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一、前言 索道承载索设计可归纳出如下四个约束条件: 1.破断的强度条件。 设破断力为T_(pd),安全系数为k,最大工作张力为T_(max),则要求T_(pd)≥k T_(max) (1) 2.耐久性条件。 在文献中以轮压R与张力T之比作为指标,指出:在一般索道设计上习惯采用R/T=1/80～1/100,虽然采用如此小的R/T值是理想的,但对林业索道来说是不经济的。根据许多林业索道的调查结果来看,采取小于R/T=1/30～1/40还可以保证正常运行。如超过R/T=1/20时,虽然对其他条件有利,但承载索的损耗还是特别显著。因而建议对林业索道采用下列数值:R/T≤1/30～1/50。根据我国实际情况,文献建议:R/T=1/m=1/20～1/50,即m=20～50,可称为耐久性参数。
First, the preface ropeway cable design can be summarized as the following four constraints: 1. Broken strength conditions. Assuming that the breaking force is T pd, the safety factor is k, and the maximum working tension is T max, then T pd ≥ k T max. (1) 2. Durability conditions. In the literature, the ratio of wheel pressure R to tension T is taken as an index. It is pointed out that R / T = 1/80 to 1/100 is generally adopted in the design of a typical cableway. Although it is desirable to use such a small R / T value, It is not economical for forestry cableway. According to many forestry cable survey results, take less than R / T = 1/30 ~ 1/40 can also ensure normal operation. If R / T = 1/20 is exceeded, the loss of the carrier cable is particularly significant, although it is favorable for other conditions. Therefore, it is suggested that the following values be used for forestry ropeway: R / T≤1 / 30 ~ 1/50. According to China’s actual situation, the literature suggests: R / T = 1 / m = 1/20 ~ 1/50, that is, m = 20 ~ 50, which can be called the durability parameter.