多规范视阈下扣件式钢管支撑体系稳定承载力数值模拟分析

Numerical Simulation Analysis of Bearing Capacity of Fastener-type Steel Pipe Support System under Multi-specification

目的 研究多个相关规范关于模架支撑体系的构造差异,分析不同构造形式对扣件式钢管支撑体系的力学性能影响,为架体优化设计和工程应用提供借鉴。方法 基于ANSYS有限元分析软件,建立有限元模型进行数值模拟,通过改变支撑体系扫地杆的位置、横杆步距、立杆纵横向间距、自由端长度、架体高宽比及剪刀撑布设等构造参数,对比不同构造形式的支撑体系稳定承载力数值和杆件内力分布,研究相关构造因素对架体安全性的影响。结果 构造形式对扣件式钢管支撑体系的稳定承载力及位移变形的影响显著;依照不同规范的设计方法,相同的支撑体系力学计算结果差异明显。结论 扫地杆高度在0.4 m以下、步距1.8 m以内、纵横向立杆间距1.5 m以下、自由端高度0.8 m以下、高宽比不超过2或者增强剪刀撑布设能有效提高支撑体系的稳定承载力和安全性;在支撑体系荷载标准值确定、荷载组合方式选取及立杆稳定性验算方面宜优先选用《建筑施工模板安全技术规范》(JGJ162-2008)和《建筑施工扣件式钢管脚手架安全技术规范》(JGJ130-2011)执行;扫地杆、横杆步距、立杆自由端长度和剪刀撑布设以《建筑施工扣件式钢管脚手架安全技术规范》(JGJ130-2011)为宜;对于超过8m的高支模,《建筑施工脚手架安全技术统一标准》(GB51210-2016)的安全储备更高。

The paper is proposed to study the differences of multiple relevant codes for comparative analysis of safety,the influence of different structural factors on the mechanical properties of the fastener-type steel pipe support system under multiple codes,and to draw some conclusions and suggestions that are beneficial to engineering practice.By changing the height of the sweeping pole,the step distance,the vertical and horizontal pole spacing,the height of the free end,the aspect ratio and the related structural factors of the scissor support layout of the support system,a number of different finite element models for numerical simulation were established based on ANSYS by comparing the differences of several relevant specifications and the calculation indicators and studied the influence of the relevant structural factors of the support system on the safety.The result showed that different structural factors have obvious effects on the stable bearing capacity and displacement of the fastener-type steel pipe support system,and the calculation results of the same support system under different specifications are significantly different.It can be concluded that in engineering practice,the height of the sweeping pole is less than 0.4 m,the step distance is less than 1.8 m,the vertical and horizontal pole spacing is less than 1.5 m,the height of the free end is less than 0.8 m,the aspect ratio is not more than 2,or the enhanced scissor bracing can effectively improve.Support system security.JGJ162 and JGJ130 should be preferred for the design of support system load,combination selection and stability check calculation of uprights.The sweeping rod,step distance,free end and scissor support are preferably set up with reference to the JGJ130.For high formwork over 8 meters,it tends to be safer and more reliable when in accordance with the requirements of the GB51210.