By Francis C. Felizardo, PhD
When it delivered the last concrete load to the 29th Burgos Wind Farm (BWF) tower mat foundation on March 6, the newly-organized First Balfour Concrete Division successfully completed its first major project.
“This is the result of a lot of hard work by our engineers, supervisors, drivers and field personnel,” said Division Manager Roberto P. Aledia, Jr. “We really benefitted from our good working relationship with our client, the First Balfour BWF Project Team, the consultants, and our suppliers.”
A major part of the BWF civil works is the construction of 29 wind turbine tower foundations, each requiring 630 m3 of concrete per tower, mat, and pedestal. Equipped with 2 concrete pumps and 16 transit mixers, the First Balfour Batching Plant had a nominal capacity of 90 m3 of concrete per hour and has produced a total of 23,000 m3 of concrete.
We set up two batch plants so if one broke down, operations could still continue. Because we always looked for ways to improve, by the end of the project, we could complete a mat in less than 8 hours.
We also had to demonstrate to our client that the large mat foundations will not have thermal cracks, a potential durability problem. Together with TCGI, our structural consultant, we developed a mathematical model that predicted heat generation during concrete hardening. We then showed that our structural design sufficiently addressed the issue. We installed thermocouples in some of the mats to measure their interior concrete temperature and reconfined our model.
For the Concrete Division, the BWF Project was successful operationally and financially. The Division plans to use this experience as a model for future engagements and to help the company succeed in its other projects.