Restoration of seismically-vulnerable historical masonry structures struck by an earthquake ()Microtremor measurement of Layer Tower Buildings 2

摘要

The Natural frequency for the 2009 measurement, first mode,rnhas a difference of 0.07 Hz, with the 2017 measurment for the 2ndrnand 3rd mode the difference increases. Before the Ghorka 2015rnEarthquake, the largest amplitude seems to be at the second floorrnand fourth floor for the third mode. Despite the malfunction forrnthe 2017 NS direction vibration mode the values below the toprnseems to follow a common behavior for this type of building. Therndifference in frequency between NS and EW on each year, mayrnindicate that the structure is not symmetric.