Mountain Highway Design Based on New Green Design Concepts

This article analyzes the implementation of new environmentally friendly design practices in the construction of mountain highways.It covers topics such as green highway design concepts,alignment principles,and green practices specifically for mountainous highway design.This analysis aims to provide useful insights for creating green mountain highways that meet the demands of modern times.

Disaster Reduction Decision Support System Against Debris Flows and Landslides Along Highway in Mountainous Area

Highways in mountainous areas are easy to be damaged by such natural disasters as debris flows and landslides and disaster reduction decision support system (DRDSS) is one of the important means to mitigate these disasters. Guided by the theories and technologies of debris flow and landslide reduction and supported by geographical information system (GIS), remote sensing and database techniques, a DRDSS against debris flow and landslide along highways in mountainous areas has been established on the basis of such principles as pertinence, systematicness, effectiveness, easy to use, open and expandability. The system consists of database, disaster analysis models and decisions on reduction of debris flows and landslides, mainly functioning to zone disaster dangerous degree, analyze debris flow activity, simulate debris flow deposition and diffusion, analyze landslide stability, select optimal highway renovation scheme and plan disaster prevention and control engineering. This system has been applied successfully to the debris flow and landslide treatment works along Palongzangbu Section of Sichuan-Tibet Highway.

Integrated Evaluation on Highway Engineering Geological Hazard in Mountainous Area of Enshi, Hubei

Aiming at the geological features of highway engineering in mountainous area of Enshi, Hubei Province, the principles to set up an integrated evaluation system for highway engineering geological hazard are formulated. Then, the integrated evaluation system for highway engineering geological hazard in mountainous area of Enshi is established. In the evaluation system, the first-level evaluation indices are geological development degree, geological conditions, and damaging power, whereas the second-level indices including key factors affecting main kinds of geological hazard. Meanwhile, the borders of indices are determined. At last, the method of Fuzzy Comprehensive Evaluation （FCE） is adopted to quantitatively evaluate the highway engineering geological hazard in mountainous area of Enshi.

Spatial-temporal Patterns of Land-use Change in Typical Transect Area Along China National Highway 106 During 1996-2008

Based on land-use database updated with the survey of 1996, 2000, 2004 and 2008, this paper analyzed the land-use changes in the typical transect area along National Highway 106 with the aid of GIS technology and quantitative models. The results showed that arable land had been continuously decreased from 1996 to 2008, with a loss of 65.85× 10^3 hm2 and an average decrement of 5.49×10^3 hm^2 per year, and the loss in northern areas was larger; garden land and woodland were gradually centralized to the predominance area with an increment of 25.73×10^3 hm2 and 22.37×10^3 hm2, respectively; residential and industrial land increased year after year, and the transportation land showed the equalized developing spatial pattern; the increment of construction land and encroachment on arable land in the area were deeply influenced by the national macroscopic land-use policies, the rapid advance of urbanization and the development level of the regional economy. Through this case study, it is suggested that differential land- use policies should be adopted to create good environmental conditions to guarantee food security and to promote the economic development.

Utilization of recycled solid waste as ecological reclamation materials based on plant growth experiments and soil quality analysis

During the highway construction,a large number of spoil areas will be generated while a large amount of waste slag and soil could not be rationally utilized.Besides,the vegetation recovery is slow in the spoil areas due to the soil depletion.Aiming at recycling the solid waste,the sieved engineering waste slag with local red clay and corn straw biochar was supplied to solve the problem of insufficient nutrients in engineering waste slag and soil.In addition,planting experiments of alfalfa(Medicago sativa L.)and Amorpha fruticosa L.combined with physical and chemical experiments were carried out to prove the feasibility of the novel improved substrate for the reclamation of spoil areas.The results show that the substrate's improvement effect is mainly affected by the soil to slag ratio and the biochar content.The improvement effect of soil matrix in highway spoil area decreases with the increase of the waste slag content,especially when the soil-slag ratio is less than 3,and the promotion of plants is limited.On the contrary,the improvement effect is proportional to the biochar content(3%-8%).But it is noted that the Cu and Pb in the soil will exceed the clean limit corresponding to the Nemero soil pollution index level when the biochar content is 8%.Therefore,it is recommended that the soil-slag ratio should be≥3,and the biochar content should reach 3%-5%.This research provides experimental basis and technical support for utilizing solid waste resources in the reclamation of highway spoil areas.

