Numerical Simulation On The Analysis Of The Effect Of Bottom Frame Structure's Stiffness On Foundation's Uneven Settlement

Uneven settlement of the building closely related to security is one of the important reasons that lead to engineering accident. And also an uneven settlement could cause the inclination and deformation of buildings, seriouslly leading to cracking or even damage. Due to the integrity and stiffness of bottom frame structure house is relatively weak, so this structure form is more sensitive to the settlement. To meet the housing needs of the people at this stage, this structure form has been widespread in the size of the city. So how to reduce or avoid the risks of uneven settlement of bottom frame structure housing and restore normal service condition is a valuable subject.Firstly, the form of uneven settlement destruction will be introduced, and it is considered that different settlement results in different fracture morphology. And then harm caused by uneven settlement will be analized, the main reasons and accident prevention methods to uneven settlement will be concluded, and then processing methods will be put forward.Secondly, the selection of material model, material parameters, the constitutive curve of the material, non-linear convergence criteria, the meshing principle and so on will be explored and studied. The nature of the three units used in this numerical simulation will be introduced.Thirdly, this thesis emphasizes to set up models of the masonry structure with bottom frame, which based on the finite element analysis software ANSYS. Influences of changes in bottom floor of column size and wall holes filled between bottom columns on uneven settlement will be analyzed, both considered the central sink and ends sink. The analysis showed that increase column size can reduce the uneven foundation settlement in the two sinks, and at the same time compared with increase all column size only increase the small settlement column size can have better effect. Also fill the holes can reduce the uneven foundation settlement in the two sinks. While the central sink bigger filled the sides holls can have better effect, when the ends sink bigger filled the whole holls can have better effect.Lastly, a case of a bottom frame structure of central sink bigger uneven settlement will be introduced. According to the surveys and processing of the data, we will analyze the causes of the accident and introduce the reinforcement processing method and strengthen the rigidity of the bottom frame structure part in the incident reinforcement works will be described in detail which provides an experience when deal with similar accidents.