Poorly Executed Surveys: Hidden Risks in Energy Transmission Projects

Geotechnical investigation through percussion drilling (Standard Penetration Test) is a critical stage in the development of transmission line projects, being essential for the proper design of the foundations of metal structures. Obtaining accurate data on subsurface conditions along the route allows for the geotechnical characterization of the terrain, supporting design decisions based on technical and regulatory criteria. In summary, the geotechnical survey not only technically underpins the foundation design but also contributes to the technical, economic, and operational feasibility of the project, being indispensable for the safety and durability of transmission lines. This study will demonstrate two important examples of how a geotechnical investigation conducted in accordance with standards, properly planned and executed, will positively contribute to a clearer, more conscious, and highly effective civil transmission line project, completed within the planned schedule and estimated budget. This article will highlight the relevance and effectiveness of geotechnical surveys as a fundamental stage in the development of transmission line projects, analyzing how erroneous data can compromise the civil project in terms of technical study, increased project and construction costs (CAPEX), and schedule impact. It will also address how poor execution of the geotechnical campaign leads to rework in project development and potential negative impacts on the operation of the asset due to undersized foundations, where inconsistencies in the surveys are not identified before energization (OPEX), resulting in future extra costs and accelerated depreciation of the transmission company's assets. For the development of the analyses, the initial percussion drilling conducted for the case study projects were compared with the results of a second geotechnical campaign, demonstrating a significant variation in soil resistance, leading to foundation underdesign and increased in the civil quantity project. The civil project begins with percussion drilling results. An error in your execution, if not in accordance with standard ABNT