论文部分内容阅读
针对离心法生产的环形钢管混凝土桩,外径Ф400、内径Ф220,钢管厚度6mm,钢管材料Q235B,混凝土强度等级C80,运用试验和理论分析方法研究其弯曲性能.试验表明,钢管与混凝土端部界面无滑移,协同工作性能良好,弹性极限弯矩290kNm,相应的挠跨比1/450;塑性极限弯矩394kNm,相应的挠跨比1/100;在挠度达到跨度的1/30时,弯矩-挠度曲线仍然处于上升阶段,最大试验弯矩430kNm,相应的延性系数15.运用材料力学原理,忽略两种材料界面间的粘结滑移,认定受拉区混凝土开裂退出工作,推导建立其塑性抗弯承载力计算方法,计算值与试验值基本吻合.研究表明,环形钢管混凝土桩具有很高的抗弯承载力和优越的弯曲延性,具有良好的抗震性能.
The circular concrete-filled steel tubular piles produced by the centrifugal method are characterized by test and theoretical analysis with the outer diameter of Ф400, the inner diameter of Ф220, the thickness of the steel pipe of 6mm, the material of the steel pipe Q235B, and the strength of the concrete C80. The tests show that the steel pipe- No slip, and good cooperative performance. The ultimate bending moment is 290kNm, and the corresponding ratio of bending to span is 1/450. The plastic ultimate bending moment is 394kNm, and the corresponding ratio of bending to span is 1/100. When the deflection reaches 1/30 of the span, Moment-deflection curves are still in the ascending stage, the maximum test bending moment 430kNm, the corresponding ductility coefficient 15. Using the principle of mechanics of materials, ignoring the bond slip between the two materials interface, identified as tension zone concrete cracking exit work, derived its establishment The calculation method of plastic flexural capacity is in good agreement with the experimental data.The results show that the circular CFST has high flexural capacity and excellent bending ductility and good seismic performance.