"落地式大摆钟" can be translated as "floor-standing grandfather clock" or simply "grandfather clock" in English.
"Floor-standing" emphasizes that it is a free-standing clock placed on the floor.
"Grandfather clock" is a common and widely recognized term for a tall, free-standing clock with a pendulum and a large face, typically found in living rooms or hallways.
In most contexts, just saying "grandfather clock" would be sufficient and clear.