パナマ運河の拡張工事で、建設費用の増大の原因：泥、コンクリート、玄武岩
La causa de los sobrecostes del Canal de Panamá: lodo, basalto y hormigón
Sacyr considera que el pliego de la licitación contenía errores muy graves y costosos
El consorcio ha solicitado un retraso del plazo de la obra hasta febrero de 2016
Miguel Jiménez Madrid 12 ENE 2014 - 00:02 CET
The cause of the extra Panama Canal: mud, concrete and basalt
Sacyr considers the bid specifications contained serious errors and costly
The consortium has requested a postponement of the deadline of the work until February 2016
Miguel Jiménez Madrid 12 ENE 2014 - 00:02 CET
Sacyr because of the extra cost of construction of the third set of locks of the Panama Canal to the poor information provided in the specifications . The geological differences and some changes in specifications are those that have generated those extra the consortium Grupo Unidos por el Canal ( GUPC ) stands at $ 1,625 million ( 1,200 million) costs. These were the major problems of the work:
Mud in the cofferdam
The consortium had to build a cofferdam or temporary dam at the entrance to the new set of locks on the Pacific side to run the excavation , concreting and packing the new structures under sea level , dry and safe . Cofferdam That is why , the first job the first work to be performed and executed directly on the ocean waters . information said there was competition to build the cofferdam valid to 6 feet below the mean level of Pacific material. But to start foundation work , GUPC saw that valid ground for the foundation had been dredged by the Panama Canal Authority (ACP ) and replaced over time with sludge foundation of Cocolí river. The consortium had to dredge the sludge , cement to 13 meters below sea level and build a cofferdam wider at the base and higher than expected, with a cost overrun of $ 120 million .
basalt poor
Sacyr explains that the hypothesis assumed that ACP basalt excavations Pacific side serve as own source of aggregates for concrete work , once crushed and processed. GUPC purchased and installed a crushing plant , but saw that the fractured basalt unexpected and excessive amount of fine plastic material nature , which caused him serious problems generated. That change meant crushing plants , forced to locate and exploit new sources of basalt and lead to unnecessary landfill materials. Sacyr believes that because the real nature of the basalt was not disclosed in the bidding and its properties were unpredictable , the consortium is entitled to recover additional costs by $ 497 million .
Concrete for 100 years
The primary requirement for concrete locks is to have a lifespan of 100 years. The specifications did not indicate a particular methodology to demonstrate the durability , but some technical criteria. The test established a maximum permeability of 1,000 coulombs of current in a trial with an international standard. But no specifications concretaban age of concrete at the test , a key requirement was made because most of the properties of concrete ( including waterproof and chlorine) improve with time , as the hydration process progresses . GUPC assumed that the concrete could pass the test with a year old , which was well before it comes into contact with chlorine from salt. But the ACP demanded , not contained in those specifications that fulfill these requirements in a shorter period , why rejected the option of the consortium , who had to use new formula with additives such as silica fume, common in high-strength concrete . This material makes it difficult to work with concrete, accelerates the setting and increases the heat released , which requires adding ice mixtures and refrigerate aggregates. All these problems generated cost overruns and delays. Concrete problems with other disorders, interference and modifications have resulted in a claim for 880 million dollars.
Besides economic claims , the consortium has requested an extension of time of 16 months until February 2016. For problems with provisional dam cofferdam or requests within 120 days , and the basalt and concrete, the requested extension is 365 days. therefore, a total of 485 days on the original deadline for delivery of the work , which was the October 21, 2014 .
However, the plan of work includes the work completed on June 30, 2015 , with a delay of 220 days, which Sacyr attributed to " acceleration measures " : more investment, more equipment, more staff. That is, after the initial date , but before it considers the delay justified. If he manages to GUPC recognize the new deadlines , and finish the work by 2015 would be entitled to a premium or bonus of $ 215,000 for each day in advance, with a maximum of $ 50 million . However, if you recognize any delay justified , the penalty is $ 300,000 for each day of delay with a maximum of $ 54.6 million .
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