EL LABERINTO, Venezuela—A thousand abandoned concrete huts dot a plain beneath a remote mountain range here in western Venezuela, surrounded by empty, rusting silos and irrigation canals covered with weeds.

This is the Diluvio agro-industrial commune, built with $2 billion of Venezuelan capital by Brazilian construction giant Odebrecht SA, which last month admitted to giving out almost $800 million in bribes to secure contracts in 12 countries, including Venezuela.

The administration of late President Hugo Chávez awarded Odebrecht $11 billion in contracts to build communes like Diluvio in remote parts of the country and connect them to the heartland with grand bridges and railways, according to company employees and state documents.

But while the company completed roads, pipelines and railways elsewhere in Latin America and Africa, few of the dozens of projects contracted under Mr. Chávez came to fruition.

“They were throwing money by the billions into projects that were never going anywhere,” said a civil engineer who worked for Odebrecht at Diluvio.