Investigation of both the flexural and shear bond performance of the polyurethane-mortar interface under micro and macro scale
Investigation of both the flexural and shear bond performance of the polyurethane-mortar interface under micro and macro scale
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研究微观和宏观尺度下聚氨酯-砂浆界面的弯曲和剪切粘合性能
DOI：
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发表时间：
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影响因子：
3.2
通讯作者：
Tianbao Huang
中科院分区：
文献类型：
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作者：
Wenbo Ma;Cong Hu;Shuaicheng Guo;Zenggang Zhao;Tianbao Huang
聚氨酯材料在胶凝材料的修补中得到了广泛的应用，其修补效率很大程度上取决于聚氨酯材料与水泥基之间的粘结强度。本文旨在评价不同含水量和改性剂含量的水泥砂浆与聚氨酯之间的剪切和弯曲粘结强度。采用斜剪试验和三点弯曲试验对聚氨酯界面砂浆试样的抗剪和抗弯强度进行了测试。首先考察了聚氨酯/水比对粘结强度的影响，当聚氨酯/水比为30%时，试件的剪切和弯曲粘结强度均达到最高。为了进一步提高粘接强度，在聚氨酯中进一步添加了乙烯-醋酸乙烯酯（EVA），并进一步考察了取代率对粘接强度的影响。宏观强度试验表明，添加10% EVA的聚氨酯样品强度最高。利用扫描电子显微镜（SEM）和原子力显微镜（AFM）进一步研究了水分和EVA含量对其影响的机理。研究了水分和EVA含量对粘接强度的影响，为聚氨酯材料的现场应用提供了有益的信息。
Polyurethane materials have been widely applied in the mending of cementitious materials, and the mending efficiency is highly impacted by the bond strength between polyurethane materials and cement base. This paper aims to evaluate both the shear and flexural bond strength between cement mortar and the polyurethane with different water and modifier content. The shear and flexural bond strength were examined with the slant shear test and three-point bending test on mortar samples prepared with polyurethane interface. The influence of polyurethane/water ratio on the bond strength was first examined, and both the highest shear and flexural bond strength was achieved for the samples with 30% polyurethane/water ratio. To further enhance the bond strength, the Ethylene-vinyl acetate (EVA) was further added to polyurethane, and the influence of replacement ratio on the bond strength was further examined. The macro-size strength tests indicated the highest strength was achieved for the polyurethane samples with 10% replaced EVA. The mechanism behind the influence of water and EVA content was further examined with scanning electron microscope (SEM) and atomic force microscope (AFM). The examined relationship between water and EVA content on the bond strength can provide useful information for the field application of the polyurethane materials.