Steel and reinforced concrete structures

Design of steel and reinforced concrete structures for power infrastructure 

Support structures are a critical component of the power transmission system, enabling the routing of overhead power lines and the mounting of key system parts. For the construction of new transmission lines and substations, or the modernization of existing infrastructure, a prerequisite for initiating any work is the preparation of complete technical design documentation for the associated structures. Alterga provides a wide range of services in this field.

One of the primary types of support construction in power systems is utility poles. The key differentiator between poles is the type of material used. The choice of structural material largely depends on the voltage class of the transmission line. High-voltage (HV) lines typically utilize steel lattice structures, which are generally the tallest and have the largest footprint. Steel structures are also widely used in the construction of telecommunications towers. Alterga’s engineering services include the design of both power transmission and telecom tower structures.

On the other hand, reinforced concrete structures are more common in medium- and low-voltage (MV/LV) networks. The design of each structure must account for material specifications, height, selection of accessories, and proper foundation design. All energy infrastructure structures must meet strict strength and stability requirements, in accordance with national and European standards and regulations. These include, but are not limited to:

• PN-EN 61936-1 – General requirements for high-voltage installations
• PN-EN 50522 – Earthing of power installations
• Eurocodes:
• PN-EN 1992 – Design of concrete structures
• PN-EN 1993 – Design of steel structures
• PN-EN 50341 – Overhead high-voltage lines
• Industry-specific standards, such as those from PSE (Polskie Sieci Elektroenergetyczne)

Adherence to these standards ensures the safety, reliability, and regulatory compliance of power infrastructure projects, and is a compelling reason to engage professional design services.

Key aspects of power structure design 

The preparation of structural design documentation involves numerous technical considerations. One of the most important factors is the terrain where the structure will be installed. Depending on the soil and hydrogeological conditions, the foundation of a transformer station may require subgrade improvement – through soil replacement, reinforcement, or the application of shallow or deep foundation systems (e.g. piles) – to ensure the required load-bearing capacity and structural stability. These factors must be accounted for in the technical design documentation of transformer station foundations.

Alterga leverages a broad range of tools and engineering expertise in its design processes. We conduct all necessary geodetic and geotechnical surveys, provide expert technical consulting, and use state-of-the-art engineering software throughout the design phase. This includes advanced tools such as:

• PLS-CADD and PLS-Tower – for transmission line and tower modelling
• IdeaStatica – for steel and concrete design
• Autodesk Robot Structural Analysis Professional (ARSAP) – for structural analysis using the finite element method (FEM)

These tools enable detailed static and strength simulations under various load scenarios, including wind, ice accretion, conductor tension, and soil-structure interaction.