三支柱绝缘子的设计与研究

气体绝缘金属封闭输电线路(GIL)是一种可以克服输电走廊复杂环境限制、实现城市中心大容量输电的高电压电力传输设备。GIL主要包括三支柱绝缘子、微粒捕捉器、壳体及导体等。三支柱绝缘子作为GIL的关键零部件之一,其电气性能及机械强度直接影响着GIL的运行稳定性。从GIL整体结构设计入手,详细论述了550 kV GIL三支柱绝缘子的优化设计过程,并以电磁场理论为基础对三支柱电场进行仿真解析。通过引入“电场面积”的概念,对比不同尺寸下三支柱沿面电场强度阶梯下的面积大小,得出最优结构。该设计解决了三支柱绝缘子沿面放电的问题,为GIL的开发及应用提供参考。

居住建筑节能系统外保温层PUR板的剪切粘接强度研究

为解决国内外墙外保温发展存在的问题,简述了居住建筑常用节能保温改造方式,梳理了外保温层起鼓、产生裂缝和脱落的原因,重点设计了建筑外墙外保温层PUR板(聚氨酯板)的剪切粘接强度测试试验,采用PUR板、胶粘剂和混凝土砖块制备外保温层,探究粘接界面缺陷面积和缺陷位置这2个因素对外保温层剪切粘接强度的影响。试验结果表明,粘接缺陷面积占比变大,试件剪切粘接强度会偏低,缺陷面积超过60%时,产生的影响更加严重;缺陷位置靠前,试件的剪切粘接强度偏低,缺陷位置不对称,也会直接影响外保温层的粘接强度。

绿色节能保温硬泡聚氨酯板制备及粘接强度与性能测试

为研究绿色建筑节能保温硬泡聚氨酯板制备及剪切粘接强度性能测试,通过混合一定比例的聚醚多元醇与固化剂等原料制备建筑节能保温硬泡聚氨酯板,在不同影响因素下测试剪切粘接强度性能。结果表明,硬泡聚氨酯板制备陈化时间为1440 min时,可有效保障其导热系数稳定、可靠,加工密度宜保持在57.5~60 g/m^(3),聚醚二元醇、三元醇的配比以1∶1、3∶2为宜,此时剪切粘接强度与断裂伸长率均较高,在浸水、紫外线老化、冻融循环环境下,随着粘接面积的增长,硬泡聚氨酯板的剪切粘接强度呈上升趋势,说明制备的硬泡聚氨酯板节能保温和剪切粘接强度性能较好。

北方高寒阴湿区双拱双膜保温冷棚羊肚菌人工栽培技术

甘南高寒阴湿区发展食用菌产业具有得天独厚的自然资源条件。针对甘南高寒阴湿区的环境条件和羊肚菌生产实际,因地制宜地设计出高寒阴湿区双拱双膜保温冷棚,并从菌种选择及制备、营养袋制备、整地、栽培方式、播种、菌丝生长及出菇管理、病虫害防治、采收、加工贮藏等方面总结出了双拱双膜保温冷棚羊肚菌人工栽培技术,旨在为北方高寒阴湿区羊肚菌标准化生产和规模化种植提供技术支撑。

严寒地区地下水封洞库冬季施工保温措施的优化与应用

严寒地区水封洞库内的冬季施工存在诸多质量和安全风险,为保证施工质量和生产效率,结合现场实际,采取了一系列保温措施。重点对加热供暖能源选取的技术可行性、安全环保性、经济适用性,加热供暖设备选择的热功耗计算、材料及设备选择、供暖系统的应用,冬季施工标准与管理的质量标准、保证措施及检验方法等进行了深入的阐述。实践表明,该措施有效保障了正常施工。

