无机胶复合竹-混凝土组合连接件的顺纹抗剪承载性能

Parallel-to-Grain Shear Performance of InorgBam-Concrete Composite Connections

摘要:

提出一种基于植筋连接的剪力键形式，用于无机胶复合竹（InorgBam）与混凝土组合梁的界面连接，并通过推出试验，研究了螺杆直径和扩孔注胶工艺对连接件顺纹抗剪性能的影响，重点分析了荷载-滑移响应、破坏模式、顺纹抗剪承载力、滑移刚度和延性等关键性能指标；基于试验和理论分析，提出了无机胶复合竹-混凝土组合连接件顺纹抗剪承载力计算模型。结果表明：无机胶复合竹-混凝土组合连接件在顺纹抗剪承载力、滑移刚度和延性等方面均优于传统木-混凝土连接件；增大螺杆直径可有效提高连接件的顺纹抗剪承载力，发生弯曲破坏的试件中，随着螺杆直径的增加，试件的滑移刚度逐渐提高；扩孔注胶有效增强了螺杆的侧向约束，延缓了无机胶复合竹孔壁的压溃，可显著提高连接件的顺纹抗剪承载力和初始刚度，但由于注胶层呈现脆性破坏特征，导致试件延性下降。

Abstract:

A novel shear connector form based on rebar planting connection was proposed for the interfacial bonding of composite beams composed of inorganic-bonded bamboo composite（InorgBam） and concrete. The effects of threaded rod diameter and process of hole expansion and glue injection on the parallel-to-grain shear performance of InorgBam-concrete composite connections were investigated. The key performance indicators such as load-slip response， failure mode， parallel-to-grain shear capacity， slip stiffness， and ductility were analyzed emphatically. Based on experiments and theoretical analysis， a calculation model for the parallel-to-grain shear capacity of InorgBam-concrete composite connections was proposed. The results show that compared to the traditional timber-concrete connections， the InorgBam-concrete composite connections exhibit superior parallel-to-grain shear capacity， slip stiffness， and ductility. Increasing the threaded rod diameter can effectively improve the parallel-to-grain shear capacity of the connections. For the specimens that failed in bending， the slip stiffness increases gradually with the enlargement of threaded rod diameter. The hole expansion and glue injection process can effectively enhance lateral restraint on the threaded rod， delays crushing failure of the InorgBam hole wall， and significantly improve both parallel-to-grain the shear capacity and initial slip stiffness of the connections. However， due to the brittle nature of the grouted adhesive layer， the ductility of the connections is reduced.