Rapid geomorphological reconnaissance survey for road alignment in West Nepal

A rapid geomorphological reconnaissance survey of the 112 km Baitadi-Darchula road currently under construction in the Middle Himalaya of West Nepal is described. The first 39 km of the proposed road was under construction when this 5 day survey commenced, to cover both the initial segment as well as an examination of the stability and practicability of the remainder of the alignment. A combination of landslide and erosion mapping along the proposed alignment and interpretation of air photographs led to the recommendation to abandon the remainder of the alignment and adopt an alternative route, considered to be more stable. The findings were later endorsed by a detailed feasibility study and preliminary design thus supporting the cost-effective use of rapid geomorphological surveys for engineering projects in unstable mountain terrain.     

论公路建设与环境保护

从公路的设计、施工与绿化三个方面阐述了公路建设中要积极采取的有益于环境保护的措施,根据各地的自然环境、生态环境、社会经济环境等特点,因地制宜地解决好公路建设的环境保护问题,具有重要意义。     

Géologie de l'ingénieur appliquée aux études de,mise en valeur d'un site historique et de son environnement,Crète,Grèce

The paper deals with the engineering Geological studies applied to the protection and development of a historical site, the Arkadi Monastery, in Crete, (XIIth, century). The geomorphological mapping allows to point out the areas which are concerned by the problems of environmental protection—natural sites, plateaus, karstic phenomenons, gorges. Such a mapping may also be used for the protection against floods and for the design of the plateaus drainage. The geological mapping deals with, the whole area, and takes into account the lithology, the weathering, the problems concerning the earthworks and the foundations. Slope stability is presented on a separate map. The hydrological study deals with the different conditions of the area—alluvial aquifers, scattered aquifers, karstic aquifers—and proposes solutions for the water supply and for the drainage in the area—alluvial aquifers, scattered aquifers, karstic aquifers—and proposes solutions for the water supply and for the drainage in the area. A special attention is paid to the weathering of the building stones which were used for the construction of the monastery —limestones—and to the survey of similar deposits with a view to its restoration. Finally, the study deals with the seismic risks—neotectonic phenomenons, and statistical interpretation of seismic data.     

Les dépôts morainiques holocènes de la zone axiale pyrénéenne: approche déterministe de leur instabilitéà Verdun sur Ariège, (Pyrénées centrales, France)

This paper reports a study of the historic instability of the till deposits in an area of the central Pyrenees between France and Spain upslope of the town of Verdun. The object of the work was to create a model based on the geomorphological and geological mapping of landslides and a geotechnical survey of the instability of the whole of the mountainous slopes of the Domanial Verdun area. The detailed mapping allows the historic landslides to be distinguished from the more recent/active movements which involve volumes of 100,000 to 400,000?m³ of material. In addition, it was possible to assess the areal percentage of the actively slipping zones (5%) compared to the historic slide zones (12%) and the stable areas (78%). Following the European classification, two types of slides were identified in the Verdun study area: (1) historic rotational slides and (2) active translational slides located in the Verdun area at between 1000 and 1250?m altitude. The stability was calculated using the classic "method of slices", subdividing the slipped zone into vertical slices along a suitable cross section. The so-called factor of safety (F) was determined by dividing the moments of resisting forces (M_R) by the moments of driving forces (M_D). The state of limiting equilibrium has a "factor of safety" of 1. The physical parameters of the till deposits of Verdun were established as: unit weight γ=24.9?kN/m³ (calculated using the percentage of gneissic blocks contained in the tills) and porosity n=0.24. The results of 15 triaxial tests in a gravelly sand matrix were plotted in a Lambe diagram following a linear regression model [x=(σ₁+σ₃)/2 and y=(σ₁–σ₃)/2 with sin?φ′ =tan?θ]. From this the friction angle φ′=33°±3 and c′=45±5?kPa were established. The factor of safety calculated for the moraine deposits in the historic slides was 1.44 without water (Hw=0). With a height of water of 7?m, representing 85% of the till thickness, this was reduced to F=1. To achieve a factor of safety of 1.3, the maximum water level within the till should not exceed 2.5?m, representing 65% of the till thickness. Similarly, the factor of safety was calculated for the active slides of another area (shown as section 4 in Fig.?3 in the paper). Using slice number 9 from the middle of the slide, the factor of safety was 1.08 when the height of the water was taken as 90% of the till thickness. This high calculated factor of safety for the height of water is consistent with the slow movement of the actual slides. However, a lower internal cohesion of the till deposits or the presence of a weathered zone would decrease the factor of safety from 1 to 0.8. It is also possible that other parameters, such as the regional seismic activity, could have been sufficient to initiate movement (F<1) during the last 50?years. It is of note that the map of seismic activity shows that more than a 100 earthquakes with magnitudes greater than 3 have occurred in the central Pyrenees since 1660. The paper emphasises the importance of high-quality mapping which identifies and classifies areas of historic and recent instability. From this, a single geotechnical model to calculate the stability can be established. The level of the water is shown to be the critical parameter and of more significance than the variations in the effective friction angle, which itself is more important than variations in the effective cohesion. With this information it is possible to determine those areas where some form of stabilisation and/or drainage of the till deposits is necessary.     

