深圳大学学报理工版

有机锚固胶与旧混凝土具有较高的黏结强度,但是两者的界面相容性较差. 而且有机锚固胶不耐高温,因此不能用于高温环境下的工程加固. 为了克服有机锚固胶存在的问题,对磷酸盐水泥(magnesium phosphate cement, MPC)进行改性,使其成为一种新型锚固胶. 制备了工作性能适宜锚固要求的MPC砂浆,通过钢筋拔出实验研究锚固深度对磷酸盐水泥砂浆胶锚固性能的影响,根据植筋锚固施工工艺和拉拔技术要求在现场对MPC砂浆进行了植筋实验.研究表明,临界锚固深度为钢筋直径的17.5倍时,在临界锚固深度范围内,拉拔力与锚固深度为非线性函数关系; 大于临界锚固深度时,拉拔力不再增长.现场实验中带肋钢筋达到屈服,体现了MPC砂浆优良的植筋锚固性能.

Organic anchoring adhesives have high binding strength with the concrete substrate, but poor interfacial compatibility. They cannot be used in structure reinforcement in high temperature environments due to poor high temperature resistance. In order to overcome the problems of organic binders, we modify the magnesium phosphate cement(MPC)to obtain a new type of anchoring adhesive by studying the effect of anchoring depth on the anchorage performance of MPC mortar. We test the anchoring effect of MPC mortar in the field according to both construction and drawing technology. The results show that the critical anchorage depth of steel bars in MPC mortar is 17.5 times the diameter of steel bars. In the range of critical anchorage depth, the relationship between the pulling force and the depth of anchorage is nonlinear. When anchor depth is larger than the critical value, the pulling force will no longer grow. In the field experiment, the ribbed steel bar is yielded, which embodies the excellent anchoring performance of MPC mortar.

引言
1 实验
2 实验结果与讨论
3 结论

图1 构件上钻孔位置示意图<br/>Fig.1 Hole locations on the component

图1 构件上钻孔位置示意图
Fig.1 Hole locations on the component

表1 钻孔深度及钢筋直径<br/>Table 1 Drilling depth and bar diameter for each hole

表1 钻孔深度及钢筋直径
Table 1 Drilling depth and bar diameter for each hole

图2 拉拔力随锚固深度的变化趋势<br/>Fig.2 The relationship between the pulling force and the depth of anchorage

图2 拉拔力随锚固深度的变化趋势
Fig.2 The relationship between the pulling force and the depth of anchorage

图3 线性拟合结果
Fig.3 Linear fit results

表2 线性拟合结果对比<br/>Table 2 Comparison of linear fitting results

表2 线性拟合结果对比
Table 2 Comparison of linear fitting results

图4 多项式拟合结果<br/>Fig.4 Polynomial fitting results

图4 多项式拟合结果
Fig.4 Polynomial fitting results

表3 多项式回归结果<br/>Table 3 Comparison of polynomial fitting results

表3 多项式回归结果
Table 3 Comparison of polynomial fitting results

图5 非线性曲线拟合结果<br/>Fig.5 Nonlinear curve fitting results

图5 非线性曲线拟合结果
Fig.5 Nonlinear curve fitting results

表4 非线性曲线拟合结果对比<br/>Table 4 Comparison of non-linear curve fitting results

表4 非线性曲线拟合结果对比
Table 4 Comparison of non-linear curve fitting results

表5 现场拉拔试验结果<br/>Table 5 Results of the field pull-out test

表5 现场拉拔试验结果
Table 5 Results of the field pull-out test

表6 钢筋拉应力与剪应力值<br/>Table 6 The tensile stress and shear stress values

表6 钢筋拉应力与剪应力值
Table 6 The tensile stress and shear stress values

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备注

引言

1 实验

2 实验结果与讨论

3 结论

期刊信息

备注

引言

1 实 验

2 实验结果与讨论

3 结 论

期刊信息

1 实验

3 结论