The expansion project of Jinan Yellow River Highway Bridge has brought good news. The project has completed the pouring of UHPC ultra-high performance concrete along the entire line, with a total pouring area of 27500 square meters.
It is reported that by using a new material UHPC and integrated paving equipment, the service life, corrosion resistance, crack resistance, compression resistance, and bending resistance of the steel bridge are further improved, the construction efficiency is increased by 30%, the number of workers is reduced by 50%, and the flatness is within 3mm.
The bridge deck structure of the main bridge and the cross embankment bridge in this project adopts the UHPC ultra-high performance lightweight composite steel bridge deck system, which consists of asphalt layer, adhesive layer, UHPC ultra-high performance concrete layer, and orthotropic steel bridge deck from top to bottom. The thickness of the UHPC ultra-high performance concrete layer is 50mm, with a single layer of HRB400 steel mesh arranged at a spacing of 10cm and a diameter of 10mm. The steel mesh is combined with the steel bridge deck to bear the same force, with a bulk density of about 28KN/m3, slightly larger than ordinary reinforced concrete.
UHPC is a special type of concrete with high flexural strength, toughness, durability, and erosion resistance. The compressive strength of UHPC currently used in the field of architectural design is greater than 120MPa, and the flexural strength is greater than 30MPa. After combining UHPC with steel bridge deck to form a lightweight composite bridge deck system, the stiffness of the bridge deck can be effectively increased by more than 40 times, the stress of the steel bridge deck can be significantly reduced, and the fatigue life of the bridge deck can be extended. It is expected to completely solve the two typical diseases of fatigue cracking and pavement damage of steel bridge decks.
The project introduces a new type of UHPC pavement integrated equipment for the construction of UHPC ultra-high performance concrete, integrating material distribution, vibration, leveling, finishing, and film coating, with significant construction advantages.
Using 3D laser to control elevation. Before construction, the bridge deck elevation measurement is summarized, and the sorted elevation and mileage data are input into the system. The laser receivers on both sides receive signals and transmit them to the controller to achieve automatic adjustment of the whole machine, precise control of elevation, and more convenient operation, which can achieve better leveling thickness and flatness.