Engineering geomorphology: A UKuk perspective

Engineering geomorphology has developed at a rather disappointingly slow rate in the UK since publication of the earlier applications in the 1970’s. Among the more notable contributions of geomorphological techniques and expertise to civil engineering have been the various landslide mapping surveys carried out for road construction projects overseas and in the UK. However, while geomorphological mapping has proved to be a useful tool for landslide assessment and the planning of geotechnical ground investigations there are four main constraints that currently limit the professional application of engineering geomorphology to civil engineering practice. First, the subject has not received universal acceptance by civil engineers who often see it as too academic and not directly applicable to engineering design. Second, when geomorphological mapping has been used it has often been applied at the beginning of a project and frequently continual geomorphological interpretation is not allowed to take place as the geotechnical ground investigation and design take place. Third the technique of geomorphological mapping is the most familiar geomorphological tool known to the civil engineer and the valid and often cost-effective contributions that geomorphologists can make to other civil engineering studies using different techniques are frequently not recognised. Finally, so-called engineering geomorphologists trained in the UK often do not have sufficient knowledge of engineering design criteria to be gainfully employed on civil engineering projects. Some of these problems may be resolved by a reconsideration of the training given to potential engineering geomorphologists in the UK, possibly by the British Geomorphological Research Group and the Engineering Group of the Geological Society, and a greater awareness among civil engineers of the full potential that engineering geomorphology can offer.     

Cliff roads: An ecological conservation technique for road construction in mountainous regions of China

Cliff ecosystems are important for biodiversity protection because these sites often support surprisingly ancient and diverse communities, including rare plants and lichens, trees, birds, and small mammals. To protect Chinese cliff ecosystems, an ancient cliff road construction technique is now being used. To understand the environmental benefits of this approach, we monitored eight cliff road sites in the warm Shennongjia region of China's Hubei Province from June 2006 to July 2009 during road construction. Compared with the traditional filling in of roadside slopes or bridge construction formerly used for highway construction in this area, the cliff highway technique, which combines cantilevered slab roads along the edge of the cliff with bridge support structures where additional support is required, reduces environmental damage and represents a good option for the conservation of fragile cliff ecosystems, while greatly reducing the construction cost. In such areas, the basic objectives of road construction must include biodiversity protection and careful control of the construction process and subsequent cleanup of the site, which cannot be ignored as a result of concentrating on the goal of using the roads to promote regional economic and tourism development.     

历史文化传承视角下的线性遗产空间保护与再利用策略研究——以梅州市古驿道活化利用为例

南粤古驿道是构成我国线性遗产网络的重要历史文化遗产,从历史文化传承的视角研究并真实再现和活化利用古驿道的物质遗产和非物质文化遗产,促进古驿道沿线地区的发展,有利于进一步丰富国内线性遗产保护与开发的理论及实践。以梅州市境内的南粤古驿道为研究对象,提出打造集传承古色、绿色、红色于一体的古驿道线性遗产空间,并采取以线串点、连线成片的"点-线-面"三位一体的空间组织策略和"规划策划-发展建设-推广宣传"的全过程活化利用方式,推动沿线地区保护传统村落、提升人居环境、发展综合旅游,实现古驿道历史、文化、生态多元价值,以期为乡村振兴战略的落地实施提供可推广的广东经验。     

A computer-aided tunneling system (CATS) aids in planning and building an urban underground reservoir project

