基于ADINA的河套灌区预制混凝土渠道保温防冻胀效果数值模拟

Numerical simulation of thermal insulation and frost heave effect of precast concrete channel in Hetao Irrigation District based on ADINA

近年来,内蒙古河套灌区在渠道防冻胀方面取得了大量试验研究成果,但采用有限元模型模拟渠道保温防冻胀效果目前还没有相关研究,特别是对于河套灌区预制混凝土渠道适宜的保温模式目前还没有相关报道。文中在原位渠道试验的基础上依托ADINA软件建立了有限元渠道模型,对铺设不同厚度聚苯板渠道温度场和冻胀量进行了模拟,提出了预制混凝土渠道适宜保温模式。研究得出,预制混凝土渠道各处理渠段均阴坡温度梯度>渠底温度梯度>阳坡温度梯度,并且随着保温板铺设厚度的增加,阴坡和阳坡渠基地温的温度梯度逐渐减小,渠基最大冻胀部位位于渠道下坡1/5~1/3处;铺设6~12cm以上聚苯板对渠基冻量减小幅度最为明显,将最大冻胀量控制在3cm以内;河套灌区6cm预制混凝土板衬砌渠道适宜铺设的聚苯板厚度为6~8cm。

In recent years,it has achieved great experimental research results in preventing frost heave of channels in Hetao Irrigation District,Inner Mongolia,but there is currently no relevant research on using finite element models to simulate the effect of thermal insulation and anti-frost heave of channels.Especially,there is no relevant report on the appropriate thermal insulation mode for prefabricated concrete channels in Hetao Irrigation District.Based on in-situ channel tests and ADINA software,this study established a finite element channel model to simulate the temperature field and frost heave of channels laid with different thicknesses of polystyrene board,and proposed a suitable thermal insulation mode for prefabricated concrete channels.The research shows that the temperature gradient of each treated section of the prefabricated concrete channel is of the shady slope>the temperature gradient of the channel bottom>the temperature gradient of the sunny slope.With the increase of the thickness of the insulation board,the temperature gradient of the ground temperature of the shady slope and the sunny slope channel foundation gradually decreases,and the maximum frost heaving position of the channel foundation is located at 1/5~1/3 of the downstream slope of the channel.The laying of polystyrene boards with a thickness of 6 to 12cm or more has the most significant reduction in the frost heave of the canal foundation,and the maximum frost heave is controlled within 3cm.The suitable thickness of polystyrene board for laying 6cm prefabricated concrete slab lined channels in Hetao Irrigation District is 6~8cm.