A structural joint includes inner preforms 20, 22 and outer preforms 24, 26 of material. The outer preform has legs 38, 40 that extend longitudinally and laterally from a fold 42. The inner preforms project longitudinally past the fold to define a spar 44. A wing, such as wings 50, 52, 54, 56, extends from the spar. The spar and wing cooperate with a substructure to resist separation of the spar and wing from the substructure. The joint is described in the context of a duct, such as a turbine engine inlet duct, but may be used in other applications.