防渗渠道输水损失的估算

Estimating Seepage Loss of Lined Canal

渠道防渗已成为我国大型灌区改造的主要手段 ,以提高水资源的利用率 ;如何估算防渗渠道的水量损失 ,已成为评价灌区改造的重要技术问题。在概括渠道输水损失的各种估算理论和方法的基础上 ,揭示了流量指数型估计式 σ=A/ Qm(% )对于防渗和非防渗渠道都具有广泛的适用性。并基于全国范围内的实测资料统计分析 ,对影响估计式参数的因素及规律性进行了深入分析 ,建议对防渗或非防渗渠道的渠道渗漏损失均采用该估计式 ,防渗渠道的参数可通过现场静水试验求得 ,或直接对透水性系数进行折减。

Lining soil canal now is the main measure for enhancing water resources use efficiency in rehabilitation of large scale irrigation areas in China. How to reckon the seepage losses of lined canals has become a significant professional problem in rehabilitation evaluation. Based on an analysis of existing theories and methods of estimating irrigation canal seepage losses, it is revealed that σ=A/Q m (%) is a widely applicable model whether for lined or non lined canal. According to the statistical analysis results of on site data measured nationwide,factors affected the parameters of the model and their changes are analyzed and discussed. It is suggested that seepage losses of both lined canals and non lined canals should be calculated with the model. The relevant parameters in the model may be determined with on site static water measurement method, or deduced directly from permeability coefficient.