季冻区回收胎圈钢丝网(RSFW)增强T型深梁抗剪承载力性能研究

Study on shear capacity of T-section deep beam strengthened by recycled bead steel mesh(RSFW)in seasonal freezing area

采用三点弯加载方法对5榀T型深梁进行试验,选用新型数字图像相关(Digital Image Correlation.DIC)技术监测梁表面应变场;对比研究经冻融循环后粘贴回收胎圈钢丝加固网前后T型深梁的抗剪性能。回收胎圈取自废旧轮胎中,是一种轻质高强、防腐蚀,可回收的绿色环保材料,使用回收胎圈作为加固材料可以有效地缓解废旧轮胎对环境的影响。结果表明:5榀试验梁均发生斜压破坏,T型深梁在加固后的斜裂缝开裂荷载及抗剪承载力都比加固前有显著提高,斜裂缝开展速度较加固前减缓,揭示了回收胎圈钢丝加固混凝土T型深梁后抗剪性能变化规律,表明粘贴回收胎圈钢丝网能有效抑制该试验梁的抗剪破坏。该试验研究成果能够为工程中实际应用回收胎圈钢丝网加固混凝土T型深梁抗剪性能提供技术参考。

In this paper,five T-section deep beams are tested by three-point bending loading method,and a new Digital Image Correlation(DIC)technology is selected to monitor the surface strain field of the beam;The shear properties of T-section deep beams before and after freezing and thawing cycle are compared and studied.Recycled tire beads are taken from waste tires.They are light,high-strength,anti-corrosion and recyclable green environmental protection materials.Using recycled tire beads as reinforcement materials can effectively alleviate the impact of waste tires on the environment.The results show that the oblique compression failure dominated by shear failure occurs in all 5 test beams,and the oblique cracking load and shear bearing capacity of T-section deep beams after reinforcement are significantly higher than those before reinforcement;After strengthening,the development speed of oblique cracks in the test beam slows down,and the strain in the area between the loading point on the beam surface and the fabrication line decreases.The change law of shear performance of concrete T-section deep beam strengthened with recycled bead steel wire is revealed,which shows that the reinforcement method can effectively restrain the shear failure of the test beam;The research results can provide technical reference for recycling bead steel wire mesh to shear strengthen concrete T-section deep beam in engineering practice.