多冷媒非均质人工冻结壁弹塑性应力分析

扫码查看

原文链接

万方数据
维普

中文摘要：[目的]受制冷媒介温度差异以及被冻地层与冻结管距离差异的影响,多冷媒联合双排管冻结壁的非均匀性较为显著,为了合理评价该类冻结壁的安全性,需开展考虑非均质性的多冷媒人工冻结壁弹塑性应力分析.[方法]选取距离 1/4管距处的冻结壁作为特征截面,将该截面上的温度分布曲线等效成三段一次函数形式,并将冻结壁视为随温度成线性变化的非均质材料,分别基于 4种冻土屈服准则,推导得出多冷媒联合双排管非均质冻结壁弹塑性应力解析表达式.基于该解析表达式,对多冷媒冻结壁的受力特性进行计算,并将该计算结果与均质冻结壁计算得出的结果进行对比.[结果和结论]研究发现:(1)在盐水-二氧化碳联合双排管冻结壁中,径向应力随着相对半径r的增加而上升,环向应力在不同冻结区间(Ⅰ、Ⅱ、Ⅲ)表现出不同的变化趋势.(2)基于均质冻结壁计算理论,弹性极限状态的冻结壁的环向应力最大值出现在冻结壁内侧,弹塑性状态的冻结壁的环向应力最大值出现在弹塑性分界面处,塑性极限状态的冻结壁的环向应力最大值出现在冻结壁最外侧;而基于非均质冻结壁计算理论,冻结壁环向应力最大值始终出现在冻结壁分区界线(r=2)处.(3)在考虑非均质特性后,冻结壁的弹性极限承载力降低 1.8%,而塑性极限承载力提高 8.1%.在弹塑性状态下,对应相同塑性区相对半径,非均质冻结壁具有更高的承载力,且这种现象随着塑性区相对半径的增大而愈发明显.研究成果对富水地层多冷媒联合冻结帷幕的设计具有重要的参考价值.

外文标题：Elastoplastic stress analysis of multi-refrigerant combined heterogeneous artificial frozen wall

外文摘要：[Objective]Affected by the temperature difference of the refrigerant and the distance difference between the frozen formation and the freezing pipes,the heterogeneity of the multi-refrigerant combined double-row-pipe frozen wall is more significant.In order to evaluate the safety of such frozen wall reasonably,the elastic plastic stress analysis should be carried out for the artificial frozen wall with multi-refrigerant considering the heterogeneity.[Methods]The frozen wall at 1/4 pipe distance was selected as the characteristic section.Then,the temperature distribution curve on this section was equivalently converted to three linear functions,and the frozen wall was regarded as a heterogeneous materi-al that changes linearly with temperature.On this basis,the analytical expression of plastic-elastic stress of multi-refri-gerant combined double-row-pipe heterogeneous frozen wall was derived according to four kinds of frozen soil yield cri-teria.Based on the analytical expression,the mechanical characteristics of the multi-refrigerant frozen wall were calcu-lated,and the calculated results were compared with those of the homogeneous frozen wall.[Results and Conclusions]The study indicates that:(1)The radial stress increases with the increase of the relative radius r,and the circumferential stress shows different trends in different frozen intervals(Ⅰ,Ⅱ,Ⅲ)in the brine-CO2 combined double-row-pipe frozen wall.(2)Based on the calculation theory of the homogeneous frozen wall,the maximum circumferential stress appears on the inner side of the frozen wall in the elastic limit state,at the elastic-plastic interface of the frozen wall in the elastic-plastic state,and at the outermost side of the frozen wall in the plastic limit state.However,based on the calculation the-ory of heterogeneous frozen wall,the maximum circumferential stress always occurs at the partition boundary of frozen wall(r=2).(3)With consideration to the heterogeneity,the elastic ultimate bearing capacity of the frozen wall decreases by 1.8%,while the plastic ultimate bearing capacity increases by 8.1%.In the plastic-elastic state,the heterogeneous frozen wall has higher bearing capacity compared with that in the same relative radius of plastic zone,and this phe-nomenon becomes more obvious with the increase of the relative radius of the plastic zone.The research results have im-portant reference value for the design of multi-refrigerant combined freezing curtain in water-rich strata.

外文关键词：

artificial ground freezing methoddouble-row-pipe frozen wallmulti-refrigerant combined freezing curtainheterogeneityyield criteriaelastic-plastic analysis

作者：

王彬、梁秀玲、张子浩、蔡海兵、荣传新

展开 >

作者单位：

安徽理工大学土木建筑学院,安徽淮南 232001

中煤矿山建设集团有限责任公司博士后科研工作站,安徽合肥 230091

河南理工大学河南省地下工程与灾变防控重点实验室,河南焦作 454000

关键词：

人工地层冻结法双排管冻结壁多冷媒联合冻结帷幕非均质屈服准则弹塑性分析

基金：

国家自然科学基金项目安徽省自然科学基金项目安徽省博士后科学基金项目河南省地下工程与灾害防控重点实验室开放基金项目

项目编号：

523783842308085ME1882022B635KFKT 2023-06

出版年：

2024

DOI：

10.12363/issn.1001-1986.24.05.0337

煤田地质与勘探

中煤科工集团西安研究院

煤田地质与勘探

CSTPCD北大核心

影响因子：1.079

ISSN：1001-1986

年,卷(期)：2024.52(9)

参考文献量19