青藏高寒高海拔地区宽幅公路沥青路面力学响应
|
摘要
为深入研究青藏高寒高海拔地区宽幅公路沥青路面力学响应,以指导该区域宽幅公路沥青路面结构设计、路基填挖形式及高度选择。将基于欧拉描述的大变形固结理论应用于冻土融化固结分析,研究融沉作用下路基高度、路面结构形式、宽度、厚度及模量对宽幅公路沥青路面力学响应的影响规律,并基于多目标规划理念,提出以沥青层底拉应变及路表差异沉降量综合最小为目标的力学响应综合评价指标P,用以评价路面综合力学响应。结果表明:柔性基层沥青路面沥青层底拉应变随路表差异沉降量呈先增大后减小的变化规律,倒装式、半刚性及复合式基层沥青路面、半刚性底基层层底拉应力则随其呈线性增大趋势;融沉作用下,ATB-25层底横向拉应变小于不考虑冻土融沉作用时;年均气温为-3.5℃、-4.5℃时,半刚性底基层横向拉应力显著大于不考虑冻土融沉作用时;P均值随路面宽度增大而增大,且22.5m时增大最显著;填方路基P均值随填方高度增大先减小后增大,高度为1m时最大,2m时最小,此后逐渐增大;挖方路基P均值随挖方高度增大而增大,高度为1m时最小,2m时显著增大。从路面力学响应角度,建议多年冻土区宽幅公路应尽量减小路面宽度,不宜大于17.5m;路基填方高度不宜小于2m,挖方高度宜为1m以下;对于年均气温-3.5℃、-4.5℃地区,路面结构形式宜选取柔性基层沥青路面。
The mechanical response of high-grade highway asphalt pavement in a cold and highaltitude area in Qinghai-Tibet Plateau was investigated to guide the pavement structural design,subgrade form,and height selection of a high-grade highway.A large-deformation consolidation theory based on Euler's description was applied to analyze the melting and consolidation of frozen soil,and the effects of the subgrade height,pavement structure,width,thickness,and modulus on the mechanical response of high-grade asphalt pavement were analyzed.Based on themultiobjective planning concept,the comprehensive evaluation index P for the mechanical response was proposed to evaluate the comprehensive mechanical response of the pavement,with the objective of minimizing the tensile strain of the asphalt bottom layer and the differential settlement of the pavement.The results show that the tensile strain at the bottom asphalt layer of the flexible pavement increases first and then decreases with increasing of the pavement differential settlement.The tensile stresses at the semirigid base layer of the semirigid,composite,and inverted asphalt pavement shows a linearly increas.Under the action of thaw settlement,the transverse tensile strain at the bottom of the ATB-25 layer is lower than the corresponding value without considering the thaw settlement of the frozen soil.When the annual average temperature is-3.5℃and-4.5℃,the transverse tensile stress of the semirigid base layer is significantly higher than the P value without considering the thaw settlement of the frozen soil.The P of the pavement mechanical response increases with pavement width increasing,when the pavement width is 22.5 m,is largest.The average Pvalue decreases first and then increases with increasing embankment height,when the embankment height is 1 mis largest and when the embankment height is 2 m is smallest.It increases with increasing excavation height,when the excavation height is 1 mis smallest and when the subgrade height is2 mincreases significantly.From the perspective of the pavement mechanical response,it is suggested that the pavement width should be maximally reduced in permafrost areas.The pavement width of a high-grade highway should not exceed 17.5 m.The height of the embankment should be no less than 2 m.The height of the excavation should be less than 1 m.For areas with average temperatures of-3.5℃and-4.5℃,flexible pavement should be selected as the pavement structure.12 tabs,9 figs,22 refs.
