考虑剪力滞效应的合理成桥状态的荷载检验

以某顶推施工独塔钢箱梁斜拉桥为背景,通过不同方法对比确定合理成桥状态。在此基础上,应用ANSYS软件,考虑扁平钢箱梁的剪力滞效应,对斜拉桥的成桥状态进行荷载检验,确认桥梁营运期的安全可靠。     

Benthic community and food web structure on the continental shelf of the Bay of Biscay (North Eastern Atlantic) revealed by stable isotopes analysis

The North Bay of Biscay continental shelf is a major French demersal fishery, but little was known on the trophic food web of its benthic communities. In order to determine the benthic trophic web, the objectives of this study are to describe the macro- and megafaunal benthic community structure (species richness, abundance and biomass) and to establish the trophic pathways (food sources and trophic levels) by applying carbon and nitrogen stable isotopic analysis to the main benthic and demersal species (invertebrates and fish). Two distinct benthic communities have been identified: a muddy sand community within the central part of the bay, and an outer Bay of Biscay Ditrupa sand community of higher species richness, abundance and biomass than the muddy sand community. Deposit-feeders, suspension feeders and predators, distributed in three main trophic levels, dominate both communities. Large differences in stable carbon ratio values within the primary consumers provide evidence of two different food sources: i) a pelagic food source made up of recent sedimenting particulate organic matter on which zooplankton and suprabenthos feed and ii) a benthic detrital food source supplying deposit feeders and partly benthic suspension feeders. Differences in isotopic signatures were also observed within the upper trophic levels that allowed estimation of the contribution of each food source component to the diet of the upper consumers. Finally, the use of stable isotopic composition together with the species' feeding strategy allow identification of the main differences between the trophic functioning of the two benthic communities and highlight the importance of the role of detrital pathways in the carbon cycling within the continental shelf benthic trophic web.     

光谱分析技术在船舶燃料油与气缸油配伍研究中的应用

本文叙述了用原子吸收光谱分析方法研究船用重质燃料油与不同气缸油的配伍试验时使用 Bolnes 三缸柴油机和原子吸收光谱仪,通过测定废气缸油中铁、铬含量来确定气缸磨损情况,用磨损指数和清洁分散性系统地评价配伍效果。采用该方法,可在短期运行后不需停机,拆机,即可取样测定.原子吸收光谱分析法灵敏度高,精确度强,是一种有价值的方法.     

连续箱梁混凝土结构裂缝的施工控制

结合立交箱梁施工实践,介绍箱梁结构裂缝的施工控制措施。     

滨海公路辽河特大桥索塔造型设计

通过区域背景调查分析,明确大桥设计理念和景观定位,确定索塔造型.     

浅谈海水环境的桥梁设计

通过辽宁省滨海公路的设计,积累了一些海水环境桥梁设计的经验,现总结成文,以期和同行切磋交流.     

丁坝绕流问题的紊流数学模型

本文应用水深平均k-e紊流模型,采用SIMPLEC计算方法,成功地模拟了丁坝绕流问题,并与相应的试验资料作了比较,计算结果表明该方法适用于模拟有回流存在的复杂水流。同时还探讨了模型中主要参数对回流长度的影响,并对其灵敏度作了分析计算,对参数作了修正,使计算所得的回流长度与实测值更吻合。     

沈阳市浑南大道-胜利大街互通立交总体设计

沈阳市浑南大道-胜利大街互通立交是浑南大道快速路与胜利大街快速路交汇处的枢纽型互通立交工程,是城市南部与西部联系的交通枢纽。介绍了浑南大道-胜利大街互通立交的项目背景和功能定位,采用回归分析法和双约束法对工程的交通流量进行预测,对立交总体设计、纵横断面设计及结构设计等方面进行了重点阐述和分析。     

新型的PLC的网络技术

介绍作者设计的面向工业控制与管理一体化的 SASEC- PL C网络 ,涉及网络的拓卜结构内部协议和网络工作流程 ,最后简介内部网络的物理特性     

航道整治滩性分析——非冲积性滩险滩性分析

论述了非冲积性滩险类型、基本成因、滩险碍航特点、水流特性及其分析方法。通过滩性分析可以确定滩险成滩水位、最凶水位、消滩水位(流量)的成滩出现时期及滩段凶、险的定量概念。结合滩段地貌、地形特点,确定碍航水流具体成因,并据以制定整治原则和方法。