Did concrete reinforce Chinese junk hulls?

Did Chinese junks use concrete to strengthen their hulls against hogging and sagging?

The claim is not confirmed. Bamboo reinforcement is recalled uncertainly, and the surviving information about the large treasure ships is considered insufficient.

A viewer proposes that concrete helped Chinese wooden hulls resist hogging and sagging. The reply recalls hearing of bamboo reinforcement within concrete, but does not confirm the account. Evidence for the large treasure ships is described as too limited to establish their construction confidently. Their possible size makes unusual construction plausible as a hypothesis, without proving the method.