LUCKNOW, Sept. 22 -- The cracks and sinking may have been repaired, but the question of why the Lucknow-Kanpur Expressway began failing within weeks of opening remains unanswered, with NHAI still awaiting an IIT Kharagpur report 43 days after its inspection.

The IIT team inspected the greenfield corridor in the first week of August and collected around 80 samples from the pavement and underlying layers for laboratory tests. But as of Monday, the detailed technical report had not reached the National Highways Authority of India (NHAI).

The report is expected to establish whether the premature failures were linked to pavement structure, subgrade preparation, drainage, construction methodology, material quality or a combination of factors....