For Immediate Release January 2002 Shotcrete Meets Challenge of Huge Water Project in Ecuador By replacing traditional "form and pour" methods with high production shotcrete, the massive Trasvases Manabi Water Project in Ecuador finished months ahead of schedule. Contractor Norberto Odebrecht in conjunction with Shotcrete Technologies Inc., of Denver, Colorado, and Commercial Shotcrete Inc., of Phoenix, Arizona placed over six thousand cubic meters of shotcrete in less than half the time it would have taken by the specified method, and put the project a whole rainy season ahead. The Trasvases Manabi Water Project's goal is to optimize that country's seasonal rainfall patterns by linking a trio of reservoirs and by constructing pipelines and transfer and delivery tunnels to control water distribution. The end result will be a constant supply of water for drinking, irrigation, and industrial use. General Contractor Norberto Odebrecht from Brazil was hired by the Centre de Rehabilitacion (CRM) of Manabi, the government agency responsible for water improvements. Odebrecht is the largest contractor in Brazil with more than 42,000 employees on the payroll. Arriving on site in May of 1999, Odebrecht was charged with the responsibility of constructing a pumping station to lift water from La Experanza reservoir into a pipeline that feeds into an 11.4 KM long tunnel and discharges into the Poza Honda reservoir to the Mancha Grande River, both to increase the water supply to Portoviejo, the principal city of the province and the surrounding regions. By July of 2001, the project was five months ahead of schedule, and Danilo Abdanur the construction manager for Odebrecht, began to realize that they could perhaps complete the entire project by the Rainy season (late November). The logistical challenge to maintain the "ahead of schedule pace" on this $140 million-dollar project called for some creative solutions. To complete the project by the end of November, 2001 the spillway walls of the Conguillo dam portion of the project had to be erected. At twenty five meters high, sixty and one hundred centimeter thick walls with a 1% tolerance and minimum of six thousand cubic meters to place, traditional form and pour would not meet Abdanur's aggressive schedule. Kristian Loevlie, of Shotcrete Technologies Inc., was called in to visit the site and meet with Odebrecht, the Owners, and Engineers to discuss the possibility of erecting these massive walls using shotcrete. Having done high volume shotcrete projects all over the world, Loevlie explained that good shotcrete is a high quality "in-place" concrete, often with much higher compressive strength. The Group was convinced that this was the answer to their dilemma and a unanimous decision was made to go full speed ahead with shotcreting the entire 6000 cubic meters. Time was of the essence and Shotcrete Technologies quickly pulled all the logistics together including: application experts, various mix designs, local supply of materials - sand, aggregate, plasticiser, and then training local laborers to execute the shotcrete application and finish. A local naphthalene based Superplastisizer was used and ST-ALKALI Free Accelerator was used for water control and temporary ground support. Commercial Shotcrete Inc. of Phoenix, Arizona was chosen to partner with Shotcrete Technologies and Odebrecht and supply equipment as well as expertise and supervision to train and work with the shotcrete crews. Developing a good consistent shotcrete mix for this scope of work is vital to the success of the job. Odebrecht had their own batch plant on site making it relatively simple to test all the mix components. After trying various sands, aggregates, cements, and using as many local materials as possible, the team came up with a workable/pumpable design which included: > 420 kg. Cement > 440 kg. 10 mm aggregate > 1130kg. Sand > 1.7% naphthalene super/plasticiser > W/C ratio of .45 The mix design strength was 24 MPA, and in-place testing produced 32 MPA on average. Once Commercial Shotcrete's REED pumps arrived, the first two weeks were primarily focused on training the locals on shotcrete technique. Alberto Medina, General Manager, and various supervisors from Commercial Shotcrete supervised the entire application process, from training the crews to nozzling and pumping and setting up guide wires and finishing. As soon as the training was accomplished crews reached a daily production rate of more than 180 cubic meters of shotcrete using two pumps on two shifts. The shotcrete was placed through rebar and mesh (as specified) directly on a twenty-five meter high dirt excavation requiring extensive temporary support. By using shotcrete, the initial support and final one meter thick structural walls were done simultaneously. This continuous process of excavation, reinforcement, initial support, and final structure was very fast, efficient, and cost effective, and shaved months off the time traditional methods would have taken. By the end of November, the spillway walls were finished and ready for the rainy season. According to Danilo Abdanur, Construction Manager for Odebrecht, the key to the project's success was choosing the proper equipment, setting up an efficient working site, mobilizing adequate support equipment, having a knowledgeable crew, a workable and consistent mix design and adhering to a daily maintenance routine. However, the biggest factor, was taking the perceived risk on a technology that he had not used for this specific type of application. Odebrecht also claimed a record for TBM advance following breakthrough of the project's 4.6 km. Transbasin tunnel. The Trasvases Project is one of the many innovative projects around the world for which Shotcrete Technologies, Inc. is known. For further information contact Shotcrete Technologies at 303.567.4871 or Commercial Shotcrete Inc. at www.fishershotcrete.com.