In October 2010, a barge filled with 1500 t of scrap metal accidentally slammed into an electrical tower, hobbling the Houston Shipping Channel with a huge power outage and causing US$1 billion in overall damages and lost business. Centerpoint Energy called on Bo-Mac Contractors in 2012, to construct concrete barriers to protect the tower, in order to prevent future collisions.
Bo-Mac came to Cemex for help. “They called us for our technical expertise, and they basically wanted to know if it would be possible to put our cement (ready mix) trucks on barges to transport them to the pour site in the middle of the ship channel,” said Territory Account Manager Eric Edwards. “We had never done that before, but we were definitely willing to help them.”
The plan would require floating four trucks out to the repaired tower base, and then pouring small concrete barriers around it to prevent future incidents. The job was accomplished without issue, however, over time the barriers proved inadequate and more collisions occurred. Earlier this year Centerpoint Energy called Bo-Mac again to engineer a more permanent solution. Bo-Mac again contacted Cemex.
This time, the design for the new barrier system required 650 y3 of concrete, compared to the 40 y3 used on the first project. It would require six pours, two trips a day twice a week and up to six trucks for each trip. On top of that, market conditions added another factor, as the first project had occurred in a down-market.
“The current project requires so much more from everyone because of the scale, but also, ensuring delivery in a market as busy as Houston is now presents a challenge both Bomac and Cemex were willing to meet head on,” said Edwards.
An additional problem was posed by the one-and-a-half hour trip, as a mix that could go the distance without losing slump needed to be designed. “It required a mix design that could essentially be put to sleep,” said Edwards. “It was an opportunity for our Cemex team to showcase just what we were capable of doing. Safety, quality control and operations were notified, and we went to work.”
The team devised a 5000 psi mix that incorporated a high-range water reducer plus Recover 7, a set delay additive. The resulting mix provided the team up to seven hours to complete the pour before setting.
“Our team’s customer-focused approach to this project was the key to success. We are proud to have completed this unique and challenging project safely and successfully,” said Scott Ducoff, Cemex Regional President, Texas and New Mexico.
Extensive planning with the customer enabled the pour to be completed without problems. “It’s a great and exciting job for Cemex drivers,” said Warren Treadway, Area Manager. “The job is very organized and safety is a top priority at all times. Everyone enjoyed their ride on the barge and had a good time. Drivers hope we can get more jobs like this, because it shows that Cemex can accomplish anything.”
Adapted from press release by Rebecca Bowden
Read the article online at: https://www.worldcement.com/the-americas/17122015/cemex-helps-protect-electrical-tower-202/