With the increasing number of engineering projects in complex geological conditions, traditional single support methods often fail to meet safety and stability requirements. The combined support system of self-drilling anchor bolts and protection nets has been widely adopted due to its high construction efficiency, strong adaptability, and stable performance.

Protection net systems are generally divided into two categories based on their mechanical behavior and working mechanism: active protection nets and passive protection nets. The differences between them are mainly reflected in working principles, support strength, protective capacity, construction methods, applicable scenarios, and cost. Below is a detailed comparison of how self-drilling anchor bolts interact with these two systems.

1. Working Principle Comparison

1.1 Self-drilling anchor bolts + Active protection nets

In this system, self-drilling anchor bolts are used to fix and tension the protection net, forming an actively reinforced support structure. The tension force is transmitted through steel wire ropes and mesh components and anchored by the bolts.

The anchoring force significantly improves overall structural stability and resistance to external forces. Through continuous pre-tensioning, the active protection net system constrains the rock and soil mass, preventing loosening and movement, thereby enhancing slope and surface stability.

1.2 Self-drilling anchor bolts + Passive protection nets

In this system, self-drilling anchor bolts mainly serve as fixing and supporting elements. The passive protection net relies on its own elasticity and flexibility to absorb and dissipate impact energy.

The bolts secure the net to the rock or ground surface, ensuring it can intercept falling or sliding debris and distribute impact forces. Unlike active systems, passive protection nets do not rely on pre-tensioning but instead resist external forces through elastic deformation.

2. Support Strength and Stability Comparison

2.1 Active system combination

The combination of self-drilling anchor bolts and active protection nets provides higher support strength and overall stability. The system enhances reinforcement through tensioning and is suitable for unstable geological conditions such as weak rock layers, loose soil, and steep slopes.

It is highly effective in preventing large-scale hazards such as landslides and rockfalls.

2.2 Passive system combination

When combined with passive protection nets, the overall support strength is relatively lower. Although self-drilling anchor bolts provide stable anchoring points, the system mainly relies on the nets flexibility to absorb impact.

Since passive systems do not impose continuous tension on the rock mass, they are more suitable for relatively stable geological conditions and low-energy rockfall control.

3. Protective Capacity Comparison

Active protection nets

Active protection nets provide strong protective performance, especially against high-impact events such as large landslides, rockfalls, and seismic activity. Pre-tensioning allows the system to effectively redistribute external forces and limit large-scale deformation.

They are widely used in high-risk areas such as mountainous slopes, mining zones, and tunnel engineering projects.

Passive protection nets

Passive protection nets have more limited protective capacity and are mainly used in low-risk and stable environments. Their primary function is to intercept small rockfalls or minor soil movement by absorbing impact energy through deformation.

They are suitable for small mines, landscape protection, and controlled slope areas.

4. Construction Method Differences

Active protection net construction

Installation requires precise placement of self-drilling anchor bolts, steel cables, and mesh systems. Pre-tensioning must be adjusted according to geological conditions using specialized tensioning equipment.

Compared with passive systems, construction is more complex and requires higher technical standards, equipment, and labor input.

Passive protection net construction

Passive systems are easier to install. The net is directly laid on the slope or rock surface and fixed using self-drilling anchor bolts.

No tensioning process is required, making construction faster, simpler, and more cost-effective.

5. Application Environment Differences

Active protection nets

Active systems are suitable for high-risk areas and complex geological conditions, such as steep slopes, weak rock formations, and unstable soil layers.

Combined with self-drilling anchor bolts, they significantly improve resistance to earthquakes and slope failure. They can provide continuous support even under extreme weather conditions such as heavy rainfall.

Passive protection nets

Passive systems are better suited for relatively stable geological environments, including gentle slopes and intact rock formations.

They are mainly used for small-scale rockfall prevention and are not suitable for large landslide control or high-demand engineering support requirements.

6. Cost Comparison

Active protection nets

Due to the use of steel cables, wire mesh, and tensioning operations, active systems have higher construction and installation costs. They require more equipment, labor, and maintenance.

However, their superior protective performance makes them cost-effective for high-risk, long-term engineering projects where safety is critical.

Passive protection nets

Passive systems have lower installation and maintenance costs due to simpler construction methods and fewer equipment requirements.

They are highly cost-effective for small-scale or low-risk projects, providing sufficient safety at a lower investment level.

Conclusion

When self-drilling anchor bolts are combined with either active or passive protection net systems, the differences become very clear.

Active protection nets are suitable for high-risk and complex geological environments. They offer strong reinforcement and protection but come with higher cost and construction complexity.

Passive protection nets are suitable for relatively stable conditions. They are easy to install and cost-effective, mainly used for small rockfall or minor soil movement control.

In practical engineering applications, the selection of a protection system should be based on comprehensive evaluation of geological conditions, risk level, and project budget to determine whether an active or passive system is more appropriate.

Categories

Slope Stabilization

Keywords

slope stability analysis, slope, Slope Failures