我国大型岩土工程施工安全风险管理研究进展

在我国,以城市轨道交通、高速公路网建设、高速铁路网建设、重大水利工程建设等为代表的大型岩土工程具有尺度大、施工周期长、操作复杂和工程安全状况堪忧的特点。不同类型的安全事故持续不断,造成的经济损失和人员伤亡居高不下。概括总结了2010－2017年间我国大型岩土工程施工安全风险管理研究方面的主要进展,包括：（1）大型岩土工程施工安全风险管理重大科技项目、成果奖励、规范;（2）大型岩土工程施工安全风险分析与评估方法方面研究进展;（3）大型岩土工程施工安全风险监控与预警方面研究进展;（4）大型岩土工程施工安全风险管理信息化技术与平台方面研究进展;（5）大型岩土工程施工安全风险智能化分析与控制方面研究进展。基于我国大型岩土工程施工安全风险管理研究方面主要进展的分析,提出了我国大型岩土工程施工安全风险管理方面面临的新挑战：（1）定量化风险评估理论和技术的应用推广;（2）风险决策理论;（3）推行全过程安全风险管理计划;（4）构建岩土工程安全事故案例共享平台;（5）基于大数据挖掘技术的岩土工程参数分析与控制;（6）智慧岩土工程研究和建设。     

基于应变软化的岩土工程单元安全度评价方法研究

针对大多已有岩土工程局部安全评价方法未考虑拉伸破坏和屈服、破坏阶段的问题,对围岩的局部安全评价方法进行了相应的改进。基于Mohr-Coulomb屈服准则和应变软化模型建立了单元安全度的评价方法和新的定义,综合考虑剪切和拉伸破坏模式,定义一个统一的变量ZSD来表征和量化岩土体单元从弹性、屈服到破坏的安全程度,实现复杂应力状态下岩土体渐进破坏过程的局部安全性定量评价。推导了ZSD的各阶段表达公式,利用FISH语言在FLAC3D平台编写程序。通过相应的实例和工程进行了ZSD计算,验证了该方法的正确性与有效性。该方法具有参数表达简单,易于在程序中实现,可通过ZSD所在值域判断单元所处的状态,可直观揭示岩土体渐进破坏过程等诸多优点。该方法为分析和预测岩土工程中危险区域的演化和描述渐进破坏过程提供了有效的手段。      

海底管道出露悬空环境风险的定量评价研究

海底管道是海洋油气输送的主要方式,其运行状况直接关系到海上油气田的安全和海洋生态环境的质量。本文先以海底管道出露悬空作为故障树的顶事件,分析出海洋环境中各项基本事件,构建针对海洋环境的海底管道故障树模型;再以灰色模糊识别为理论基础,量化对海底管道安全有影响的海洋环境因素,并以层次分析法对每个风险因素进行分级赋权,确定评价指标范围和权重,进而构建海洋环境条件的海底管道风险评价体系。利用该体系对平湖油气田海底管道4个区段进行环境风险评价,避免了将整段管道一同评价导致的信息均等化,评价结果不能真实反映风险等级高的区段的情况;评价结果与管道2014~2016年现场检测数据对比,两者均显示P2分区中海底管道的风险等级较高,说明了该模型具有一定的合理性和实用性。     

New insights into the carbonate karstic fault system and reservoir formation in the Southern Tahe area of the Tarim Basin

