deep vibrator into the ground.

Vibro replacement

Vibro replacement is used in fine-grained and mixed-grained soils. In this method, columns of gravel or crushed stone are driven into the subsoil. The areas of application for vibro replacement and vibro-compaction are shown in the grain size diagram below.

In-situ concrete vibro-columns

In-situ concrete vibro-columns are used in projects with high load requirements. The choice of method is made taking into account the geotechnical and project-specific constraints.