what is the limitation/ restriction for B737-400 to land on 1800m runway?

Answer 1

Runways less than 2400m are equipped to provide RSFC - Runway Surface Friction Coefficient data to determine the stopping distance for normal landing configurations for heavy aircraft landings. Some airports have a portable RSFC kit which can be set up manually on the runway to collect surface friction data. The data collected is available on the Flight Planner Transport Webtrax Program.

Answer 2

Probably none, but no pilot would do it unless it was an emergency. It requires 2540 meters for takeoff at max weight.