At present, piles with circular are used in all casting bore-hole pile foundations, but these piles have smaller perimeter and smaller section modulus as compare with the rectangular ones;

目前钻孔灌注桩基中的桩均为园形截面，和矩形截面的桩相比，园桩的周长、断面系数较小，抗弯能力差。

youdao

Authorities said then that eight masked, heavily armed men in clothing resembling police uniforms had burst through a hole in the perimeter fence onto the airport tarmac in two vehicles.

CNN: 33 arrests in Belgium diamond heist

Without firing a shot, they stole 120 packages of diamonds that had just been loaded into the hold of a Fokker-100 regional jet bound for Zurich, then escaped back through a hole cut in the perimeter fence.

WSJ: Police Detain Suspects in Brussels Airport Diamond Heist