Investigation on Seismic Damage Model Test of a High Concrete Gravity Dam Based on Application of FBG Strain Sensor

Table 8

Model crack responses during the testing.

Load case	Observations
1#SW1	No visible crack
1#SW2	No visible crack
1#SW3	No visible crack
1#SW4	No visible crack
1#SW5	The first crack appears at downstream surface of neck of model, the crack length is about 5cm.
1#SW6	The upstream surface of model is cracked, and the main crack at downstream extends to center of model section.
1#SW7	At the downstream surface, the second small crack appears at 20cm below the model crest, and the main crack expands from moderate to severe cracks.
1#SW8	At the downstream surface, a crack appears at 70cm below the model crest (Dam waist), and the main crack runs through the model, and a small crack appears above the second crack. Severe damage area is formed in the neck of the model, shown in Figures 14(a), 14(c), and 14(d).