12 kV/4000 A环保气体绝缘开关设备散热结构设计

由于环保气体绝缘开关设备是完全密封的,其散热工况极差,针对12 kV/4 000 A环保气体绝缘开关设备研发中的热传递与散热问题,开发了一种组装式断路器。对断路器的内部结构设计进行了优化,增大有效的散热面积,同时优化风道与风机布局来进一步扩大散热面积,强化外部热对流交换。试验结果表明,温升值完全控制在标准要求的范围内,开发的12 kV/4 000 A环保气体绝缘开关设备满足温升标准,确保了开关柜运行的可靠性。

Risk assessment of glacial debris flow on alpine highway under climate change: A case study of Aierkuran Gully along Karakoram Highway

Glacial debris flows(GDFs) often occur in alpine regions that are subject to rapid climate change, and pose a serious threat to road systems. However, the ways that climate change impacts GDF risks along road systems remain poorly understood. Aierkuran Gully, located in eastern Pamir along Karakoram Highway(KKH), is a hotspot for GDF activity and climate change, and was thus selected to investigate the GDF risk to road systems under climate change conditions. Reg CM4.6 climate data for northwestern China were selected as climate projections during baseline(2011–2020) and future periods(2031–2040) under the Representative Concentration Pathway(RCP) 8.5. To reflect the coupling effect of rainfall and melt water that triggers GDF, a glacial hydrological model DETIM that considers both factors was applied to calculate the peak debris flow discharge. A FLO-2D model was calibrated based on high-quality data collected from a detailed field investigation and historical debris flow event. The FLO-2D model was used to simulate the debris flow depth and velocity during baseline and future periods under RCP8.5. The debris flow hazard was analyzed by integrating the maximum flow depth and momentum. Road structure vulnerability was further determined based on the economic value and susceptibility of hazard-affected objects. The GDF risk along KKH was assessed based on the GDF hazard and vulnerability analysis. Our results show that climate change would lead to amplified peak debris flow discharge, trigger highermagnitude GDF, and induce more severe damage and threats to the road system. Compared with the baseline period, the debris flow damage risk for culverts and bridges would increase and the areas that inundate the road and pavement would expand. Our findings provide valuable insights for the development of mitigation strategies to adapt road systems to climate change, especially in alpine regions with highly active GDFs.

Landslide mapping and analysis along the China-Pakistan Karakoram Highway based on SBAS-InSAR detection in 2017

The Karakoram Highway(KKH),a part of the China–Pakistan Economic Corridor(CPEC),is a major highway connecting northern Pakistan to China.The inventorying and analysis of landslides along KKH are challenging because of poor accessibility,vast study area,limited availability of ground-based datasets,and the complexity of landslide processes in the region.In order to preserve life,property,and infrastructure,and to enable the uninterrupted and efficient operation of the KKH,it is essential to strengthen measures for the prevention and control of geological disasters.In the present study,SBASInSAR(Small Baseline Subsets-Interferometric Synthetic Aperture Radar)was used to process 150 scenes of Sentinel 1-A images in the year 2017 along the Karakoram Highway.A total of 762 landslides,including 57 complex landslides,126 rock falls,167 debris slides,and 412 unstable slopes,ranging in size between 0.0017 and 10.63 km2 were identified.Moreover,this study also gains an inventory of 40 active glacier movements in this region.Landslide categorization,displacements characteristics,spatial distribution,and their relationship with various contributing factors have been successfully investigated along the entire KKH using image interpretation and frequency-area statistics.The criteria adopted for landslides categorization is presented in the study.The results showed that the 2-D ground deformation derived in Hunza valley echoes well with the general regional landslides characteristics.The spatial distribution analysis revealed that there are clumped distributions of landslides in the Gaizi,Tashkurgan,and Khunjerab in China,as well as in Hunza valley,and north of Chilas city in Pakistan.Statistical results indicated that these landslides mainly occur on south-facing slopes with a slope angle of 20°–45°and elevation relief of 550–2,100 m.Landslide development is also related to low vegetation cover and weathering effects in mountain gullies.Overall,our study provides scientific data support and theoretical references for prevention,control,and mitigation of geological disasters in the Karakoram region.

