Various Forms and Functions of Guardrails

Guardrails are a crucial component of road safety systems designed to protect vehicles and road users from hazards resulting from derailments, collisions, or extreme roadside conditions. Although often considered simply road barriers, guardrails come in many specific shapes and functions, tailored to the needs of their installation locations.

The following explains the various guardrail shapes and their functions.

1. W-Beam Guardrail

Shape:
A wavy "W"-shaped profile made of galvanized steel. Installed horizontally on vertical steel posts.

Function:
Absorbs vehicle impacts and steers vehicles back into the lane.

Commonly used on toll roads, overpasses, and sharp bends.

2. Three-Beam Guardrail

Shape:
Similar to a W-Beam, but with three waves, making it wider and stronger.

Function:

Prevents heavy vehicles or high-speed collisions

Often used in accident-prone areas and on steep slopes.

3. Cable Barrier (Cable Guardrail)

Shape:
Consists of steel cables installed horizontally on metal poles.

Function:

Flexible in absorbing impacts

Widely used on open roads, road medians, or intercity toll roads.

4. Box Beam Guardrail

Shape:
Box-section profile made of high-strength steel.

Function:

More rigid and resistant to strong impacts

Suitable for industrial areas or roads with heavy vehicle traffic.

5. Terminal End and Crash Cushion

Shape:
Special structure at the end of the guardrail, usually curved or equipped with impact dampers.

Function:

Absorbs collision energy to prevent fatalities

Placed at the ends of the guardrail or near road dividers that are prone to collisions.

Conclusion
The selection of guardrail types cannot be arbitrary. It must be adapted to road conditions, traffic volume, and potential hazards in the surrounding area. The right guardrail design can reduce the impact of accidents and save lives.

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