DYWI® Drill Hollow Bar
DYWIDAG’s Hollow Bar Micropile system combines drilling, grouting, and reinforcement in one solution. Ideal for limited-access sites, unstable ground, and aggressive schedules. From tunnelling, to bridge retrofits, our Hollow Bar Micropiles are engineered for speed, stability, and strength - even in the most complex geotechnical environments.
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Fast to install and high-performing
DYWIDAG’s DYWI® Drill Hollow Bar Micropile combines drilling, pressure‑grouting, and reinforcement in a single efficient operation, making it ideal for restricted-access sites, tight urban environments, unstable ground, or for projects where speed is critical.
This self-drilling micropile system is designed to support structures by transferring loads to deeper, more stable soil or rock. Whether you're underpinning an existing foundation, constructing a bridge abutment, or building in urban environments, DYWI® Drill provides reliable, high-capacity load transfer without the need for casing or pre-drilling.
Key features
Single pass installation
DYWI® Drill micropiles are installed using a single operation that combines drilling, grouting, and reinforcement. This reduces equipment needs, speeds up timelines, and eliminates the need for casing — even in collapsing ground conditions.
Performs in poor ground conditions
From loose fill to collapsing soils, the self-drilling design enables fast penetration and immediate support. The sacrificial drill bit and pressure-grouted bar ensure a strong bond where conventional piles can’t be used.
Ideal for restricted access sites
With compact rig compatibility, modular bar lengths, and a lightweight design, the system can be installed in basements, tunnels, urban infill locations, or beneath existing structures — wherever space is limited or headroom is tight.
High load-bearing capacity
Designed for tension, compression, and combined loading, the system can handle substantial structural demands. It's suitable for new construction or retrofitting foundations that require reliable deep-ground load transfer.
Manufactured to the highest standards
The DYWI® Drill hollow bar is a fully threaded, self-drilling solution for applications in civil engineering, including soil nailing, slope stabilization, micropiles, and rock anchoring. The design allows simultaneous drilling and grouting, eliminating the need for casing in weak or brittle soils - streamlining installation while meeting industry safety and quality standards.
Manufactured to the highest standards and compliant with regulations across the globe, DYWI® Drill Hollow Bar ensures reliable performance in critical geotechnical projects. The DYWI® Drill Hollow Bar is rigorously tested to ensure consistent performance in critical geotechnical applications. Its use supports compliance with project-specific specifications, environmental considerations, and relevant local codes.
Reinforcing safety, stability, and specification compliance
Beyond its technical adaptability, the system enhances structural integrity by reinforcing unstable ground and safely transferring loads. Whether used for slope stabilization, retaining wall support, or foundation reinforcement, DYWI® Drill provides a robust, durable, and compliant solution trusted by engineers worldwide.
DYWI® Drill Hollow Bar applications
Slope stabilization
Reinforces natural or engineered slopes to prevent landslides, erosion, or settlement—especially in areas with loose or weathered soils.
Soil nailing
Creates in-situ reinforcement for retaining structures and excavation faces, delivering stability through friction and load transfer.
Excavation Support
Secures vertical cuts and trench walls during construction, allowing safe access and reduced risk of ground movement or collapse.
Rock Bolting
Provides anchorage in fractured or unstable rock masses, commonly used in tunnelling, mining, and cut slope stabilization.
Foundations and Underpinning
Enhances load-bearing capacity and provides additional support for new or existing foundations, particularly in weak or variable soils.
Micropiling
Forms small-diameter piles ideal for confined spaces, low headroom, or where minimal vibration and ground disturbance are critical.
Tunnel Face Support
Stabilizes tunnel headings during excavation by securing the face and surrounding ground, helping to maintain advance rates safely.
Temporary or Permanent Retaining Structures
Offers structural reinforcement for both short-term excavation walls and long-term retaining solutions in infrastructure or building projects.