The mechanical response of high-grade highway asphalt pavement in a cold and highaltitude area in Qinghai-Tibet Plateau was investigated to guide the pavement structural design,subgrade form,and height selection of a high-grade highway.A large-deformation consolidation theory based on Euler's description was applied to analyze the melting and consolidation of frozen soil,and the effects of the subgrade height,pavement structure,width,thickness,and modulus on the mechanical response of high-grade asphalt pavement were analyzed.Based on themultiobjective planning concept,the comprehensive evaluation index P for the mechanical response was proposed to evaluate the comprehensive mechanical response of the pavement,with the objective of minimizing the tensile strain of the asphalt bottom layer and the differential settlement of the pavement.The results show that the tensile strain at the bottom asphalt layer of the flexible pavement increases first and then decreases with increasing of the pavement differential settlement.The tensile stresses at the semirigid base layer of the semirigid,composite,and inverted asphalt pavement shows a linearly increas.Under the action of thaw settlement,the transverse tensile strain at the bottom of the ATB-25 layer is lower than the corresponding value without considering the thaw settlement of the frozen soil.When the annual average temperature is-3.5℃and-4.5℃,the transverse tensile stress of the semirigid base layer is significantly higher than the P value without considering the thaw settlement of the frozen soil.The P of the pavement mechanical response increases with pavement width increasing,when the pavement width is 22.5 m,is largest.The average Pvalue decreases first and then increases with increasing embankment height,when the embankment height is 1 mis largest and when the embankment height is 2 m is smallest.It increases with increasing excavation height,when the excavation height is 1 mis smallest and when the subgrade height is2 mincreases significantly.From the perspective of the pavement mechanical response,it is suggested that the pavement width should be maximally reduced in permafrost areas.The pavement width of a high-grade highway should not exceed 17.5 m.The height of the embankment should be no less than 2 m.The height of the excavation should be less than 1 m.For areas with average temperatures of-3.5℃and-4.5℃,flexible pavement should be selected as the pavement structure.12 tabs,9 figs,22 refs.
引文
[1]徐学祖,王家澄,张立新.冻土物理学[M].2版.北京:科学出版社,2001.XU Xue-zu,WANG Jia-cheng,ZHANG Li-xin.Frozen soil physics[M].2nd ed.Beijing:Science Press,2001.
[2]柯洁铭,杨平.冻土冻胀融沉的研究进展[J].南京林业大学学报:自然科学版,2004,28(4):105-108.KE Jie-ming,YANG Ping.The advance of research on the frost heave and thawing settlement of frozen soil[J].Journal of Nanjing Forestry University:Natural Sciences Edition,2004,28(4):105-108.
[3]SORAB P,YAVUZ C.Solution and evaluation of permafrost thaw-subsidence model[J].Journal of Engineering Mechanics,1995,121(3):460-469.
[4]陈肖柏,刘建坤,刘鸿绪,等.土的冻结作用与地基[M].北京:科学出版社,2006.CHEN Xiao-bai,LIU Jian-kun,LIU Hong-xu,et al.Frost action of soil and foundation engineering[M].Beijing:Science Press,2006.
[5]侯曙光,沙爱民.土体冻融过程温度场与位移场耦合分析[J].长安大学学报:自然科学版,2009,29(5):25-29.HOU Shu-guang,SHA Ai-min.Temperature-displacement field coupling analysis in freeze-thaw process of soil[J].Journal of Chang'an University:Natural Science Edition,2009,29(5):25-29.
[6]石峰,刘建坤.109国道冻土路基动力融化固结研究[J].北京交通大学学报,2013,37(4):59-63.SHI Feng,LIU Jian-kun.Study on experiment and numerical simulation of melting consolidation of 109National Highway[J].Journal of Beijing Jiaotong University,2013,37(4):59-63.
[7]ZHANG M,PEI W,LI S,et al.Experimental and numerical analysis of thermal-mechanical stability of an embankment with shady and sunny slopes in permafrost regions[J].Applied Thermal Engineering,2017,127:1478-1487.
[8]YUAN C,YU Q,YOU Y,et al.Deformation mechanism of an expressway embankment in warm and high ice content permafrost regions[J].Applied Thermal Engineering,2017,121:1032-1039.
[9]陶祥令,马金荣,黄凌.人工冻土融沉试验及融沉系数预测研究[J].采矿与安全工程学报,2015,32(6):996-1003.TAO Xiang-ling,MA Jin-rong,HUANG Ling.Astudy of the prediction of artificial frozen soil thaw settlement test and thaw settlement coefficient[J].Journal of Mining and Safety Engineering,2015,32(6):996-1003.
[10]严学斌,许兆义,魏静.青藏铁路低温冻土区片石路基的温度特征[J].北京交通大学学报,2010,34(1):73-77.YAN Xue-bin,XU Zhao-yi,WEI Jing.Temperature characteristics of subgrade with rock berm in low temperature frozen ground of Qinghai-Tibet Railway[J].Journal of Beijing Jiaotong University,2010,34(1):73-77.
[11]SUN Q,CHANG J.Thaw settlement prediction of permafrost subgrade based on support vector machine[J].Medical Physics,2014,41(10):250-253.
[12]孙全胜,常继峰.基于支持向量机的多年冻土路基融沉变形预测[J].公路工程,2014,39(5):136-140.SUN Quan-sheng,CHANG Ji-feng.Thaw settlement prediction of permafrost subgrade based on support vector machine[J].Highway Engineering,2014,39(5):136-140.