As worldwide hydrocarbon exploration has extended from shallowly to deeply buried strata, reservoir quality has attracted substantial and persistent interest in petroleum geology. In particular, deeply buried strata (>5500 m) in the Tarim Basin have attracted considerable attention because carbonate reservoirs that have experienced fracture or dissolution have also been shown to demonstrate considerable hydrocarbon potential. Therefore, it is necessary to determine how these reservoirs are developed and distributed in detail from both scientific and practical standpoints.In this paper, we address this issue using a case study in the southern Tahe area, which is contained within the largest Palaeozoic marine oilfield in China. In the northern Tahe area, mega-paleokarst systems developed in the Ordovician strata; however, the reservoir quality in the southern part of the Tahe area is relatively poor because it is covered by insoluble formations during karstification. Observations of cores and analyses of images of well logging demonstrate that these reservoirs are dominated by caves, vugs and fractures that have developed near faults. We speculate that the faults penetrating insoluble formations represent the main dissolution passages that originally developed these karstic fault systems. Additionally, we analyse a series of outcrops, seismic data, and structures to characterize the spatial geometry of these major faults and their surrounding fractures in detail. Most of these are strike-slip faults, and their subsequent reservoirs can be divided into three categories based on their development, including dendritic, sandwich and slab reservoirs. Recent studies demonstrate that karstic fault reservoirs are most common traps in the study area. Although various types of carbonate karstic fault reservoirs are represented in this region, the dendritic karstic fault reservoir is the most hydrocarbon-rich.Guided by these initial results, 108 wells were drilled from 2013 to 2014, producing 485 thousand tons of oil and yielding success ratios greater than 89%. The average production of dendritic reservoirs is 37.4 tons per day (t/d), while those of sandwich and slab types are 20.2 t/d and 14.0 t/d, respectively. These results represent significant references for future hydrocarbon exploration and the development of similar deeply buried karstic fault reservoirs in the Tarim Basin and elsewhere.     

系缆损伤对绷紧式系泊系统动力响应的影响

探究合成纤维系缆损伤对绷紧式系泊系统响应的影响,具有重要的工程意义。通过高强聚乙烯(HMPE)缆绳损伤动刚度实验,获得其动刚度随损伤的演变规律。在数值计算上,借鉴并合理简化了前人提出的动刚度经验公式,通过处理实验结果确定动刚度经验公式的参数并进行验证。在此基础上,以一座采用高强聚乙烯缆绳为主体系缆的FPSO为例,将所得动刚度经验公式导入系泊分析软件,结合水动力分析,计算得到在相同海洋环境中,系缆发生不同程度损伤时,各系缆张力和平台偏移响应的结果。通过处理、分析所得的计算结果,获得合成纤维缆绳损伤演变对绷紧式系泊系统响应的影响规律,并据此为系缆更换提供了建议。这些成果既有利于把握绷紧式系泊系统的非线性动力响应,也对安全、经济、合理地运用合成纤维系缆具有重要意义。     

基于主成分分析的甘肃省水资源承载力评价

以甘肃省水资源承载力为研究对象,运用主成分分析法对甘肃省水资源承载力从时间和空间两个角度进行了综合评价。研究表明：影响水资源承载力的因子主要包括经济发展因子、人口因子、水资源供需平衡因子、农业生产用水因子;2006-2015年,甘肃省水资源承载力整体呈现下降趋势;甘肃省水资源承载力存在显著的地区差异,甘南等地区水资源承载力较大,白银等地区居中,张掖等地区较小,兰州等地区最小,这主要是受水资源供需不平衡、农业生产用水差异较大和经济发展及人口因素的影响。     

The Implementation Effects of a Nationwide Sloping Farmland Soil Erosion Control Project in China

To understand implementation of a nationwide sloping farmland soil erosion comprehensive control project during China’s 12^th Five-Year Plan we used data collection and expert consultation. We selected 24 indexes across three aspects including project management, engineering construction and implementation benefit and used AHP-grey correlation analysis methods. We found that the scores for engineering construction were greater than 0.65 in most of the provinces, autonomous regions and municipalities. These scores are high and scores for project management and implementation benefit are between 0.45-0.65; however, overall scores are low. The comprehensive evaluation results are normally distributed. The composite scores for Sichuan, Yunnan and Guizhou are 0.71, 0.68 and 0.68 respectively, indicating that the implementation effects are good. The scores for Jilin and Liaoning are 0.38 and 0.42 respectively, indicating that the implementation effects need improvement. Scores for other provinces are between 0.45-0.65 and the effects are medium. The evaluation results show certain zonal rules spatially and the implementation effect in karst regions of Southwest China is the highest, followed by the purple soil region in Southwest China, Loess Plateau region of Northwest China, earth-rock mountain region of North China and red soil hilly region of South China. The implementation effect in the black soil region of Northeast China suggests that improvement is needed in this region.     

