Field Test on the Lodging and Uprooting Conditions of Casuarinas and Verification of Those through the 2010 Mentawai Earthquake Tsunami

Damage to Reinforced Concrete Buildings and Coastal Trees Due to the 2011 Off the Pacific Coast of Tohoku Earthquake Tsunami

“…Figure 12 shows a relationship among the chest height diameter D of coastal black pine tree, inundation depth h and damage type (Lodging: •, Uprooting: ▲, Breaking: ◆, Withstanding: □) of the tree. The figure indicates that 1) although the transition region where the damaged and the withstood were mingled is considerably large, both are relatively well classified by the chest height diameter and the inundation depth, 2) as the ratio of the inundation depth to the chest height diameter becomes large, a tendency of the breaking becomes strong, 3) it is the same in the case of evergreen tree Sea Casuarina (another name 'coastal pine') in Indonesia [Matsutomi et al, 2011] that the breaking data extend over both domains of the lodging and uprooting, and 4) the force at the uprooting tends to be smaller than that at the lodging. It is conceivable as the reasons of the result 4) that the main root which spreads laterally broke at a lodging stage besides the ground condition and ground water level.…”

“…(3) and damage type of the tree. In the figures, the upper limit conditions of the lodging (solid line) and uprooting (dotted line) obtained by a field test for the lived Sea Casuarina carried out on the west coast of Central Sumatra, Indonesia [Matsutomi et al, 2011] are also shown. As will be seen from Fig.…”