薄壁方钢管再生块体组合柱偏压承载力研究

Bias compression bearing capacity research of thin-walled square steel tube composite columns filled with demolished concrete lump

为分析有无肋、偏心距e、再生块体混合比η、长细比λ对薄壁方钢管再生块体组合柱偏压承载力的影响,对12根薄壁方钢管再生块体组合柱做偏压承载力试验,采用拟水平法分析各因素的影响程度。研究表明:长细比λ、偏心距e和混合比η综合效应对承载力影响高度显著,加劲肋对承载力影响显著;长细比λ由18.4增加到30.3,偏压承载力降低约450k N;偏心距e由25mm增加到50mm,有肋试件、无肋试件偏压承载力分别降低27.5,105k N;偏心距e为50mm、混合比η为35%时,长细比λ为18.4,30.3的试件加肋后承载力提高程度分别为21.38%,80%。对试验数据做线性回归分析,得出薄壁方钢管混凝土柱偏压承载力计算公式,计算精度较好。

To analyze the influences of stiffening rib, eccentricity e, demolished concrete lump mixing ratio η, slenderness ratio A on bias compression bearing capacity of thin-walled square steel tube composite columns filled with demolished concrete lump, bias compression bearing capacity test was conducted on 12 specimens, and quasi level method was used to analyze influence degree of various factors. The study shows that the effect of slenderness ratio A, eccentricity e and demolished concrete lump mixing ratio η＇s combined factor is highly significant on bearing capacity, and stiffener rib has significant effect on bearing capacity; when slenderness ratio A increases from 18.4 to 30. 3, bias compression bearing capacity reduces 450 kN; when eccentricity e increases from 25 mm to 50 ram, bias compression bearing capacity of stiffened specimens and non-stiffened specimens reduces 27.5 kN and 105 kN respectively; when eccentricity e is 50 mm and mixing ratio η is 35% , the improvement degree of bearing capacity of stiffened specimens with slenderness ratio A of 18.4 and 30. 3 is 21.38% and 80% respectively. Linear regression analysis on test data was conducted to obtain the bias compression bearing capacity formula of thin-walled square steel tube columns and the calculation accuracy is weft.