The Hirano River underground stormwater detention reservoir was planned as a first phase of an ambitious municipal plan to prevent flooding in the southeastern district of Osaka, Japan. The reservoir has been under construction since 1981. The concept involved in the design of the reservoir is stormwater detention through temporary storage of rainwater during heavy rainfalls in order to prevent flooding in the vicinity. The underground reservoir is a 1880-m-long tunnel with a storage capacity of 140,000 m³ and a finished diameter of 10 m. The tunnel is being bored by the world's largest slurry shield (11.22-m boring diameter). This paper is primarily concerned with Phase I tunnel construction, in which the latest computer monitoring and data processing technology CATS (Computer-Aided Tunneling System) was applied to provide complete environmental protection. Some aspects of project planning are also discussed. The Phase I tunnel reservoir construction was completed on schedule, in time to prevent possible flooding of the area by intercepting 29,000 m³ (approx. 29 million l) of stormwater in 40 min when a heavy rainfall poured down on July 21, 1986.     

Estimation of source contribution to nitrate loading in road runoff using stable isotope analysis

The nitrogen load was determined in road runoff during rainfall events. Moreover, nitrate isotopes analysis was conducted to determine the contribution of nitrates from atmospheric deposition and leaching from road dust. The concentrations of NO₃-N in road runoff were higher than those in atmospheric deposits for each rainfall event, except one event with a long antecedent dry weather period. The δ¹⁸O-NO₃ in road runoff was lower than in atmospheric deposits and higher than in leachate from road dust; however, no difference in δ¹⁵N-NO₃ was observed. By using δ¹⁸O-NO₃ as an indicator for evaluating NO₃-N sources in road runoff, contribution ratios of NO₃-N from road dust were estimated to be 14–22%, 23–25%, and 22–34% for Event 1 to Event 3, respectively. These results indicated that the NO₃-N from the atmosphere accounts for more than half of the NO₃-N in road runoff.     

Reuse of waste material from decorative quartz solid surfacing in the manufacture of hot bituminous mixes

Due to the increasingly strict environmental restrictions on quarry exploitation, there are severe limitations on the use of natural aggregate for road construction. The accumulation of waste in landfills is also a pressing problem for many businesses, both from an environmental and economic perspective. This article presents the results of a research project, which studied the reuse of engineered quartz (Silestone^®) waste material as aggregate in hot bituminous mixes. After a preliminary study of the material, four bituminous mixes were manufactured, which differed in their percentage of Silestone^® waste aggregate. These mixes were applied to the surface course. Based on the highly satisfactory laboratory results obtained, the mixes were then on an actual road in Almanzora (Spain). The four mixes made from this waste material were found to meet PG-3 specifications, and consequently, were deemed suitable for road surfacing. Nevertheless, since this was the first time that this type of material has been used for this purpose, in the future it will be necessary to test the medium- and long-term mechanical behavior of the road surface.     

Mapping ground movements in open pit mining areas using differential SAR interferometry

The coherent pixel technique is an advanced differential SAR interferometry technique that has been used for mapping and monitoring ground movements in La Union mining area (Murcia, SE Spain). This technique was originally used to monitor mining subsidence in La Unión Town but unknown ground instabilities were detected in an abandoned open pit mining area nearby. Measured displacements have been analyzed with respect to geometrical and geological factors that play a role in ground movements. Then a "blind test", consisting on geomorphological mapping of detected deformed areas, was performed in order to identify the existence of unknown active processes: slope instabilities and flat accumulation areas. Finally, a detailed analysis of these results has permitted to illustrate the advantages and disadvantages of using this technique for mapping ground movements in mining areas.     

高等级公路路基边坡稳定性病害分析及防治

高等级公路路基边坡防护是防止路基病害、保证路基稳定、改善道路环境、保护生态平衡的重要措施,也直接关系到路基的外观,影响路线景观和环境协调。但是,目前多数高等级公路建设由于缺乏对防护工程的系统研究,许多工程只能借用低等级公路的防护技术,给高等级公路工程建设带来了隐患,造成了巨大的经济损失和不良的社会影响。本文讨论了高等级公路路基边坡稳定性破坏形式、产生病害的主要因素以及防治对策。确保高等级公路安全使用。     

