宁夏引黄灌区混凝土衬砌渠道的冻害原因及对策

Reasons and Countermeasure for Freeze Damage to the Cement Lined Canal in Yellow River Irrigation Area in Ningxia

混凝土衬砌是北方灌区沟渠普遍采用的一种渠道防渗衬砌形式 ,可以有效地减少渠道渗漏损失 ,提高水资源的利用率 .由于受环境、气候等多种因素影响 ,渠道混凝土衬砌冻胀破坏情况较为严重 ,其中水、土和温度是引起冻胀产生的主要原因 .根据对宁夏引黄灌区混凝土衬砌渠道的普遍调查 ,针对渠道混凝土衬砌产生冻胀破坏的原因和规律 ,从自然条件和工程条件方面进行了综合分析 ,并就如何预防和减少冻胀现象的产生 。

Cement lined canals are a method of seep ag e-resistance which are universally used in the Northern Irrigation Area. It may efficiently reduce the seepage loss from canals, thus improving the utilization ratio for water resources. Due to factors such as climate and environment, exfo liation and the resulting damage of cement lined canals has become more serious. Water, soil and temperature are the main natural causes that lead to exfoliatio n. Based on the investigation of the cement lined canal in Ningxia Yellow River Irrigation Area, this paper carried out a systematic analysis from two aspects ( natural and engineering conditions) in accordance with the causes of exfoliation and its regularity. Finally, in order to deal with prevention and reduction of phenomena such as exfoliation, this paper raised some specific provention measur es and suggestions from different aspects including canal programme design and construction course.