The bridge was the first major road crossing the Mekong River and linked Thailand’s Nong Khai province with the Lao capital, Vientiane. The bridge is 1170m long and 12.7m wide with two roadway lanes, two pedestrian paths and a railway line in the middle. The bridge construction consisted of a balanced cantilever with segmental match-cast precast concrete units which were post-tensioned together.
Madsen Giersing (MG) was appointed by John Holland to provide the detail design of the supporting frame required to temporarily support the bridge superstructure during construction.
The pier brackets were designed to resist the out-of-balance load generated by the installation of the precast concrete bridge segments either side of the bridge pier. During the construction the load in the beams and the bracket was closely monitored. This was compared with the theoretical loads to ensure that an overload of the support system did not occur.
In addition MG developed the erection procedure for the superstructure, including casting of the midspan joint, to ensure the loads on the support bracket were not exceeded.
John Holland Constructions