【作者】 李虎；

【导师】 宫能平；

【作者基本信息】 安徽理工大学 ， 建筑与土木工程， 2020， 硕士

【摘要】 我国经过几十年的建设与发展,逐步形成了较为完善的交通体系,地铁隧道的建设数量不断增加,人们出行方式更加多样化,但是日益复杂的国际形势与频发的交通事故,使得城市交通安全面临着许多新的挑战。隧道一般位于交通咽喉处,而且内部空间较为封闭,一旦出现爆炸事故将会产生不可估量的损失,因此研究隧道衬砌层的抗爆性能,对我国的经济发展与国防安全具有重要的现实意义与经济价值。本文通过理论分析与数值模拟的方法,分析外部爆炸作用下隧道单层衬砌结构与泡沫混凝土复合衬砌结构的动力响应与抗爆性能,具体研究内容与结果主要包括以下几点:1.利用ANSYS/LS-DYNA建立隧道单层衬砌结构数值模型,研究隧道单层衬砌结构在外部爆炸作用下的动力响应。结果表明:在外部爆炸作用下,隧道单层衬砌结构的整体变形特征为竖向挤压、横向扩张,隧道衬砌上部结构的动力响应程度最大,动力响应程度随着衬砌结构单元深度的增加而逐渐减弱。2.研究炸药上层覆土对隧道衬砌结构动力响应的影响。结果表明:炸药上层覆土能有效封闭爆炸能量,避免能量耗散过快;炸药上层覆土密度越大,封闭的爆炸能量就越多,同时地下隧道衬砌结构的动力响应程度也会相应增大。3.研究泡沫混凝土复合衬砌结构的抗爆性能。结果表明:泡沫混凝土复合衬砌结构与单层衬砌结构相比抗爆性能更好,泡沫混凝土能够有效吸收爆炸能量,减小隧道衬砌结构的内部损伤,其中内层衬砌结构的单元有效应力降低了 31.54%～43.81%。4.研究泡沫混凝土位置与组合形式对复合衬砌结构抗爆性能的影响。结果表明:复合衬砌结构的外层衬砌厚度与内层衬砌厚度比值在1:2～1:3时抗爆性能最好;“硬-软-硬-软-硬”的五层复合衬砌结构相比于三层复合衬砌结构、单层衬砌结构,其抗爆性能更好,五层复合衬砌结构的外层衬砌与内层衬砌的单元有效应力最大能分别减少19.12%、38.8%。图[52]表[8]参[53]更多还原

【Abstract】 After decades of construction and development,China has gradually formed a relatively perfect traffic system.The number of subway tunnels is constantly increasing,and people travel in more diversified ways.However,the increasingly complex international situation and frequent traffic accidents make urban traffic safety face many new challenges.The tunnel is generally located in the traffic throat,and the internal space is relatively closed.Once the explosion accident occurs,it will bring incalculable loss.Therefore,the research on the anti-explosion performance of the tunnel lining layer has important practical significance and economic value for the development of China.Through theoretical analysis and numerical simulation verification,this paper analyzes the dynamic response and anti-explosion performance of tunnel single-layer lining structure and foamed concrete composite lining structure under the action of external explosion.Specific research contents and results mainly include the following points:1.The numerical model of single-layer lining structure was established by using the dynamic analysis software ANSYS/LS-DYNA to study the dynamic response of single-layer lining structure under the action of explosion.The simulation results show that the overall deformation characteristics of the single-layer lining structure under the action of explosion are vertical extrusion and horizontal expansion.The dynamic response of the tunnel lining superstructure under the action of external detonation is the largest and the dynamic response gradually decreases with the increase of detonation distance.2.Study the influence of overburden on the dynamic response of tunnel lining structure.The simulation results show that the overburden of explosives can effectively seal off the explosion energy and avoid energy dissipation too fast.The higher the overburden density of explosives,the more explosive energy will be sealed by overburden,and the higher the dynamic response degree of the lining structure of underground tunnels will be3.Study the anti-explosion performance of foamed concrete composite lining structure.The simulation results show that foamed concrete composite lining structure has better anti-explosion performance than monolayer lining structure,foamed concrete can effectively absorb explosion energy and reduce the damage of lining internal structure under explosion action,in which the effective stress of arch in composite lining structure decreases by 31.54%～43.81%.4.Analyze the influence of the position and combination form of foamed concrete on the anti-explosion performance of composite lining structure.The results show that the ratio of the thickness of the outer arch to the thickness of the inner arch is 1:2～1:3,and the anti-explosion performance is the best.Compared with the three-layer composite lining structure and single-layer lining structure,the five-layer composite lining structure has better anti-explosion performance.The maximum effective stress of the external arch and the internal arch of the five-layer composite lining structure can be reduced by 19.12%and 38.8%respectively.Figure[52]table[8]reference[53]更多还原