In unstable soils where temporary casing is required, self-drilling hollow bar system is a preferred alternative to coarse threaded solid bars.

Hollow bar offers fast, easy and flexible system in any soil conditions, which simultaneously acts as the drilling rod (with lost drill bit), grouting tube and reinforcement bar (tendon). In unstable soils, additional operations of inserting and extracting the casings are avoided. Self-drilling hollow bar system also eliminates the need for multi-stage grouting.

Hollow bar micropiles transfer tension, compression and alternating loads into the ground through skin friction, all in accordance to EN 14199.

Self-Drilling Hollow Bar Types

• R25 to R114, R-type threads
• T30 to T135, T-type threads

Corrosion Protection Systems

Self-Drilling Hollow Bar Micropiles can be supplied with

• Hot Dip Galvanizing to EN ISO 1461
• Duplex coating – Consists of a primary coating of hot dip galvanizing followed by a layer of epoxy powder coating