Performance of Structures in the Mw 6.1 Mae Lao Earthquake in Thailand on May 5, 2014 and Implications for Future Construction

An M_w 6.1 earthquake struck northern Thailand on the 5^th of May 2014. The epicenter was located near Mae Lao district in Chiang Rai province. The earthquake caused unprecedented damage to structures, the most damaging earthquake ever in recorded Thai history. Five hundred and ninety-four buildings out of 10,863 were damaged to the extent that they were unsafe for occupancy. This article presents a reconnaissance investigation of damage to buildings and bridges in the two districts—Phan and Mae Lao—which suffered the most damage. Attention is paid to the performance of buildings with similar configurations and structural design, but with different layout of unreinforced masonry infills as non-structural components.     

Alaska

The paper reports on results of an experiment concerned with assessing the cartographic accuracy of an optically processed spaceborne synthetic aperture radar (SAR) image taken over a very hilly area in the Scottish Highlands. A number of mathematical algorithms were used to transform the image to the terrain co‐ordinate system. The results show that it is indeed possible to extract metric information from this type of imagery to suit the purposes of small‐scale reconnaissance‐type planimetric mapping at 1:250,000 and smaller. This is important for many developing countries where topographic coverage is either poor or completely absent.     

Geotechnical Reconnaissance of the 2016 ML6.6 Meinong Earthquake in Taiwan

On February 6, 2015, a local magnitude (M_L) 6.6 earthquake struck southern Taiwan, devastating the Tainan area. A field investigation was conducted by a survey team from the National Center for Research on Earthquake Engineering immediately after the earthquake. This paper summarizes the observed geotechnical damage features caused by the earthquake, including liquefaction, slope sliding, levee failure, and dam performance. Several liquefaction sites were observed despite the intensity of ground shaking being moderate (peak ground acceleration, ~0.2 g). Most of these sites were originally old ponds that were backfilled during different periods in the last three to eight decades. Two significant types of damage to the levee of the Tseng-wen River were observed. At the Jianshan site, a typical type of levee damage was observed, in which the level crest subsided and the side slope developed several cracks. At the Rixin site, a flow-type of failure caused tremendous loss of levee (~400 m in total) at three adjacent locations. The levee embankments had “flowed” up to 60 m into the river.