油管螺纹图像处理方法研究

油管螺纹图像主要用于对螺纹形貌的观察和测量。对螺纹图像采用了低通滤波、对比度变换、高通滤波等处理方法,有效地改善了图像的质量。用于尺寸测量的螺纹牙型图像根据其直方图的特征,首先采用灰度阈值分割法分离牙型轮廓,生成二值图像,然后利用跨度最小的Roberts算子提取二值图中螺纹轮廓线,得到的轮廓边缘细致、准确,可以用于尺寸测量。     

深厚软基路堤塑料套管桩处理固结及沉降规律

塑料套管桩（TC桩）作为一种应用于深厚软土地基的地基处理技术,具有施工快速、沉降小、承载力高等优点。针对增强体加固软土地基的作用特点,分析研究了TC桩处理地基的固结及沉降规律。根据未贯穿软（弱）土层的TC桩为不透水层及加固层、下卧层为单向固结的假设及孔隙水压力连续条件,将TC桩的加固层及下卧层视为双层复合地基,运用双层地基固结理论获得加固层及下卧层的平均固结度,并在此基础上提出了TC桩处理软土地基的沉降计算方法。之后,结合岳阳至常德高速公路试验段工程对本文研究成果进行验证,结果表明采用本文方法计算的固结度及沉降值与实测成果接近,说明该计算方法是合理的。最后,综合分析了桩长、桩间距对沉降的影响,其结论可为工程实践提供理论指导。     

圆钢管套箍混凝土轴压短柱受力机理分析

应用连续介质力学理论,建立圆钢管套箍混凝土同心圆柱体混凝土受压计算模型,建立圆钢管套箍混凝土组合弹性模量理论计算公式和组合应力—应变关系全曲线理论表达式。编制相应的计算程序,进行圆钢管套箍混凝土受力全过程数值分析。从圆钢管套箍混凝土加载过程的钢管环向应力—应变关系以及核心混凝土的轴向应力—应变关系、径向应力—应变关系等方面,探讨圆钢管套箍混凝土和圆钢管混凝土力学性能之间的差别,并用试验结果验证。分析结果表明:与钢管混凝土力学性能相比,钢管套箍混凝土中核心混凝土的径向压应力、纵向强度和钢管环向拉应力增加;圆钢管套箍混凝土将套箍约束作用发挥至最大,且其极限承载力和剩余承载力高,延性好,但组合弹性模量偏小。     

水柏铁路北盘江大桥钢管混凝土拱设计

水柏铁路北盘江大桥是我国第一座铁路钢管混凝土拱桥,主桥结构采用上承式X形钢管混凝土拱,跨度236m;主拱肋及横向联接系在拱肋未灌注混凝土前为完全钢结构,在灌注混凝土后及大桥运营阶段,主拱肋为钢管混凝土结构;实腹板及上下盖板按照型钢混凝土结构设计;拱上墩座为加劲的钢箱墩座,并与拱肋连接;腹杆设计采用H形构件、节点板连接的构造;涂装层按长效防腐进行设计,拱圈钢结构外表面采用热喷涂复合涂层体系,涂层类型为喷铝合金 封闭 涂装。     

Future advanced long-haul Evacuated Tube Transport (EET) system operated by TransRapid Maglev (TRM): a multidimensional examination of performance

This paper presents a multidimensional examination of the infrastructural, technical/technological, operational, economic, environmental, social, and policy performance of the future advanced Evacuated Tube Transport (ETT) system operated by TransRapid Maglev (TRM) (the ETT-TRM system). The examination implies analyzing, modeling, and estimating selected performance criteria using the case of the Trans-Atlantic passenger transport market currently served exclusively by the Air Passenger Transport (APT) system. The purpose is to assess the ETT-TRM system’s competitive capabilities compared to those of the current and future APT system and consequently its potential contribution to mitigating impacts of both systems on society and the environment – the sustainability of the transport sector - under given conditions.     

Mind the map! The impact of transit maps on path choice in public transit

This paper investigates the impact of schematic transit maps on passengers’ travel decisions. It does two things: First, it proposes an analysis framework that defines four types of information delivered from a transit map: distortion, restoration, codification, and cognition. It then considers the potential impact of this information on three types of travel decisions: location, mode, and path choices.¹ Second, it conducts an empirical analysis to explore the impact of the famous London tube map on passengers’ path choice in the London Underground (LUL). Using data collected by LUL from 1998 to 2005, the paper develops a path choice model and compares the influence between the distorted tube map (map distance) and reality (travel time) on passengers’ path choice behavior. Results show that the elasticity of the map distance is twice that of the travel time, which suggests that passengers often trust the tube map more than their own travel experience on deciding the “best” travel path. This is true even for the most experienced passengers using the system. The codification of transfer connections on the tube map, either as a simple dot or as an extended link, could affect passengers’ transfer decisions. The implications to transit operation and planning, such as trip assignments, overcrowding mitigation, and the deployment of Advanced Transit Information System (ATIS), are also discussed.     

CG-220/100M3型低温过热器失效分析及对策

分析了CG - 2 2 0 / 10 0M3型低温过热器失效的原因 ,在进行材料的成分、力学性能、材料组织、电镜分析的同时 ,结合运行寿命分析 ,认为失效的主要原因是烟气通道堵灰严重 ,形成烟气短路 ,导致部分炉管超温 ,发生高温蠕变损伤 ,在应力的作用下 ,形成蠕变孔洞 ,进而形成裂纹 ,从而导致最终的爆裂失效。根据分析的结果 ,提出了预防措施     

管波探测法在广梧高速公路灰岩区桥梁桩基工程中的应用

介绍物探新技术管波探测法的探测机理和工作原理。结合广梧高速公路河口至平台段工程实践,介绍了管波探测法在桩基溶洞勘察方面的应用与具体操作方法,并对几种物探技术进行了比较分析。     

恶劣海况下尾轴承损毁磨损案例分析

恶劣海况下船舶的运营安全性是船舶设计的关注重点,特别是在采用类似轻压载工况航行时。根据反馈,某船东订造的两艘散货船多次三次在恶劣海况下发生尾轴承损毁磨损的情况,严重影响船舶运行安全。本文根据反馈数据进行研究分析,提出可能引起尾轴承损毁磨损的原因,并在此基础上针对性的给出实施建议,供类似船舶实际运营参考。     

高速公路塑料套管桩复合地基处理机理分析

针对公路塑料套管桩（TC桩）加固软土地基作用特点,将TC桩视为不透水桩体。在前人研究成果的基础上,根据孔隙水压力连续条件,运用一维固结理论推导加固区及下卧层的平均固结度。最后,结合岳阳至常德高速公路试验段工程对本文研究成果进行验证,结果表明采用方法计算的固结度及沉降值与实测成果接近。从而,说明该计算方法的实用性、合理性,并可为类似工程实践提供理论参考。