Overview of Ecological Restoration Technologies and Evaluation Systems

Ecological degradation is a global problem, and ecological restoration technologies have played and will continue to play an important role in its mitigation. However, the lack of systematic research and evaluations of ecological technologies has thus far affected their effective application in vulnerable ecological regions. This study therefore provides an overview of the main technologies for remediating soil and water erosion, desertification, and rock desertification in China and throughout the world. It addresses key issues and recommends approaches for evaluating ecological restoration technologies. Restoration technology emerged as early as 1800. Over the years such technology has changed from single objective applications to multi-purpose, multi-objective applications employing strategies that take into account ecosystem rehabilitation and integrated ecological and socioeconomic development. Along with this technological evolution, different countries have taken pertinent actions as part of their restoration initiatives. However, key issues remain, including the lack of location-specific restoration technologies and a methodological strategy to assess and prioritize existing technologies. This study proposes a four-level analytical hierarchical framework in conjunction with an indicator system that highlights the establishment and adaptation of associative indicators, while also recommending a three-phase evaluation method (TheMert), targeting TheMert to qualitative (quick and extensive) and quantitative (detailed) evaluations in order to select the most appropriate restoration technologies available. This study can also be used as a basis for understanding the evaluation and prioritization of restoration technologies, while increasing the awareness of decision makers and the public on the role of technology in restoring degraded ecosystems.     

Influence of Ecological Technology Measures on the Annual Sediment Load of the Wuding River

The influence of ecological technology measures on the annual sediment loads of rivers complies with the principles of statistics. In this paper, the annual sediment load of the Wuding River is taken as the dependent variable and the rainfall, rainstorms during the flood period of the Wuding River and areas of ecological technology measures are taken as the independent variables to analyze the influence of ecological technology measures on the annual sediment load of the Wuding River during the years 1956 to 2007. This research uses a stepwise regression method. The result shows that 1) the non-linear regression equation composed of three independent variables including 7-8 monthly rainfalls along the Wuding River, areas of ecological technology measures and maximum daily rainfall along the Wuding River has been calculated and set up; the correlation coefficient is R²=0.857 and the significance level is α=0.001. 2) R²=0.717 is adjusted and the regression equation reveals a change of annual sediment load exceeding 71.7% over 52 years; 3) The standardized regression coefficient for ecological technology measure area has the maximum absolute value of the three independent variables shows maximum influence on the change of annual sediment load; and 4) Because of implementing the ecological technology measures, until to year of 2007, when the 7-8 monthly rainfall and maximum daily rainfall are the maximum values in the research section, the annual sediment load is calculated as 149million ton, which is 36% of the maximum value in the history.     

湖南省饮用天然矿泉水资源潜力评价与开发利用区划

湖南省饮用天然矿泉水资源丰富、水质优良.本文从区域地质条件、水文地质条件以及矿泉水资源现状几个方面来选取评价因子,利用层次分析法构建评价指标体系,运用综合指数评价模型对湖南省饮用天然矿泉水资源潜力进行评价,最后根据评价结果划分了石门-慈利、张家界-永顺、绥宁等11个矿泉水资源高潜力区,石门-花垣等14个矿泉水资源较高潜力区,以及中等潜力区和低潜力区.此外基于资源潜力评价结果,结合市场潜力和开发利用经济技术条件两个方面,最后将全省区划为张家界-永顺矿泉水分布区、益阳-韶山-湘潭等4个矿泉水优先开发保护区,石门-慈利、隆回、绥宁等12个矿泉水重点开发保护区,以及远景开发保护区和限制开发保护区.