Temperature monitoring of the XPS board insulated subgrade along the newly constructed Gonghe-Yushu Highway in permafrost regions

On the basis of on-site measured data of the newly constructed Gonghe-Yushu Highway in a permafrost region, this paper analyzed thermal conditions of the subgrade with XPS insulated board according to different selected monitoring sections in various locations. We also summarized the geothermal distribution and change rules of subgrade with XPS insulation board under the asphalt pavement in summarized a high temperature frozen soil region. It is suggested that the shoulder of subgrade with XPS insulation board be widen to a reasonable width so as to keep the subgrade stable.

Research on EPS application to very wide highway embankments in permafrost regions

In order to maintain the thermal stability of very wide highway embankments in permafrost regions, the thermal isolation material EPS is often utilized. To examine the effects of this insulation on the China National Highway （G214）, two-dimensional finite element analysis of temperature fields was conducted for varying widths of highway embankments with and without EPS insulation. The numerical results show that in permafrost regions the effect of thermal aggregation on asphalt pavement is more obvious when highway embankments are wider, and, specifically for the G214 highway, the insu- lation should be more than 25 cm thick for 24-m-wide embankments. However, considering other factors such as the struc tural rationality of the embankments and high engineering costs, it might not be feasible to install EPS insulation in 24-m-wide embankments of the G214 highway when the height of the embankments is less than 3.65 m.

Brief Analysis on Highway Construction and Urban Development

On the basis of studying influence of means of transportation on urban distribution and form,this paper focuses on influence of highway on modern urban areas. Results show that construction of highway accelerates urbanization,forms organic traffic network connecting large, medium and small cities and towns,and promotes development of modern urban agglomeration. Finally,it presents rational ideas of strengthening planning,integrating urban and rural development,preventing blind expansion of urban areas,and building ecological and garden cities.

夏热冬冷地区相变屋面隔热技术研究进展

相变材料与建筑围护结构相结合能够很好地降低建筑的能耗,尤其是在空调耗能比较大的夏热冬冷地区。由于太阳辐射的直接影响,屋面又没有遮挡,导致屋面内表面的温度急剧升高,耗热量也最大。就夏热冬冷地区相变屋面的隔热研究进行了综述,阐述了相变材料的制备及其封装技术,对相变屋面的隔热机理进行了详细的介绍,分析了相变材料性能对屋面的隔热效果的影响,提出了目前相变屋面在隔热方面存在的一些问题,对夏热冬冷地区相变屋面隔热发展趋势的展望。

引信的隔热与缓释结构设计及验证

为探索可满足引信在高温高热环境下热缓释要求的泄压和隔热设计方法,以RDX基炸药为装药的某引信为对象,获得了传爆药盒的最小泄压面积与不同厚度隔热材料在不同高温下的背温分布情况.对模拟件进行了快速烤燃和慢速烤燃试验验证,结果表明:泄压孔的设计能显著减弱传爆药盒的反应等级,且泄压面积的增大加强了热缓释效果;对含泄压孔设计的传爆药盒装药包覆装配胶后,一定程度上提升了装药的密封性,使得包覆后反应比无包覆的反应更加剧烈;涂覆隔热层材料可以明显延缓引信点火反应时间,但对反应剧烈程度的影响微弱.

基于FFT-OMP-DAMAS波束形成方法的汽车前围板隔声薄弱部位识别

为实现汽车前围板隔声薄弱部位的准确识别,文章提出了基于快速傅里叶变换(Fast Fourier Transform,FFT)和正交匹配追踪(Orthogonal Matching Pursuit,OMP)的反卷积(Deconvolution Approach for the Mapping of Acoustic Sources,DAMAS)波束形成方法(FFT-OMP-DAMAS)。该方法基于声源稀疏分布假设,利用正交匹配追踪思想求解反卷积问题,并进一步结合傅里叶变换和点扩散函数空间转移不变假设降低计算维度。在混响室-消声室内,分别利用延迟求和方法,DAMAS方法和FFT-OMP-DAMAS方法进行了某汽车前围板隔声薄弱部位识别试验,结果表明:FFTOMP-DAMAS方法能够有效抑制旁瓣和伪源,有效缩减主瓣宽度,从而准确识别汽车前围板隔声薄弱部位,且相较于传统的DAMAS方法,文中提出的FFT-OMP-DAMAS方法能获得更清晰的成像结果,计算效率有了明显提高。