[13]LUO L,MA W,ZHANG Z,et al.Freeze/thaw-induced deformation monitoring and assessment of the slope in permafrost based on terrestrial laser scanner and GNSS[J].Remote Sensing,2017,9(3):198-204.
[14]钟勇强,黄晓明,廖公云,等.融沉变形对柔性路面应力应变影响试验研究[J].东南大学学报:自然科学版,2011,41(1):181-185.ZHONG Yong-qiang,HUANG Xiao-ming,LIAOGong-yun,et al.Influence of thawing settlement deformation on stress and strain in flexible pavement[J].Journal of Southeast Uneversity:Natural Science Edition,2011,41(1):181-185.
[15]来胜祥.多年冻土地区路基热稳定性分析和路面结构响应研究[D].北京:北京交通大学,2012.LAI Sheng-xiang.Analysis of roadbed thermal stability and study on the pavement structure response in the permafrost subgrade[D].Beijing:Beijing Jiaotong University,2012.
[16]穆柯,金龙,朱东鹏,等.多年冻土区路基尺度效应对路面结构力学响应的影响[J].冰川冻土,2014,36(4):862-869.MU Ke,JIN Long,ZHU Dong-peng,et al.Study of the pavement structure mechanical response of scale effects of subgrade in permafrost regions[J].Journal of Glaciology and Geocryology,2014,36(4):862-869.
[17]张久鹏,袁卓亚,汪双杰,等.冻土融沉对路面结构力学响应的影响[J].长安大学学报:自然科学版,2014,34(4):7-12.ZHANG Jiu-peng,YUAN Zhuo-ya,WANG Shuangjie,et al.Effect analysis of thaw settlement of permafrost on mechanical responses of pavement structure[J].Journal of Chang'an University:Natural Science Edition,2014,34(4):7-12.
[18]黄喆.青藏高寒高海拔地区合理路面结构研究[D].西安:长安大学,2017.HUANG Zhe.Study on reasonable pavement structure in high altitude and cold area[D].Xi'an:Chang'an University,2017.
[19]BAO H.Development of an enthalpy-based frozen soil model and its validation in a cold region in China[J].Journal of Geophysical Research:Atmospheres,2016,121(10):5259-5280.
[20]QIANG F,HOU R,LI T,et al.Soil moisture-heat transfer and its action mechanism of freezing and thawing soil[J].Transactions of the Chinese Society for Agricultural Machinery,2016,21(6):139-148.
[21]丁洲详.欧拉描述的大变形固结理论及其有限元法[D].西安:长安大学,2002.DING Zhou-xiang.Euler's description of large deformation consolidation theory and finite element method[D].Xi'an:Chang'an University,2002.
[22]汪双杰,黄晓明.冻土地区道路设计理论与实践[M].北京:科学出版社,2012.WANG Shuang-jie,HUANG Xiao-ming.Design theory and practice of the road in frozen soil regions[M].Beijing:Science Press,2012.
[2]柯洁铭,杨平.冻土冻胀融沉的研究进展[J].南京林业大学学报:自然科学版,2004,28(4):105-108.KE Jie-ming,YANG Ping.The advance of research on the frost heave and thawing settlement of frozen soil[J].Journal of Nanjing Forestry University:Natural Sciences Edition,2004,28(4):105-108.
[3]SORAB P,YAVUZ C.Solution and evaluation of permafrost thaw-subsidence model[J].Journal of Engineering Mechanics,1995,121(3):460-469.
[4]陈肖柏,刘建坤,刘鸿绪,等.土的冻结作用与地基[M].北京:科学出版社,2006.CHEN Xiao-bai,LIU Jian-kun,LIU Hong-xu,et al.Frost action of soil and foundation engineering[M].Beijing:Science Press,2006.
[5]侯曙光,沙爱民.土体冻融过程温度场与位移场耦合分析[J].长安大学学报:自然科学版,2009,29(5):25-29.HOU Shu-guang,SHA Ai-min.Temperature-displacement field coupling analysis in freeze-thaw process of soil[J].Journal of Chang'an University:Natural Science Edition,2009,29(5):25-29.
[6]石峰,刘建坤.109国道冻土路基动力融化固结研究[J].北京交通大学学报,2013,37(4):59-63.SHI Feng,LIU Jian-kun.Study on experiment and numerical simulation of melting consolidation of 109National Highway[J].Journal of Beijing Jiaotong University,2013,37(4):59-63.
