低路堤荷载作用下钢波纹板拱桥应变的测试研究

文中依托泗许高速安徽段工程实例,对波纹板拱桥的应变特征进行了现场测试,得出了其在车辆荷载作用下切向应变变化规律.结果表明,在低路堤荷载作用下,拱桥8/8跨位置的切向应变情况较其他位置不同,应进行特殊考虑.     

多联连续梁桥墩身水平力的计算与分析

以实际在建多联先简支后连续预应力混凝土T梁桥为例,介绍了多联连续梁桥上部纵向水平力的计算方法及其在墩身上的分配.通过梁部纵向水平力在墩身的分配计算,分析了温度力、混凝土收缩、徐变影响力、支座摩阻力及汽车制动力对墩身的作用.     

面向色觉异常人群的机动车信号灯设计研究

针对色觉异常人群在不良可视环境下对交通信号辨识困难的问题,基于目前医学上普遍认同的色盲可见光谱和色盲色彩软件,结合我国交通信号灯特点及色觉异常者的视觉特征,设计一种比较经济可行的解决方案。通过在常规信号灯设备上加装辅助信号灯,并利用软件模拟色觉异常者的视觉进行对比分析,选取对比高的颜色作为辅助灯的颜色。方案效果模拟验证结果显示,本设计方案的交通信号具有较好的可辨识度,能够提高交通安全,体现了以人为本的设计理念。     

天津市构建低碳交通体系的思考与实践

低碳交通体系已是大城市客运交通的发展趋势。为了构建低碳交通体系,天津市从全生命周期角度计量了各种客运交通方式的碳排放水平,同时,比较了国内同规模城市的交通结构,认为天津市的交通结构具有低碳发展优势。为了保持和继续优化这种交通结构,天津市通过采用高度混合的用地布局缩短出行距离,通过道路建设的理性回归保护非机动交通方式,通过合理的交通政策支持公交发展、合理限制小汽车使用,从而引导并促进高排放方式向低排放方式转化。     

EPS颗粒混合轻质土在高速公路的应用

通过EPS颗粒混合轻质士在泰州长江公路大桥项目路基填筑中的实际应用,介绍该新型填筑材料的基本特性和路用性能、设计方案、施工工艺和质量控制方法等.利用土和EPS颗粒回收料作为路堤轻质填料,可以大幅度地减轻施加于地基的附加应力,增大道路的稳定性和安全系数,还可以减少对耕地占用,减少环境污染,具有广泛的发展和应用前景.     

轻型汽车排放劣化系数计算方法的研究

分别从与排放法规中劣化系数(DF)相关的几个方面,研究了乘法DF和加法DF的优缺点,得出了两种DF计算方法在法规执行中的差异.结果表明:加法DF能保持汽车的实际排放劣化水平,而乘法DF则会使汽车排放劣化水平发生改变,放大误差;随着排放限值的降低,与加法DF相比,乘法DF使汽车更难达到排放限值;而对于排放一致性检查,两种DF在不同的区域中各有优势.     

来流速度对汽车天窗风振特性的影响

针对汽车天窗风振问题,通过理论计算求得某款轿车室内空气共振频率和发生共振的来流速度范围,然后采用大涡模拟方法对其天窗风振特性进行数值仿真,结果表明:当来流速度为15m/s时,该车产生赫姆霍兹共振,共振频率为23.4Hz,最大声压级为131dB,而来流速度对第1、第2阶模态影响较大;采用最小二乘方法拟合开口处剪切层内流向速度分布,服从双曲正切分布规律;根据Rayleigh拐点定理发现天窗开口处存在不稳定模态;速度相关分析的结果表明,靠近开口前缘的两点之间的速度互相关系数小于靠近后缘的两点之间的速度互相关系数;且来流速度越大,两点间的速度互相关系数越大;而汽车天窗后缘和底板附近等部位的风振噪声最大.     

Socio-ecological Mobility: A Research Strategy for a New Coastline

Abstract

Persistent development, population pressures, and increasing natural hazards are unequivocally changing socio-ecological systems in the coastal zone. This essay provides direction and initiates scientific dialog on the potential role of mobility in adapting to natural and social changes in coastal environments. The essay identifies four key research areas on information needed to develop coastal management actions and policies that support and recognize socio-ecological coupling in coastal areas. The proposed research includes: (1) modeling localized scenarios that illustrate the tradeoffs associated with various sea level rise adaptation, (2) assessing and consolidating mobility terminology for different applications and contexts, (3) developing solutions to synchronize the co-migration of natural environments and built infrastructure, and (4) evaluating existing or creating new transparent, equitable, and sustainable policies and incentives to support socio-ecological mobility by using case studies and social science methods to understand how people make mobility decisions in different contexts.     

Land use implications of sea level rise: A case study at myrtle beach,South Carolina

Abstract

the prospect of global warming and consequent sea level rise will have important implications for coastal communities. this article examines the land use implications of alternate sea level rise scenarios on the city of myrtle beach, south carolina. current trends as well as high and low sea level rise scenarios are superimposed on the city's beach profile and near shore contours to estimate the type and value of land development likely to be impacted.

It is found that losses associated with accelerated sea level rise would be particularly high in the city's hotel district and that overall property loss could range from 21 to 60% of the city's total property value. to lessen these potential losses, coastal communities such as myrtle beach must choose among one of three policy options including: (1) barricade the beach, (2) raise the land, and (3) implement a strategic retreat. specific alternatives within each of these options are explored in turn. the article concludes that successful development plans will incorporate ground rules sensitive to and consistent with dynamic coastal processes.     

库水位循环作用下架空斜坡式码头变形研究*

为研究山区河流库水位循环作用下码头结构变形特点,依托云南省富宁港一期工程,建立架空斜坡式码头三维有限元模型.以水岩相互作用为基础,重点研究库水位循环作用下架空斜坡式码头整体变形特点、桩基水平位移、桩顶沉降、挡土墙失稳模式;得到码头结构物变形发展趋势,同时预测架空斜坡式码头在库水位循环作用下的破坏方式,为进一步研究山区河流码头结构与库岸边坡相互作用及其时变特性提供基础.