Damage from landslides is common in Haiti. In Port-au-Prince, there is widespread destruction of nonductile concrete structures. Many rubble or unreinforced masonry walls failed. The E-in-plan Presidential Palace in Port-au-Prince still has much of the first floor intact, with windows unbroken, but there is total collapse above the first floor. There is very light reinforcing evident in failed columns near the entry. At the port, there is a collapsed pier and cranes, and several buildings are under water. Extensive lateral spreading and liquefaction is evident. These and numerous other on-site observations on damage from Haiti’s magnitude 7 earthqauke are from
Arch dams, classically curved monoliths situated in narrow valleys, are not as common as other types of dams, such as embankment dams and gravity dams. ENR takes a look at some of the biggest arch dams in the world, both completed and under construction.