Pile drilling and pre-drilling

Even in the most difficult-to-reach places, Van Schie knows how to pre-drill correctly. Inner-city without vibrations or conversely in wetlands with floatable instruments; the trickier, the more fun it becomes for the drilling experts. Every pile type, location and soil type can be worked with the right method, experience and choice of equipment.

With pre-drilling, hard ground layers are more easily penetrated. It releases less to virtually no vibration, offering tremendous benefits for environments. Moreover, you can get much deeper with pre-drilling. Up to 22 meters! Even with a compact drilling rig that can actually go anywhere. Incidentally, Van Schie has facilities that allow it to drill into contaminated soil.

Van Schie’s drilling technology has 3 remarkable methods, screw injection piles, mixed-in-place and soil mix.

Screw injection piles

The Schie screw injection pile (SIP) is a highly advanced and efficient foundation method, particularly suitable for vibration-prone sites. The Schie SIP method assumes a tubular steel pile with screw blades, which is encased and filled with cement grout. The screw injection piles are screwed into the ground, are vibration-free and soil displacing.

To reduce resistance and achieve an extra rigid result, cement grout is injected simultaneously during screwing. In addition, the grout column guarantees the support base of the screw blade. This also gives the pole a high load-bearing capacity. The steel core gives the posts excellent absorbable tensile strength. Screw injection piles are ideally suited within urban redevelopment, in vibration-prone locations, as recessed piles for basements and as a low-vibration, soil displacement system for soil contamination.

Mixed-in-place

In the Netherlands, Mixed-In-Place is still relatively unknown, but in England and Germany it is already a great success. This variant of soilmix focuses on infill development, that is, building in locations within built-up areas.

Method of operation MIP

Mixed-In-Place, or MIP for short, is applied with a drilling crane. During drilling, cement is injected along through the inside of the drill bit, creating a concrete column in the ground. Arranged together, these columns then form a perfect wall.

Benefits of a MIP wall

The installation of a MIP wall is done vibration-free, so there is less risk of damage to surrounding buildings. In addition, there is also less chance of sagging and it is easier to get into all corners. The wall can also be used as a final exterior wall. This can save a basement wall. A MIP wall can also be used as a seepage screen. A seepage screen is an artificial measure to hold back seepage water.

Soilmix

Inner-city construction is one of Van Schie’s focal points. By applying new techniques and machinery, soil contamination is being controlled more and more efficiently. Soilmix is one such new technique.

Through a combination of drilling technology and insitu remediation according to the BRL 7002, soilmix allows remediation at great depths without having to excavate the entire site. Sheet piling, which can also sometimes cause problems indoors because of vibrations, can also be omitted when soilmix is applied.

The Soilmix Technique

The process of soilmix is very complex. Basically, the drill acts like a bar mixer. During drilling, iron sulfide is injected into the soil along with it. The iron sulfides cause chlorine compounds to break down and be converted to substances that do naturally occur in the soil, such as salt and alkanes. The soil to iron sulfide ratio is determined in advance in laboratories.

The drilling crane used for this type of project was developed by Van Schie himself. The installation consists of a double drill. GPS coordinates are used to position the borehole.