Experimental Study on the Damage of Bridge Pier under the Impact of Rockfall

Table 6

The number of grids of spalled concrete at the impact position.

Specimen	The initial falling height (relative height) of the pendulum ball (m)
	1	2	3	4
S4.1	1	4	17	44
S8.3	1	3	17	43
S2.1	1	4	21	37