钢绞线锈蚀产物填充及裂缝宽度预测

针对钢绞线锈蚀导致混凝土开裂的现象，通过试验研究钢绞线锈蚀产物在裂缝中的填充及锈胀裂缝的开裂情况，分析箍筋对锈蚀产物填充及混凝土开裂的抑制作用.考虑锈蚀产物填充比例和钢绞线捻制形状等因素，建立锈胀裂缝宽度预测模型，基于试验结果对该模型进行验证.研究表明，锈胀裂缝开裂角的正切值随锈蚀率的增加而增大，箍筋能够有效限制裂缝扩展和铁锈填充.锈蚀产物的填充随裂缝宽度的增加而变化，裂缝宽度达到临界值前，铁锈填充深度随裂缝宽度的增长而增大；裂缝宽度超过临界值后，铁锈填充深度基本保持为常值.建立的模型能够有效地预测锈胀裂缝宽度，合理地考虑铁锈填充可以提高预测模型的精度.
Abstract: An experimental study was designed to analyze the filling extent of strand corrosion products in the cracks and the angle of concrete cracking aiming at the problem that strand corrosion would induce the concrete cracking. The restraint effect of stirrups on filling of corrosion products and concrete cracking was analyzed. A prediction model of crack width was proposed considering the filling extent of corrosion products and the twisting shape of strand. The model was verified by the experimental results. Results show that the tangent of cracking angle increases with increasing corrosion loss. Stirrups can significantly restrain the crack propagation and the filling of corrosion products. The filling extent of corrosion products varies with the increase of crack width. The filling extent of corrosion products increases with increasing crack width before the crack width reaches the critical value. The filling extent of corrosion products maintains as the constant after the crack width reaches the critical value. The prediction model can effectively predict the corrosion-induced crack width. The filling of corrosion products should be reasonably considered to improve the precision of the model.