工程科学学报，第40卷，第12期：1476-1487,2018年12月 Chinese Journal of Engineering,Vol.40,No.12:1476-1487,December 2018 DOI:10.13374/j.issn2095-9389.2018.12.005;http://journals.ustb.edu.cn 剧烈瓦斯爆炸隧道洞口致损机理 李志鹏”，吴顺川12)区 1)北京科技大学土木与资源工程学院，北京1000832)昆明理工大学国土资源工程学院，昆明650093 区通信作者，E-mail:wushunchuan@163.com 摘要为探究洛带古镇隧道瓦斯爆炸下洞口衬砌致损机理，对隧道内积聚瓦斯等效、量化研究，采用LS-DYNA建立与洞门 几何结构一致的流固耦合数值模型并验证，以RHT模型模拟混凝土并修正参数，对爆炸过程中冲击波的传播特征及强度、洞 门致损机理研究分析，并将模拟结果与实际情况对比.研究表明：爆炸冲击波在隧道内无规则的反射效应使其强度剧增、流场 复杂，局部位置有聚焦现象，隧道内高压达1.2~2.4MP:传播过程中，靠衬砌一侧冲击波运动速度较快，形态也由“球状”变 为“喇叭”状：当以平面波形态传至洞门时，拱顶冲击波强度增加56%，达2.8MP,并在削竹式洞门周边发生衍射：自隧道传出 后，强度逐渐降低，边墙及底板处的冲击波沿纵向径直射出，拱部冲击波向斜上方运动，形成“蘑菇云”.爆炸作用下，衬砌曲 边墙脚处完全破坏：爆心距7m范围内衬砌受损严重：7~15m范围内拱部几乎未受损；洞门受损严重.缺少围岩的约束作用， 洞门拱顶Y向、拱脚X向位移分别达0.26和0.14m,迎爆面、背爆面拉应力分别介于7.9~31.5MPa,4.9~15.6MPa,背爆面 出现多个应力峰值，洞门主要为受拉致损.经对比，洞门损伤特征的数值模拟结果与现场实际情况基本一致，可为后续的衬砌 灾害处治提供依据。 关键词瓦斯爆炸：隧道洞门；冲击波传播：动力响应；损伤机理 分类号TU45 Damage mechanism of tunnel portal subjected to severe gas explosion LI Zhi-peng,WU Shun-chuan) 1)School of Civil and Resources Engineering,University of Science and Technology Beijing,Beijing 100083,China 2)Faculty of Land Resources Engineering,Kunming University of Science and Technology,Kunming 650093,China Corresponding author,E-mail:wushunchuan@163.com ABSTRACT To investigate the damage mechanism of tunnel portal subjected to gas explosion in the Luodaiguzhen tunnel,equivalent and quantitative studies were carried out on the accumulation of gases in the tunnel,and a fully coupled numerical model with dimen- sions that were consistent with the actual dimensions was established by LS-DYNA and verified.The RHT model was used to simulate the concrete,and some parameters were modified.The propagation traits and strength of the blast shock wave and the damage mecha- nism of the tunnel portal were studied.The studies show that the strength of the shock wave is significantly enhanced due to its numer- ous irregular reflection.This results in a complicated wave field.The wave aggregates in local regions,and the pressure in the tunnel is 1.2-2.4 MPa.The wave near the lining travels faster during propagation,and its shape changes from the spherical to horn.The strength of the wave in the vault of the tunnel portal is increased by 56%to reach 2.8 MPa,and diffraction occurs in the vicinity of tun- nel portal.After the wave is propagated from the tunnel,its strength gradually decreases,and the wave,which originally moves along the sidewall and floor,continues to travel along the longitudinal direction.The shock wave along the arch moves upward and forms a "mushroom cloud."The corner of the sidewall is destroyed completely during the explosion,and the lining suffers serious damage with- in 7m of detonation,and the arch is almost intact in the range of 7-15 m.The tunnel portal is also severely damage.Without the con- straint of surrounding rock,the displacement of the vault in the Y and Y directions of the portal is 0.26 and 0.14 m,respectively,and 收稿日期：2018-06-25工程科学学报,第 40 卷,第 12 期:1476鄄鄄1487,2018 年 12 月 Chinese Journal of Engineering, Vol. 40, No. 12: 1476鄄鄄1487, December 2018 DOI: 10. 