[7]ZHANG M,PEI W,LI S,et al.Experimental and numerical analysis of thermal-mechanical stability of an embankment with shady and sunny slopes in permafrost regions[J].Applied Thermal Engineering,2017,127:1478-1487.
[8]YUAN C,YU Q,YOU Y,et al.Deformation mechanism of an expressway embankment in warm and high ice content permafrost regions[J].Applied Thermal Engineering,2017,121:1032-1039.
[9]陶祥令,马金荣,黄凌.人工冻土融沉试验及融沉系数预测研究[J].采矿与安全工程学报,2015,32(6):996-1003.TAO Xiang-ling,MA Jin-rong,HUANG Ling.Astudy of the prediction of artificial frozen soil thaw settlement test and thaw settlement coefficient[J].Journal of Mining and Safety Engineering,2015,32(6):996-1003.
[10]严学斌,许兆义,魏静.青藏铁路低温冻土区片石路基的温度特征[J].北京交通大学学报,2010,34(1):73-77.YAN Xue-bin,XU Zhao-yi,WEI Jing.Temperature characteristics of subgrade with rock berm in low temperature frozen ground of Qinghai-Tibet Railway[J].Journal of Beijing Jiaotong University,2010,34(1):73-77.
[11]SUN Q,CHANG J.Thaw settlement prediction of permafrost subgrade based on support vector machine[J].Medical Physics,2014,41(10):250-253.
[12]孙全胜,常继峰.基于支持向量机的多年冻土路基融沉变形预测[J].公路工程,2014,39(5):136-140.SUN Quan-sheng,CHANG Ji-feng.Thaw settlement prediction of permafrost subgrade based on support vector machine[J].Highway Engineering,2014,39(5):136-140.
[13]LUO L,MA W,ZHANG Z,et al.Freeze/thaw-induced deformation monitoring and assessment of the slope in permafrost based on terrestrial laser scanner and GNSS[J].Remote Sensing,2017,9(3):198-204.
[14]钟勇强,黄晓明,廖公云,等.融沉变形对柔性路面应力应变影响试验研究[J].东南大学学报:自然科学版,2011,41(1):181-185.ZHONG Yong-qiang,HUANG Xiao-ming,LIAOGong-yun,et al.Influence of thawing settlement deformation on stress and strain in flexible pavement[J].Journal of Southeast Uneversity:Natural Science Edition,2011,41(1):181-185.
[15]来胜祥.多年冻土地区路基热稳定性分析和路面结构响应研究[D].北京:北京交通大学,2012.LAI Sheng-xiang.Analysis of roadbed thermal stability and study on the pavement structure response in the permafrost subgrade[D].Beijing:Beijing Jiaotong University,2012.
[16]穆柯,金龙,朱东鹏,等.多年冻土区路基尺度效应对路面结构力学响应的影响[J].冰川冻土,2014,36(4):862-869.MU Ke,JIN Long,ZHU Dong-peng,et al.Study of the pavement structure mechanical response of scale effects of subgrade in permafrost regions[J].Journal of Glaciology and Geocryology,2014,36(4):862-869.
[17]张久鹏,袁卓亚,汪双杰,等.冻土融沉对路面结构力学响应的影响[J].长安大学学报:自然科学版,2014,34(4):7-12.ZHANG Jiu-peng,YUAN Zhuo-ya,WANG Shuangjie,et al.Effect analysis of thaw settlement of permafrost on mechanical responses of pavement structure[J].Journal of Chang'an University:Natural Science Edition,2014,34(4):7-12.
[18]黄喆.青藏高寒高海拔地区合理路面结构研究[D].西安:长安大学,2017.HUANG Zhe.Study on reasonable pavement structure in high altitude and cold area[D].Xi'an:Chang'an University,2017.
[19]BAO H.Development of an enthalpy-based frozen soil model and its validation in a cold region in China[J].Journal of Geophysical Research:Atmospheres,2016,121(10):5259-5280.
[20]QIANG F,HOU R,LI T,et al.Soil moisture-heat transfer and its action mechanism of freezing and thawing soil[J].Transactions of the Chinese Society for Agricultural Machinery,2016,21(6):139-148.
[21]丁洲详.欧拉描述的大变形固结理论及其有限元法[D].西安:长安大学,2002.DING Zhou-xiang.Euler's description of large deformation consolidation theory and finite element method[D].Xi'an:Chang'an University,2002.
[22]汪双杰,黄晓明.冻土地区道路设计理论与实践[M].北京:科学出版社,2012.WANG Shuang-jie,HUANG Xiao-ming.Design theory and practice of the road in frozen soil regions[M].Beijing:Science Press,2012.