碳纤维布在金华桥加固中的应用

碳纤维布加固段结构桥梁是一项新技术,碳纤维片材轻,现场粘贴无需重型设备,设施简便,便于桥下高空作业,可在公路桥梁上推广应用.     

钢纤维混凝土在港口铁路挡墙中的应用

分别介绍了普通混凝土和钢纤维混凝土的使用情况,分析了钢纤维混凝土的性能及其对工程的影响。指出:实践证明,钢纤维混凝土较普通混凝土,具有较高的抗拉、抗压强度,较好的韧性和耐磨性。     

引起牛蛙腹根电位的传入纤维类别分析

实验用牛蛙,以坐骨神经干复合动作电位作为监测纤维类别的指标,对引起牛蛙腹根电位(VRP)的传入纤维类别进行了分析。实验中可见,当刺激强度为0.054±0.003使时,随动作电位α波的出现,在腹根可记录到前人所报道的短潜伏期的VRP,即A类纤维引起的VRP(A—VRP)。当刺激强度增加到70T左右,在A—VRP之后出现一长潜伏期的VRP。该波与A—VRP的极性一致;在300T达最大幅度。用普鲁卡因阻滞、三角波刺激、远侧与近侧刺激对比的方法,证明了这一长潜伏期的VIIP是由C类传入诱发的,命名为C—VRP。实验结果证明:牛蛙坐骨神经的C类纤维也可诱发VRP。C—VRP似可作为一个“痛”反应指标。     

任意铺设纤维增强型层合板非线性弯曲的基本方程

利用变分原理,在Reddy高阶横向剪切变形理论基础上,建立了任意铺设纤维增强型层合板非线性弯曲的基本方程,该方程具有普遍性。由所建立的方程,计算了在均布载荷作用下,对称角铺设及正交铺设均质各向异性矩形叠层板在不同边界条件下非线性弯曲的解析解,并针对给定材料进行了数值计算。     

郑西客运专线路基工后沉降监测方案的探讨

研究目的:针对郑西客运专线湿陷性黄土区路基工后沉降控制的特殊要求,分析采用既有2种路基工后沉降监测方案存在的不足。根据光纤光栅传感技术的发展和在土木工程监测中的研究与应用,探讨光纤光栅传感器沉降监测系统在客运专线湿陷性黄土区路基工后沉降监测中应用的可行性。研究结论:通过分析与探讨,采用光纤光栅传感器沉降监测系统,可实现长距离(50 km)准分布、多测点、多参量的测量,测量精度高,可精确测出小于0.1 mm(相对基准点)的垂直位移的变化,适于长期实时监测,且不受电磁干扰。能满足郑西客运专线湿陷性黄土区路基进行长期工后沉降监测的要求。     

A real-time impact detection and diagnosis system of catenary using measured strains by fibre Bragg grating sensors

This paper describes an impact detection system using strain signals based on fibre optic sensors(FBG) for the real-time monitoring of the catenary system. The proposed detection system consists of three subsystems: a measuring system, a data processing and analysis system, and a status display and data access system. Because the strain signals obey the normal distribution, to monitor the catenary system in real time, a novel method that combines mobile standard deviation with the mobile Pauta criterion is proposed to distinguish real impact from the strain signal background. The use of this adaptive judging method reduces the misjudgment rate of impacts and improves the impact recognition accuracy. These impacts can be identified by the data analysis system, which provides impact location and their causes using the features of the catenary system. This method can simplify the detection system compared with the traditional location method. An application to a commercial metro line system indicated that the impacts on the catenary system were main caused by overlaps, expansion joints or steady arms, and were verified by correspondence with the floor plan of the catenary and manual inspection results. These results verified the reliability and effectiveness of the proposed impact detection system.     

微表处应用于隧道路面的新型组合结构研究

鉴于我国对隧道路面结构和材料的研究比较薄弱而提出的隧道路面新的结构组合型式，即在贫混凝土基层水泥混凝土路面上加铺一层微表处，这对于提高路面使用性能有一定的帮助。     

Development of a new time domain-based algorithm for train detection and axle counting

This paper presents an innovative train detection algorithm, able to perform the train localisation and, at the same time, to estimate its speed, the crossing times on a fixed point of the track and the axle number. The proposed solution uses the same approach to evaluate all these quantities, starting from the knowledge of generic track inputs directly measured on the track (for example, the vertical forces on the sleepers, the rail deformation and the rail stress). More particularly, all the inputs are processed through cross-correlation operations to extract the required information in terms of speed, crossing time instants and axle counter. This approach has the advantage to be simple and less invasive than the standard ones (it requires less equipment) and represents a more reliable and robust solution against numerical noise because it exploits the whole shape of the input signal and not only the peak values. A suitable and accurate multibody model of railway vehicle and flexible track has also been developed by the authors to test the algorithm when experimental data are not available and in general, under any operating conditions (fundamental to verify the algorithm accuracy and robustness). The railway vehicle chosen as benchmark is the Manchester Wagon, modelled in the Adams VI-Rail environment. The physical model of the flexible track has been implemented in the Matlab and Comsol Multiphysics environments. A simulation campaign has been performed to verify the performance and the robustness of the proposed algorithm, and the results are quite promising. The research has been carried out in cooperation with Ansaldo STS and ECM Spa.     

玄武岩纤维筋水泥混凝土路面光纤观测分析

结合理论研究成果,通过在纵向设置分布式光纤传感器,分析由于温度变化引起的纵筋内部应力变化情况;同时通过加载试验,了解玄武岩纤维连续配筋水泥混凝土路面在荷载作用下内部应力的变化情况,与理论计算结果进行比较,并修正理论分析模型,使得理论分析与实际受力相吻合。     

聚酯纤维对沥青混合料性能影响的研究

选用进口和国产两种聚酯纤维，通过对掺与不掺聚酯纤维的相同级配沥青混合料的高温稳定性、水稳定性、低温抗裂性及抗疲劳性能的室内对比试验研究，探讨了纤维增强沥青混合料的强度形成机理，较全面认识了纤维沥青混合料的性能。试验表明，聚酯纤维对沥青混合料的多种性能均有所改善，可在工程中参考使用。