论文部分内容阅读
预应力电杆梢端产生纵裂的原因和防止措施已有不少报道,下面仅就我厂在这方面所取得的一点经验作一介绍,供同行参考。一、改变梢端混合料预应力电杆的生产一般是采用坍落度为4～6cm的混合料,其粗集料的最大粒径为20mm。我们改用分段配料,中下段采用工艺规程规定的混合料,梢端1米以内采用减小最大粒径的半干硬性混合料。 1、减小梢端粗集料粒径选用最大粒径不大于10mm的碎石作为梢端混合料的粗集料。减小梢端粗集料粒径,可以增大石子与水泥石的啮合面,减少砼分层,缩小水膜层,以提高砼的强度和抗裂度。
There have been many reports on the reasons for the occurrence of longitudinal cracks in the tip of prestressed electric poles and preventive measures. The following is only an introduction to our factory’s experience in this area for reference by peers. First, to change the production of pre-stressed poles of the tip mixture The slump of 4 to 6 cm is generally used, and the maximum particle size of the coarse aggregate is 20 mm. We use subsection ingredients, and the middle and lower sections adopt the mixture specified in the process specification, and the semi-dry hard mixture that reduces the maximum particle size is used within one meter of the tip. 1. Decrease the diameter of the tip coarse aggregate The coarse aggregate with a maximum particle size of no more than 10 mm is used as the tip mix. Decreasing the diameter of the coarse aggregate at the tip can increase the meshing surface between the gravel and the cement stone, reduce strontium delamination, and shrink the water film layer to increase the strength and crack resistance of the crucible.