Project Title: CONSTRUCCION AMPLIACION ESTACION TRANSFORMADORA LEONES 132/66Kv - Tramo 132kV Linea Alta Tension. Obra Publica.
Company: Cordoba Provincial Energy Company.
Location: Leones, Córdoba, Argentina.
Date: January 2018.
Period: 5 months.
This episode details my technical contribution to an urban infrastructure initiative aimed at enhancing the quality of electricity service in the town of Leones and its surrounding area, serving approximately 11,000 residents.
The project entailed the expansion of the Leones Transformer Station (ET) from 66 kV to 132 kV, the integration of a new 1x40 MVA field, and the construction of a 132 kV overhead transmission line segment.
The project was financed by provincial public funds, with a total cost of USD 1,532,248 and a completion time of 270 calendar days.
As the civil engineer responsible for the technical supervision of the project, I assumed direct responsibility for compliance with technical, regulatory and ethical standards, which included:
Ensuring structural safety and the quality of construction processes, especially in a critical project for the provincial electricity system.
Ensuring the technical traceability of each stage: from the control of materials and tests, to the verification of the design and final execution.
Supervise compliance with current regulations such as CIRSOC, IRAM, ISO and API, and the requirements of the tender documents.
Provide technical information to the client on any technical deviation, proposing well-founded solutions, and anticipating construction risks.
Approve progress certifications based on technical compliance and not merely on physical progress, upholding the principles of fiduciary responsibility and transparency.
This project represented a clear demonstration of my professional judgement, technical leadership skills and commitment to ethical engineering.
During the execution of the bored piles for the extension of the Leones Transformer Station, we faced a critical technical challenge related to the stability of the deep excavations. The piles, approximately 16 metres deep and 1.2 metres in diameter, were driven using bentonite slurry as the stabilising fluid. From a depth of 12 metres, partial failures were identified in the walls of the shafts, which caused slippage and increased the risk of collapse prior to concreting.
Through direct observation, drilling reports and mud analysis, I determined that the soil at that level had saturated fine sand strata with intercalated layers of silt, characterised by high permeability and low cohesion. This condition favoured the loss of bentonite fluid into the ground, which reduced the hydrostatic pressure within the borehole and compromised the structural integrity of the pile.
The risks were significant: loss of shaft section, reduced bearing capacity, difficulty in inserting the reinforcement and contamination of the concrete with loose material, which endangered the stability of the entire foundation system.
Faced with this situation, I proposed and coordinated a series of technical corrective measures:
Adjusting the bentonite sludge
I performed intensive monitoring of the sludge properties, using tools such as the Marsh Funnel, API sludge balance and Filter Press. We increased the sludge density to 1.12 g/cm³ and the viscosity to over 45 seconds per litre, improving the lateral holding capacity. We also incorporated stabilising additives to reduce fluid seepage in permeable soils.
Controlled natural filter formation
I established a technical pause procedure during excavation, allowing a bentonite film (cake) to form on the borehole walls, which acted as a natural waterproof barrier. This measure reduced fluid losses and stabilised the surrounding ground.
Reinforcement of the cleaning and concreting process
I coordinated the cleaning of the bottom of the shaft with a bailer to remove sediment and ensure proper bonding of the concrete. I established a rigorous protocol for concreting with tremie pipe, ensuring a continuous flow from the bottom of the pile upwards, which prevented segregation, air ingress and contact with residual sludge.
Constant monitoring and quality control
I designed a system for daily monitoring of slurry parameters before, during and after excavation. In addition, I managed the execution of PIT (Pile Integrity Test) tests to verify the structural continuity of the shaft and validate the effectiveness of the measures taken.
Thanks to these actions, it was possible to stabilise the excavations, guarantee the verticality of the piles and carry out the concreting without contamination or loss of volume. Integrity tests confirmed that all structural elements were within the expected technical tolerances, thus ensuring the reliability of the transformer station foundation.
I fulfilled all the objectives assigned to the project.
I also developed Gant Diagrams with an exhaustive monitoring procedure and knowledge within the field of this type of work.
I experienced my first supervisions in deep foundations, at more than 16 meters, with the presence of bentonite mud.
I worked with an interdisciplinary team of architects, builders and contractors.
Regulations:
I interpreted and applied the Particular Conditions of the Contract and the General Technical Specifications for Public Works in force in the Province of Cordoba, ensuring technical compliance at each stage of the work.
I ensured the execution in accordance with Decree No. 418/86, which establishes the "General Conditions for the Execution of Public Works by Third Parties and for the Account and Order of the Provincial Energy Company of Cordoba (EPEC)", and its amendments.
I supervised compliance with the principles established in Provincial Law No. 8614 - Public Works Law, ensuring transparency, traceability and professional responsibility.
I verified minor civil works (walls, bases, administrative building) according to Ordinance Nº 9387/95 - Building Code of the Municipality of Cordoba.
I applied IRAM standards for the evaluation of reinforced concrete structures, material resistance, testing procedures, and durability in electrical works.
I evaluated laboratory tests and acceptance criteria according to the requirements of the technical specifications and the IRAM 50000 and 60000 series.
Software:
AutoCad: reading, revision and adjustment of structural drawings and construction details. I checked interferences between foundations, piping and support structures.
Revit: I applied this software for three-dimensional visualisation of interferences between electromechanical and civil elements in the extension of the administrative building and the transformer base.
Microsoft Excel: I performed metric computation calculations, official budget, cost structure spreadsheet and unit price analysis. I also managed the technical-economic monitoring of the work and prepared physical progress control spreadsheets.
S.I.G.O. (Integrated Works Management System): I used this system of the Province of Cordoba to record work progress, upload certifications, issue technical reports, and generate alerts on deviations in the schedule.
ORACLE (EPEC's internal system): I operated this system for the management of technical documentation, material approvals, certification entry and contractual traceability.
Plans of foundations, construction details, sections, and building.
Calculation memorandums.
Site photographs.
Internal certifications.
Management system documents.
Site plan / Task diagram.
Public Tender Documents
Diagram of tasks
Documentation of test tubes
ABOUT THE PROJECT
The work was executed within the established contractual deadline of 270 calendar days, meeting the milestones of the overall schedule without critical delays. The cumulative physical progress exceeded 95% within the deadline, and the certified economic progress reached 93%, reflecting an efficient execution aligned with the technical-financial planning.
It should be noted that the site was located in an area at risk of temporary flooding, especially during periods of heavy rainfall. For this reason, preventive actions of surface drainage, levelling of the terrain and controlled compaction were implemented from the initial stage to ensure the trafficability of vehicles and equipment, as well as the stability of foundations.
Thanks to rigorous technical supervision and the correct interpretation of site constraints, it was possible to avoid cost deviations. The differences between the official budget and the final construction cost remained below 5 %, which was positively acknowledged by the client.
ABOUT ME
Comencé mi participación en esta obra mientras me encontraba en la etapa final de mi formación universitaria, desarrollando en paralelo mi tesis de grado en Ingeniería Civil. Esta experiencia representó un gran desafío personal y profesional, ya que debí combinar mis últimas responsabilidades académicas con la supervisión técnica en una obra de alta exigencia, vinculada directamente a la infraestructura energética provincial.
Este proceso me permitió aplicar en el campo muchos de los conocimientos adquiridos en mi formación, especialmente en geotecnia, estructuras, normativa técnica y planificación de obras. Al mismo tiempo, reforzó mi disciplina, mi compromiso con la ingeniería y mi vocación por la gestión de proyectos complejos desde una perspectiva integral.