Zhao Zhouqiao, Hebei, Lugou Bridge, Guangdong Guangji Bridge, etc. Zhao Zhouqiao in Hebei, Lugou Bridge in Beijing and Guangji Bridge in Chaozhou, Guangdong are all Beili Bridges. Double force bridge is to connect the cross beam and the longitudinal beam, and finally lock the longitudinal beams on both sides with four measuring beams, so that the stress of the whole bridge can be evenly shared. The greater the stress in front, the closer the various parts of the bridge are combined.