【作者】 曾杰；

【导师】 艾长发；

【作者基本信息】 西南交通大学 ， 建筑与土木工程（专业学位）， 2018， 硕士

【摘要】 随着国家“一带一路”战略的实施,中国与各国在基建方面达成合作。目前中铁二院与俄罗斯企业中标莫斯科-喀山高铁项目,其中经过路段多为季节性冻土区,目前我国在寒区高速铁路采用的水泥混凝土封闭层结构,由于开裂、接缝渗水等问题导致基床发生冻胀、冻融等病害,影响乘车舒适性及安全性。沥青混凝土具有强度高、柔性好、减振、防水、低温抗裂等特点,很早被国外用于铁路基床结构,但在我国应用较少。对此,通过查阅文献、室内试验、数值模拟方式,对沥青混凝土用于强化基床表层结构进行动力响应及耐久性分析。论文首先结合国内外公路与铁路基层设计方法及相关文献,研究沥青混凝土强化基床表层结构使用年限的计算方法,并用此方法设计出莫喀高铁项目中强化基床表层结构合理厚度。其次,以ABAQUS有限元软件为计算工具,研究强化基床表层结构在移动荷载下的动力响应问题。最后,应用沥青混凝土损伤理论,研究此结构在循环荷载条件下沥青层损伤过程及力学性能变化过程。论文结果表明:7cm以及12cm厚度的沥青混凝土强化基床表层结构满足莫喀高铁中重货以及高速客车荷载下使用年限要求;沥青混凝土强化基床表层能有效改善基床受力情况,其中7cm厚度沥青混凝土层是一个理想厚度;在施加100万次循环荷载后7-12cm厚度的沥青层结构均没有发生破坏,当沥青层厚度越厚,其层底初始损伤越大,但损伤扩展速度更慢,最后在作用40万次荷载后处于稳定阶段,同时沥青层越厚,其沥青层的应力以及应变等力学性能更加优良、耐久性更好。论文的研究成果对于今后沥青混凝土强化基床表层结构设计具有指导意义,为今后铁路基床设计提供了有价值的参考依据。更多还原

【Abstract】 With the implementation of the national "The Belt and Road" strategy,China and other countries cooperate in infrastructure construction.The China Railway Eryuan Engineering and Russian companies won the bid for the Moscow-Kazan high-speed rail project,most of the road sections are seasonal frozen areas.At present,the concretewaterproof layer used in high-speed railways in China has problems such as cracking and other problems,which can cause frostbite,freeze-thaw and other hazards on the bed,affecting ride comfort and safety.Asphalt concrete has the characteristics of high strength,good flexibility,vibration reduction,waterproof,low temperature crack resistance,etc.Very early used abroad for railway bed structure but less applied in our country.In this regard,by consulting literature,laboratory tests,and numerical simulations,Analysis of Dynamic Response and Durability of Asphalt Concrete Used to Strengthen Surface Structure of Subgrade Bed.The paper firstly combines domestic and international road and railway basic design methods and related literatures to study the calculation method of the service life of the surface layer of the reinforced concrete bed of asphalt concrete,and uses this method to design the reasonable thickness of the surface structure of the reinforced bed in the Moka high-speed rail project.Secondly,using ABAQUS finite element software as a calculation tool,the dynamic response problems of the reinforced subgrade surface structure under moving loads are studied.Finally,the asphalt concrete damage theory was applied to study the damage process and mechanical properties of the asphalt layer under cyclic loading.The results of the thesis indicate that the surface structure of the reinforced concrete bed of asphalt reinforced concrete with 7cm and 12 cm thickness meets the requirements of the Moka High-speed Rail for heavy cargo and high-speed passenger car loads;the surface layer of the asphalt concrete reinforced bed can effectively improve the stress of the bed,and the thickness 7cm is an ideal thickness;the asphalt layer structure with a thickness of 7-12 cm has not been damaged after 1 million cyclic loads.When the asphalt layer thickness is thick,the initial damage at the bottom of the asphalt layer is larger,but the damage is slower.Finally,it is in a stable stage after 400,000 loads,and the thicker the asphalt layer,the better the asphalt layer’s mechanical properties such as stress and strain,and better durability.The research results of the thesis have guiding significance for the design of the surface structure of the reinforced asphalt concrete bed in the future,and provide a valuable reference for the future design of the railway bed.更多还原