Corrosion Protection of Rock Anchor Bolts: Ensuring Longevity in Support Projects

Rock anchor bolts play a vital role in providing stability and support in various construction projects, particularly in challenging geological conditions. However, the exposure of these anchor bolts to corrosive elements can significantly compromise their structural integrity and lifespan. To ensure the long-term effectiveness of anchor bolts, it is crucial to implement appropriate corrosion protection measures.

Rock Anchor Bolt Corrosion Protection Requirements for Support Projects

service life of different types of rock anchor bolt

1. Temporary Support Projects

Temporary supporting structures are those structures that are required in routine building construction works or repair works. During the process of excavation, or temporarily supporting a weak structure some temporary structures are constructed which is called shoring. Temporary support projects generally refer to those with a time of duration less than 2 years. If the geological environment is not corrosive can choose no corrosion protection of the rock anchor bolt, if belongs to a corrosive environment need to use a Level II corrosion protection rock anchor bolt.

2. Semi-Permanent Support Projects

Semi-Permanent support projects generally refer to those lasting between 2-5 years. Semi-permanent support projects require a higher level of corrosion protection. Geological environments that are non-corrosive require Level Ⅱ corrosion protection rock anchor bolts, while corrosive environments require Level Ⅰ corrosion protection rock anchor bolts.

3. Permanent Support Projects

Permanent support projects, which refer to those projects lasting more than 5 years, require the most robust corrosion protection. In such instances, Level Ⅰ corrosion protection rock anchor bolts, like stainless steel rock anchor bolts, hot-dip galvanizing rock anchor bolts, and double corrosion protection rock anchor bolts are commonly used.

Types of Corrosion Protection for Self-drilling Anchor Bolts

1. Stainless Steel Self-drilling Anchor Bolts

Stainless steel self-drilling anchor bolts offer excellent corrosion resistance properties, making them ideal for permanent support projects. These bars are manufactured from high-quality stainless steel alloys, such as 316 material, which provide superior resistance to corrosion in various environments and can resist corrosion in air or chemical corrosion conditions.

2. Hot-dip Galvanizing Self-drilling Anchor Bolts

Hot-dip galvanizing is a widely used method for protecting steel from corrosion. In this process, the anchor bars are immersed in molten zinc, creating a durable zinc coating that acts as a barrier against corrosive elements. Hot-dip galvanizing is a cost-effective corrosion protection method suitable for both permanent and semi-permanent support projects. These bolts are resistant to acid and alkali mist corrosion and are often used in complex environments with high demands on product life.

3. Double Corrosion Protection Self-drilling Anchor Bolts

For projects that require the highest level of corrosion protection, double corrosion protection self-drilling anchor bars are an excellent choice. These bolts integrate two anti-corrosion processes of hot-dip zinc and epoxy coating. The bars are first hot-dip galvanized and then epoxy coated on their outer surfaces. This combination ensures maximum durability and longevity in harsh environments, not only can resist ordinary chemical corrosion but also in the acidic environment and stray current electrochemical corrosion work.



Support projects utilizing rock anchor bars require careful consideration of corrosion protection due to the corrosive nature of the surrounding rock and soil. The level of corrosion protection needed depends on the characteristics of the stratum and the desired service life specified in the design. By implementing effective corrosion protection, the anchor bars can withstand the test of time, ensuring the safety and stability of the supported structures.
Sinorock can provide high-quality corrosion-resistant self-drilling anchor bolts, customized to match your needs and make geotechnical anchoring projects safer and more efficient, get in touch at

Return The List

latest news