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181.
论述了工业废渣即粉煤灰、液态渣和七0砂材料在路面基层中的应用,同时通过试验和弯沉值的测定,给出了二灰混合料的回弹模量值和补强设计参数。  相似文献   
182.
路基、路面回弹模量是设计和施工的重要指标,但回弹模量是变化的线性函数,较难直接测量,在施工中采用了路基弯沉测量来间接控制回弹模量。用多层弹性体系理论方法全方位阐述路基路面各层回弹模量与总弯沉值的关系,给出施工过程中控制弯沉值的理论标准。用此方法计算理论弯沉值可以在实际施工中及时了解路基质量情况。  相似文献   
183.
论和谐社区建设   总被引:1,自引:0,他引:1  
社区是社会的基本细胞,建设和谐社区是构建和谐社会的基础。和谐社会的建设必须把握社区的本质与基本特征,明确和谐社区的内涵与标准,发挥社区的基本功能和作用。  相似文献   
184.
针对地铁车站超深基坑开挖坑内隆起的预估分析,在静止侧压力系数室内试验仪上对上海的土层土样进行加荷-卸荷试验模拟基坑的开挖。通过对试验数据的进一步分析整理,采用侧向应力松弛法以及卸荷比与回弹模量的关系规律来研究基坑开挖回弹的规律,以便在地铁车站超深基坑开挖中采用合适的工程措施,从而保证工程的安全,并为其他工程应用提供借鉴和参考。  相似文献   
185.
One of the major barriers to addressing complex social–ecological issues through integrated coastal management (ICM) is a lack of intergovernmental coordination and cooperation (horizontal and vertical fragmentation). This article describes an effort to overcome the barriers to ICM in Sri Lanka by fostering intergovernmental collaboration and initiating adaptive governance to restore one town, Hikkaduwa, and its associated marine protected area (MPA) and coastal zone habitats. Administrators from 12 national and local governmental agencies that are responsible for aspects of coastal management in the town of Hikkaduwa participated in a series of formal and informal workshops and a week-long tour of ICM projects in the Philippines. Outcomes demonstrate that these informal and formal meetings, workshops, and travel experiences fostered trust, social capital, and attitudinal organizational commitment (AOC). The experiences motivated members to overcome vertical and horizontal governance fragmentation through the formation of an independent intergovernmental committee for the restoration of Hikkaduwa into a sustainable and resilient community. ICM activities undertaken by the newly formed organization suggest that internal leadership capacity, effective local–national partnerships, explicitly linked ecological–economic projects, and long-term commitment are necessary conditions for success. Overall, attainment of sustainability and resilience through successful ICM should be thought of as a journey and not a destination.  相似文献   
186.
文章基于特征点弯沉等效原理,采用弹性层状体系和有限元方法,模拟刚性承载板的加载模式,以处治土路基顶面回弹模量满足规范要求为原则,引入公路重要性和施工变异性系数,给出了路基无机结合料处治深度的确定方法,并针对不同公路等级给出了路基处治深度的建议值。  相似文献   
187.
The East Sea (Sea of Japan) is a unique marginal sea because it exhibits features of oceanic dynamics of much larger ocean basins. This semi-enclosed basin may be considered as a model or microcosm for understanding of how biological processes and distributions in pelagic ecosystem are interacting with physical processes in highly dynamic ocean regions. This overview summarizes the recent progresses concerning spatial and temporal variability of pelagic ecosystem components form an interdisciplinary point of view. Spatial characteristics of physical environments and biogeography in the region are distinguished mainly by the subpolar front. It was also found that long-term changes in biomass and community structure as well as those in the physical and biological environments are associated with climate variability in the region. We conclude by identifying main needs for the information and researches, particularly regular and long-term sampling, and permanent monitoring if possible.  相似文献   
188.
针对交通运输行业在新型冠状病毒肺炎疫情防控和应急保障中面临的形势与问题,从系统韧性角度出发,结合此次疫情的突发性和新特点,分析了交通运输行业作为复杂动态系统在疫情防控中的作用和挑战。充分借鉴联合国、美国、欧盟、英国和日本等关于韧性交通运输系统构建和交通应急保障的经验,梳理出交通运输行业系统韧性分析要点。从疫情防控与应急保障两方面,提出了建设韧性交通运输体系、做好客货运输保障和丰富应急管理手段等措施建议,以期有利于当前疫情防控工作,并为下一阶段综合交通网建设及交通运输应急保障能力提升提供参考。  相似文献   
189.
结合新疆特殊的自然环境条件,深入研究新疆地貌、水文、气温、土壤、植被、常见自然病害等自然环境条件的区域差异及其对公路建设的影响,阐述相关的工程经验及治理措施,为新疆地区的公路建设提供引导和依据。  相似文献   
190.
Rapid urban expansion in China has created both opportunities and challenges for promoting active transport in urban residential communities. Previous studies have shown that the urban form at the city scale has affected active transport in Chinese cities. However, there is less agreement about how the physical and social variations of neighborhood types should be addressed. This research investigates the four most representative neighborhood types found in Chinese cities: traditional mixed-use, slab block work-unit, gated community, and resettlement housing. Household travel diaries conducted in Chengdu in 2016 were analyzed using binary logistic regressions, supplemented by informal onsite interviews. The findings indicate significant variations in the use and accessibility of active transport in each neighborhood type for non-work trips. This suggests that each neighborhood type may need different strategies for promoting active transport: (1) the traditional mixed-use neighborhoods are in need of intensified urban retrofitting projects to reclaim public open space; (2) the work-unit could benefit from comprehensive plans rather than a patchwork of projects; (3) while opening up gated communities can improve porosity across neighborhoods and promote active transport, the more pressing issue may be their inability to keep up with the transportation needs of the residents; and (4) residents of resettlement housing should have better access to employment using transit and non-motorized modes.  相似文献   
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