抗浮锚杆布置方式的数值分析

Numerical Analysis Study of Anti-floating Anchor Layout Styles

总结了现有抗浮锚杆的布置形式及其优缺点,根据板底结构的传力模式和弹塑性变形理论,提出了面状非均布方案,即沿底板塑性铰线周边和地梁跨中布设锚杆。结合工程实例,采用三维数值模拟分别对预应力面状非均布、预应力面状均布、非预应力面状非均布和非预应力面状均布,四种锚杆布置方式下的底板板顶位移、地梁和底板应力、锚杆轴力进行了对比分析。通过分析认为,当锚杆为预应力面状非均布时,底板、地梁变形小且规则,地梁内力小,各锚杆轴力分布均匀,有利于抗浮锚杆地统一配置,从而使地下室抗浮更安全、更经济。

This paper summarized the existing anti-floating anchor layout styles and it compared their advanta- ges and disadvantages. According to the force-transmitting mode of bottom plate and the theory of elastic-plas- tic deformation, it proposed the un-uniformly distributing in plane scheme, which deploys anchors around the yield line of bottom plate and at mid-span of ground beam. Based on project practices and 3D numerical simu- lations, this paper made comparative analyses of the top of bottom plate displacement, ground beam and bot- tom plate stress, anchor axial force under four different anchor layout styles： prestress un-uniformly distribu- ting in plane, prestress uniformly distributing in plane, un-uniformly distributing in plane, and uniformly dis- tributing in plane. Through analyses, it is concluded that when anchors are prestress un-uniformly distributed in plane, the bottom plate deformation and ground beam deform is little and regular and ground beam internal force is small. Additionally, the axial force of each anchor bolt is well distributed, which is beneficial to dis- tribute anti-floating anchors unified to ensure the anti-floating basement safer and more economical.