公路建设与环境保护

通过对公路建设过程中日益突现的环境问题分析,提出了公路设计、建设、验收阶段所应采取的环境保护措施,以期实现我国公路建设和环境保护实现可持续发展的良性循环。     

越江隧道工程联络通道冻结法施工风险分析

上海复兴东路越江隧道是国内首次成功建成的双管双层隧道。由于工程规模大,工艺新颖,以及工程地质和施工环境复杂,存在很大的施工风险。本文运用风险分析方法,分析了联络通道冻结法施工中可能出现的冷冻前设备安装风险、冷冻过程中的操作风险、冷冻期间温度维持风险、拆除设备风险以及施工开挖风险。分析表明,在设计和施工上采取合理的措施后,联络通道冻结法施工的总体风险可以控制在中等风险水平,并针对联络通道冻结施工的前期、冻结施工过程、土体开挖施工和设备拆除提出了相应的防范措施。     

Construction of large cross-section double-tier Metropolitan Inter-city Highway (Ken-O-Do) Ome Tunnel by NATM

Ome Tunnel is a double-tier highway tunnel with large cross-section of 220–260 m² excavated at a shallow depth in unconsolidated ground. The tunnel was excavated by NATM. Since the tunnel passes under a road in dense residential area, surface settlement due to tunneling was restricted. Therefore, various auxiliary construction method such as long span steel pipe fore-piling with injection was adopted based on monitoring and analyzing ground behavior during construction. A total of 1060 m of tunneling work was successfully completed without major interruption of work excessive damage on surface residents and other facilities.     

基于GIS的凉水国家级自然保护区林火应急路网规划研究

摘 要：对凉水国家级自然保护区林火应急路网分析,进行优化选线,使其达到《全国森林防火规划（2016-2025）》2025年路网密度要求。运用K-means聚类算法选取道路节点,在考虑地形等环境因素下,运用ArcGIS多因素叠加分析选取整体线路,经过实地考察验证线路可行。建立林区应急道路评价体系。最终提高林区道路密度达到3.22 m/hm2,符合国家2025年期望林区道路密度。区域分割指数中的区域面积均值（``ｓ）和区域面积方差（D）分别降低了45.7%和 94.7%。为凉水保护区应急路网开设提供参考。     

Impact of fugitive emissions in ambient PM levels and composition: A case study in Southeast Spain

The results of this study show the high impact that anthropogenic fugitive emissions of mineral dust have on air quality (levels of PM₁₀, PM_2.5 and some metals) in a region in SE Spain named L'Alacantí. This could be extensive to other areas of Europe with similar characteristics. Fugitive emissions, such as those arising from large public construction works, cement and ceramic manufacturing, mining, heavy industries, handling and transport of powdered raw materials and road dust, are very often left out of emission monitoring and inspections in Europe. The comparative study of daily PM₁₀ series in the area shows how the increase of annual average PM₁₀ concentrations over 40 μg/m³ is due to extreme episodes occurring in 2006 and 2007, at a regional scale, given the simultaneous recording of PM episodes at distant monitoring sites. The annual average values of the PM₁₀ concentrations were close to or slightly higher than 40 μg/m³ (limit value of Directive 2008/50/CE) during 2006–2007 (Alicante-University 39–41, Agost 40–42, Sant Vicent 42–46, Alicante-El Plà 40–42 μg/m³). The main PM₁₀ sources in the zone were identified with the assistance of the PMF receptor model. Six common factors were determined, mineral as a main source (37% at Agost and 32% at Sant Vicent), road traffic, secondary sulfate, petroleum coke, sea spray and industry. Mineralogical studies, with XRD and SEM-EDX techniques, support the hypothesis that the highest PM episodes are associated to fugitive emissions of mineral matter. Despite the fact that L'Alacantí region is a heavily industrialized area with two cement plants and a significant number of ceramic manufacturing plants, the fugitive emissions may have accounted for the exceedances of the PM limit values during these two years, part of them caused by the construction of a highway. These results may contribute to the interpretation of prior studies on source apportionment carried out in Southern Europe, with very high loads of anthropogenic dust in PM₁₀ and PM_2.5.     

跨和平大道施工安全防护设计

对武汉天兴洲公铁两用长江大桥公路引线工程主线桥跨和平大道施工安全防护进行了分析,在该工程施工中通过防护膺架、交通安全措施等工程措施,实现了跨和平大道主线桥的安全施工,为今后类似工程的施工防护设计提供了示范。