渠道保温板的优化及抗冻胀辅助设计软件的研究

发布时间：2018-06-29 00:47

本文选题：渠道抗冻胀 + 辅助软件　；参考：《西北农林科技大学》2014年硕士论文

【摘要】：在我国北方地区当冬季气温降到零度以下时，负气温对土建工程有一定的破坏作用，对渠道防渗工程的破坏尤为严重。衬砌渠道工程发生冻胀破坏问题后，，降低了渠系工程的输水效率，造成水资源的严重浪费。因此，防治这些地区的渠道冻胀破坏成为了一个亟待解决的工程问题。准确进行渠道抗冻胀计算，拟用合适的防冻胀措施，是研究渠道冻胀的重点方向。以往的渠道抗冻胀设计以参阅规范的人工手算为主，计算量大，计算过程中选用参数多，部分参数需查图、查表获得；查图查表过程单调繁琐且随机性高偶然误差大。因此考虑开发辅助设计软件来替代这些重复、繁杂的工作，从而提高渠道抗冻胀设计的效率和准确性。在防冻胀措施方面，一些地区的渠段虽利用聚苯乙烯保温板来防冻胀破坏,但具体的铺设厚度一般是根据有关规范，直接计算出保温板的厚度，这样计算出的结果往往不是最经济最合理的，因此需要对其铺设厚度进行优化。针对混凝土衬砌渠道冻胀破坏，本文论述了国内外在关于渠道冻胀方面的研究进展；总结了目前在渠道上广泛使用的防冻胀工程措施，并且着重做了以下的研究工作: （1）以甘肃靖会渠道为原型渠道，将渠基土和衬砌体视为整体结构，按照各向同性冻土介质并结合有限元分析软件ABAQUS，对铺设了不同厚度的保温板的衬砌渠道进行热、应力直接耦合分析计算，得出在采取不同保温措施条件下，渠道的温度场和位移场的分布规律。通过对比分析，得出最优保温板厚度阴阳坡为8cm，渠底为3cm。（2）本文模型拟用考虑渠道阴阳坡不同遮阴程度的情况下，由冻结期内各月的平均气温推导得到渠道各个部位的表面温度值。对缺乏渠道各个部位的表面温度实测值的模拟模型有一定的借鉴意义。通过实验结果和计算机模拟结果对比分析，渠道的温度场、设计冻深、应力场的分布规律基本一致，说明本文提出的数值模拟方法是合理可行的。（3）依据SL23—2006《渠系工程抗冻胀设计规范》，基于C++编程开发了衬砌渠道抗冻胀辅助设计软件。软件对计算过程进行可视化，能访问Access数据库读取相应数据，并根据规范的设计理论将查图过程还原为原始公式，提高了计算结果的精度。（4）渠道抗冻胀辅助设计软件界面友好，操作简单，实用性强。软件运行结果与人工计算结果完全吻合，因此软件计算结果正确可靠，精度满足要求，设计成果能够为实际工程所应用，且大大提高了渠道抗冻胀设计的工作效率。
[Abstract]:When the temperature drops below zero in winter in northern China, negative temperature has a certain destructive effect on civil engineering, especially on canal seepage control project. After frost heaving damage occurs in lining canal engineering, the efficiency of canal system project is reduced and water resources are wasted seriously. Therefore, the prevention of frost-heaving damage in these areas has become an urgent engineering problem. Accurate calculation of channel frost heaving and appropriate anti-frost heaving measures are the key directions of channel frost heaving research. In the past, the design of anti-freezing heaving of the channel was mainly manual calculation with reference to the specification, with large amount of calculation, many parameters selected in the calculation process, some parameters needed to be checked and obtained from the table, and the process of checking the chart was monotonous and tedious, and the randomness was high, and the random error was large. In order to improve the efficiency and accuracy of channel anti-frost heaving design, it is considered to develop assistant design software to replace these repetitive and complicated work. In terms of anti-freeze expansion measures, although polystyrene insulation boards are used to prevent frost expansion and damage in some areas, the specific laying thickness is generally calculated directly according to the relevant codes, and the thickness of the insulation boards is calculated directly. The calculated results are often not the most economical and reasonable, so it is necessary to optimize the laying thickness. In view of frost heaving damage of concrete lining channel, this paper discusses the research progress on channel frost heave at home and abroad, summarizes the anti-frost heaving engineering measures widely used in the channel at present. And the following research work has been done emphatically: (1) taking the Jinghui channel in Gansu as the prototype channel, the foundation soil and the lining of the canal are regarded as the whole structure. According to the isotropic permafrost medium and the finite element analysis software Abaqus, the thermal and stress coupling analysis of the lining channel with different thickness insulation plates is carried out, and the results show that the heat preservation measures are adopted under different conditions. The distribution of temperature field and displacement field. Through comparison and analysis, it is obtained that the optimal thickness of the insulation board is 8 cm for the yin-yang slope and 3 cm for the bottom of the canal. (2) the model of this paper is intended to take into account the different shading degree of the channel's Yinyang slope. The average temperature of each month during the freezing period is derived from the surface temperature of each part of the channel. It can be used for reference to the simulation model of surface temperature measurement in different parts of the channel. Through the comparison and analysis between the experimental results and the computer simulation results, the temperature field of the channel, the design of the freezing depth, and the distribution of the stress field are basically the same. The numerical simulation method presented in this paper is reasonable and feasible. (3) according to SL23-2006 "Design Code for Frost heaving of Canal system Engineering", the software of anti-frost heaving design of lining channel is developed based on C program. The software can visualize the calculation process, access the Access database to read the corresponding data, and restore the mapping process to the original formula according to the standard design theory. The accuracy of the calculation results is improved. (4) the channel anti-freeze heaving aided design software has friendly interface, simple operation and strong practicability. The result of software operation is in good agreement with the result of manual calculation. Therefore, the result of software calculation is correct and reliable, the precision meets the requirement, the design result can be applied in practical engineering, and the working efficiency of the design of channel anti-frost heaving is greatly improved.
【学位授予单位】：西北农林科技大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：TV698.26;TP391.7

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