Specifications and models of handholes for optical cable lines

Handholes are underground access points for fiber optic cables, available in various materials, sizes, and load-bearing capacities to suit different installation environments.

Overview of Handholes

A handhole is a small, underground enclosure designed to provide access to buried fiber optic cables, conduits, or other utilities for splicing, pulling, or maintenance operations. Unlike manholes, handholes are typically shallow and do not allow full personnel entry, serving primarily as junctions, pull points, and storage for slack cable loops. They are essential for network expansion, maintenance, and safety, reducing the need for extensive excavation and minimizing service disruption.

Types of Handholes

Fiber Optic Handholes Specifically designed for fiber optic networks, these handholes include internal brackets or racks to manage slack loops and fiber enclosures. They are often made from composite materials, polymer concrete, or HDPE, offering lightweight, durable, and corrosion-resistant solutions. Electrical Handholes Used for underground power cables, typically constructed from high-strength concrete or composite materials with grounding features.

Precast Concrete Handholes Standardized in size, these are durable and suitable for high-traffic or load-bearing applications, often used in roads or industrial areas.

SM

C Composite Handholes Made from Sheet Molding Compound (SMC), these handholes are quick to install, resistant to high and low temperatures, corrosion, and provide high load-bearing capacity. They are suitable for backbone optical cable networks and can be used in both non-vehicular and vehicular areas depending on the model (e.g., A50, B125, C250),. MaterialsHDPE (High-Density Polyethylene): Lightweight, corrosion-resistant, ideal for parks, sidewalks, and green spaces.

Polymer Concrete: High compressive strength, lighter than traditional concrete, suitable for medium-duty applications. Precast Concrete: Heavy-duty, durable, suitable for roads and high-traffic areas.

SM

C Composite: Quick installation, high strength, corrosion-resistant, suitable for backbone networks.

Sizes and Load Ratings

Handholes vary in size depending on their function: Splice Handholes: Larger to accommodate slack loops, splice closures, and installation tools. Must respect the cable's minimum bend radius. Intermediate Handholes: Smaller, used for cable routing or future splicing; should still allow slack storage.

Load ratings are classified according to usage: A50: Non-load-bearing, suitable for green spaces or residential areas. B125: Light motor vehicle traffic, suitable for roads and parking areas. C250: Heavy-duty, for motor vehicle roads and high-traffic zones.

Installation Considerations

Innerducts should enter near corners to maximize usable space for coiling cables. Handholes should be sized to allow future network expansion. Material choice depends on environmental conditions, traffic load, and installation location.

Lightweight materials like HDPE or polymer concrete reduce installation effort and cost, while precast concrete or SMC composites provide higher durability and load-bearing capacity.

Summary

Selecting the right handhole involves considering material, size, load rating, and intended use. For fiber optic networks, composite, polymer concrete, and HDPE handholes are common for light to medium-duty applications, while precast concrete and SMC composite handholes are preferred for heavy-duty or backbone installations. Proper sizing ensures sufficient space for slack storage, splicing, and future network expansion, while material choice ensures durability and cost efficiency.