双层大跨桁架同步安装与多级卸载控制技术研究OA

Aiming at the problems of insufficient process coordination,lack of load distribution algorithms,and lagging green construction in the construction of double-layer large-span trusses,this paper takes the Western(Chongqing)Science Hall project as the engineering background and proposes a technical system of"integrated small-unit assembly-double-layer synchronous hoisting-graded intelligent unloading."Through high-precision prefabrication of small units in the factory(assembly error≤0.8 mm),combined with dual-crane coordinated lifting by crawler cranes and BIM simulation to optimize lifting point arrangement,synchronous installation of double-layer trusses is achieved(elevation and axis deviation≤3 mm).The design of"dual-purpose installation-unloading supports,"combined with ANSYS finite element simulation and dynamic stress monitoring(accuracy±1 MPa),establishes a graded unloading control process,ensuring an unloading height difference≤15 mm and stress variation rate≤10%.Engineering practice shows that this technology reduces the construction period by 30 days and costs by 22%(cumulative savings of 7.468 4 million yuan),with deformation control meeting specification requirements(maximum deflection value of 12 mm,displacement L/4 000).The research overcomes challenges such as large pre-assembly errors in irregular joints,high risks of high-altitude operations,and asymmetric load unloading,forming the"Double-Layer Large-Span Truss Synchronous Construction Method."It provides a feasible solution for industrialized,intelligent,and green construction of steel structure projects with spans of 50-80 m,demonstrating significant economic benefits and promotion value.