Repairs set to begin last night on the Woodrow Wilson Bridge were postponed for at least two weeks yesterday because of worries about the strength and durability of crucial materials to be used in the project, said Maryland highway administration officials.

Last night was to have been the first night of a 14-month project in which the bridge's six lanes would be reduced daily to two lanes between 8 p.m. and 6 a.m. so workmen could cut out pieces of the bridge's well worn roadway and replace them with new, precast concrete slabs.

James Bryce, project engineer for the Cianbro Corp., which is doing the $23 million redecking job, said officials were concerned about an experimental epoxy that coats the new concrete slabs.

He said the material, designed to protect the concrete from corrosive salts and chemicals used to de-ice the bridge in the winter, had recently satisfied officials, but that they asked for the material to be retested to double check the results.

"We'd rather be safe than put something on the bridge that's questionable," Bryce said. "I don't believe it's a serious problem."

Work has been rescheduled to begin Nov. 29. Meanwhile, all lanes will remain open.