13374 / j. issn2095鄄鄄9389. 2018. 12. 005; http: / / journals. ustb. edu. cn 剧烈瓦斯爆炸隧道洞口致损机理 李志鹏1) , 吴顺川1,2) 苣 1) 北京科技大学土木与资源工程学院, 北京 100083 2) 昆明理工大学国土资源工程学院, 昆明 650093 苣通信作者, E鄄mail: wushunchuan@ 163. com 摘 要 为探究洛带古镇隧道瓦斯爆炸下洞口衬砌致损机理,对隧道内积聚瓦斯等效、量化研究,采用 LS鄄鄄DYNA 建立与洞门 几何结构一致的流固耦合数值模型并验证,以 RHT 模型模拟混凝土并修正参数,对爆炸过程中冲击波的传播特征及强度、洞 门致损机理研究分析,并将模拟结果与实际情况对比. 研究表明:爆炸冲击波在隧道内无规则的反射效应使其强度剧增、流场 复杂,局部位置有聚焦现象,隧道内高压达 1郾 2 ~ 2郾 4 MPa;传播过程中,靠衬砌一侧冲击波运动速度较快,形态也由“球状冶变 为“喇叭冶状;当以平面波形态传至洞门时,拱顶冲击波强度增加 56% ,达 2郾 8 MPa,并在削竹式洞门周边发生衍射;自隧道传出 后,强度逐渐降低,边墙及底板处的冲击波沿纵向径直射出,拱部冲击波向斜上方运动,形成“蘑菇云冶. 爆炸作用下,衬砌曲 边墙脚处完全破坏;爆心距 7 m 范围内衬砌受损严重;7 ~ 15 m 范围内拱部几乎未受损;洞门受损严重. 缺少围岩的约束作用, 洞门拱顶 Y 向、拱脚 X 向位移分别达 0郾 26 和 0郾 14 m,迎爆面、背爆面拉应力分别介于 7郾 9 ~ 31郾 5 MPa、4郾 9 ~ 15郾 6 MPa,背爆面 出现多个应力峰值,洞门主要为受拉致损. 经对比,洞门损伤特征的数值模拟结果与现场实际情况基本一致,可为后续的衬砌 灾害处治提供依据. 关键词 瓦斯爆炸; 隧道洞门; 冲击波传播; 动力响应; 损伤机理 分类号 TU45 收稿日期: 2018鄄鄄06鄄鄄25 Damage mechanism of tunnel portal subjected to severe gas explosion LI Zhi鄄peng 1) , WU Shun鄄chuan 1,2) 苣 1) School of Civil and Resources Engineering, University of Science and Technology Beijing, Beijing 100083, China 2) Faculty of Land Resources Engineering, Kunming University of Science and Technology, Kunming 650093, China 苣 Corresponding author, E鄄mail: wushunchuan@ 163. com ABSTRACT To investigate the damage mechanism of tunnel portal subjected to gas explosion in the Luodaiguzhen tunnel, equivalent and quantitative studies were carried out on the accumulation of gases in the tunnel, and a fully coupled numerical model with dimen鄄 sions that were consistent with the actual dimensions was established by LS鄄鄄DYNA and verified. The RHT model was used to simulate the concrete, and some parameters were modified. The propagation traits and strength of the blast shock wave and the damage mecha鄄 nism of the tunnel portal were studied. The studies show that the strength of the shock wave is significantly enhanced due to its numer鄄 ous irregular reflection. This results in a complicated wave field. The wave aggregates in local regions, and the pressure in the tunnel is 1郾 2鄄鄄2郾 4 MPa. The wave near the lining travels faster during propagation, and its shape changes from the spherical to horn. The strength of the wave in the vault of the tunnel portal is increased by 56% to reach 2郾 8 MPa, and diffraction occurs in the vicinity of tun鄄 nel portal. After the wave is propagated from the tunnel, its strength gradually decreases, and the wave, which originally moves along the sidewall and floor, continues to travel along the longitudinal direction. The shock wave along the arch moves upward and forms a “ mushroom cloud. 冶 The corner of the sidewall is destroyed completely during the explosion, and the lining suffers serious damage with鄄 in 7 m of detonation, and the arch is almost intact in the range of 7鄄鄄15 m. The tunnel portal is also severely damage. Without the con鄄 straint of surrounding rock, the displacement of the vault in the Y and X directions of the portal is 0郾 26 and 0郾 14 m, respectively, and