Numerical Simulation Of The Lifting Process Of Steel Structures Under Uneven Settlemen

The construction industry in our country is undergoing rapid development,accompanied by significant improvements in people’s living environment.However,this progress has also exposed an increasing number of issues related to the quality of construction projects.Each year,a considerable number of buildings in our country experience problems such as cracking,tilting,and settling,which not only disrupt the normal lives of residents but also pose significant safety risks.Consequently,tilt correction technology has emerged as a vital component in the field of structural reinforcement.Among various tilt correction techniques,jacking correction stands out as a method that utilizes lightweight and small-scale lifting equipment to rectify tilted buildings.This technology effectively addresses spatial height and overall tilt rate irregularities while ensuring the safety and integrity of the building’s main structure.Extensive research indicates that jacking correction technology yields considerable economic benefits,requiring minimal manpower and material resources,while swiftly restoring the building’s normal functionality.It is particularly well-suited for buildings with shallow foundations and light loads on the upper structure,proving highly effective in addressing tilt issues resulting from non-linear and uneven settlement.The thesis describes a case study of a primary school’s light steel structure building,where the uneven settlement of the foundation resulted in the tilting of the main structure.It begins by analyzing the causes of uneven settlement and provides a detailed correction plan.Subsequently,using Abaqus finite element numerical simulation analysis,the study investigates the stages of uneven settlement,column-breaking,and jacking,yielding the following research findings and achievements:(1)Analyze the reasons for the uneven settlement of the building,propose a columnbreaking jacking correction scheme,and complete the correction work according to the correction scheme.(2)Carry out fine finite element modeling and analysis of the building,use fine material constitutive models,use fine damage mechanics models for both concrete and steel,and carry out fine finite element modeling of the structural details to examine the structural damage after settlement and jacking,thereby achieving the purpose of guiding actual engineering.(3)Through the perturbation analysis module of the ABAQUS numerical simulation software,it is found that uneven settlement causes significant changes in the structural eigenvalues and frequencies,thereby having a significant impact on the characteristics of the structure and the perturbation response.Compared to before the settlement,the structure is more sensitive to external load disturbances.In addition,uneven settlement causes the material at some nodes of the structure to enter the yield stage,and a large additional stress is generated at the column base.(4)During the column-breaking and jacking process,a comparative study of the two construction methods of "alternating column-breaking" and "simultaneous column-breaking" was conducted,and it was concluded that the "alternating column-breaking" method has obvious advantages in terms of stress field disturbance and structural stability.Comparing the "proportional jacking" and "segmented jacking" jacking processes,research from the perspective of stress disturbance and energy dissipation found that the differences between the two jacking methods are small,and the "segmented jacking" method is slightly superior.