深孔预裂爆破技术在泽城水电站溢洪道边坡开挖中的应用

山西泽城水电站溢洪道工程,石方开挖量约149万m^3,其工期紧、开挖强度大、边坡质量要求高。为确保边坡稳定,加快施工进度,采用了深孔预裂爆破技术。文中介绍了边坡深孔预裂爆破的技术参数、施工方法、起爆技术及爆破效果。     

小孔径超深孔预裂爆破在天生桥一级电站进水塔高边坡开挖中的运用

根据天生桥一级电站进水塔高边坡具体开挖特点进行分析，大胆采用小孔径超深孔预裂爆破，使20m高垂直边坡一次预裂成型，取得了理想的工程爆破效果，为今后类似爆破工程提供了实践经验。     

深孔预裂梯段爆破在喜儿沟水电站高边坡开挖中的应用

本文重点介绍了甘肃喜儿沟水电站首部枢纽进水口高边坡开挖中运用的深孔预裂梯段爆破技术,结合工程实际选择合适的爆破参数、装药结构、起爆网络等,有效控制了坡面平整及超欠挖, .并降低了爆破所造成的地震、飞石、冲击波等危害,达到了预期的爆破效果.     

小孔径超深孔预裂爆破在天生桥一级电站进水塔高边坡开挖中的运用

根据天生桥一级电站进水塔高边坡具体开挖特点进行分析，大胆采用小孔径超深孔预裂爆破，使20m高垂直边坡一次预裂成型，取得了理想的工程爆破效果，为今后类似爆破工程提供了实践经验。     

观音阁工程高边坡开挖中的预裂爆破技术

观音阁水库采用碾压混凝土重力坝型，其中 1～ 4号坝段镶嵌在高边坡上，设计采取阶梯开挖，开挖中采用了边线预裂爆破技术。文中主要论述了预裂爆破技术及其施工情况。     

察汗乌苏水电站高边坡深孔预裂爆破开挖技术

察汗乌苏水电站进水口高边坡开挖高度最大为140 m,工程质量与进度要求非常高.采用深孔预裂爆破技术,对边坡坡度1:0.4、垂直高度为20 m的梯段,一次性开挖爆破,可减少爆破梯段层数,减少机械设备避炮转运时间,有利于组织一次较大规模的爆破,对加快施工进度大有好处,同时可减少预裂面中部错台,使边坡坡度达到设计要求,有利于边坡稳定. 最终的检测结果表明:预裂孔残孔率达到75%,局部完整率85%以上,完全达到设计要求.     

预裂爆破技术在溢洪道出口消力池石方开挖中的应用

预裂爆破技术是水利水电工程岩石施工中广泛采用的一项先进技术,近年来广大技术工作者对预裂爆破的机理和应用进行了深入研究,取得了丰硕的成果。溢洪道在开挖施工中,通过精心组织和施工实践,取得了预裂爆破施工的成功经验。通过对该项技术进行总结,意图为同类工程高边坡深孔预裂爆破技术的应用及其施工质量控制提供参考,以促进预裂爆破施工水平的提高。     

水口水电站竖直高边坡开挖

水口水电站土石开挖总方量高达800多万m~3;它主要是采用竖直高边坡配以少量的边坡锚杆支护法进行岩石开挖的。在短短的两年时问里,即完成了导流明渠400多万m~3的土石开挖任务,这是加强施工管理,运用先进爆破技术——预裂爆破和深孔梯段爆破技术,并采用大型先进机械设备取得的成果。本文总结分析了在水口这样的花岗岩地区预裂爆破参数的选定,预裂爆破施工以及取得的成功经验和存在的问题;并对深孔梯段爆破法通过典型实例,说明在水口工程中发挥的作用。     

塘坝边坡开挖中的爆破设计与施工

2022年冬奥会延庆赛区A部分场馆配套基础设施——造雪引水系统工程施工项目位于北京市延庆区张山营镇小海坨山地区。针对1 050 m高程塘坝边坡两岸山体岩性以燕山晚期侵入花岗岩为主的情况,故采用爆破形式进行开挖。对开挖过程中采用的预裂爆破、深孔梯段爆破、浅孔爆破进行设计,同时对相应的施工方法进行介绍,旨在为后续遇到同类问题提供参考。     

三板溪水电站进水口高边坡开挖

介绍预裂爆破技术在三板溪水电站进水口高边坡开挖中的应用,对施工中遇到的问题作了相应分析,提出了提高爆破效果的技术措施。     

Call for Papers

正As the eldest and most distributed professional journal of water industry,Water Wastewater Engineering(W WE)gained very wide acceptance from the colleagues working in this field in this country since start publication in 1964.Now it is administrated by the Ministry of Construction of the People’s Republic of China and sponsored by the China Civil Engineering Society etc.     

地下厂房施工过程的三维非线性数值模拟分析

根据冗各电站地下厂房开挖支护的施工顺序,以隐式杆单元模拟锚杆,以壳单元模拟混凝土喷层,采用三维非线性有限元技术,对洞室群的开挖支护动态过程进行了模拟计算。通过三维非线性有限元计算分析得到:洞室群动态开挖过程中围岩应力变形的分布规律,围岩塑性区的发展规律,锚杆受力变化情况。计算结果表明:整个开挖过程中,洞周围岩位移变化规律正常,量值较小,塑性区主要分布在洞室周边,围岩稳定性较好;但在洞室交叉口处围岩的变形较大,出现较大范围的塑性区,在此基础上提出了支护措施优化方案,并对优化方案的效果进行了评价。     

Serial discontinuities in a Rocky mountain river. I. Distribution and abundance of plecoptera

Samples were taken year-round at eleven sites along the altitudinal profile (2900-1400 m a.s.l.) of the Gunnison River, a 329 km tributary of the Colorado River, to document the distribution of the Plecoptera and to evaluate responses to hypolimnial-release dams in the headwaters and middle reaches. Twenty-two species were present, with the greatest species richness occurring in an unregulated segment upstream of the middle reach dams; average nymphal biomass over the study period (175 organisms, 395 mg dry mass m^?2) was also greatest in this segment. Only four species (58 organisms, 48 mg m^?2) were present in the tailwaters of the headwater dam and values were greatly reduced (nine species; 35 organisms, 180 mg m^?2) below the middle reach dams. The stonefly community recovered ca. 80 km downstream from the last dam (15 species; 244 organisms, 250 mg m^?2), apparently in response to natural resetting of environmental conditions corresponding to those above the middle reach dams. At the most downstream site (11) only four species (four organisms, 16 mg m^?2) were present. The observed distributional pattern is a classic serial discontinuity in response to hypolimnial stream regulation in a temperate latitude river.     

Evaluation of freshwater mussel relocation as a conservation and management strategy

The relocation of unionacean mussels is commonly used as a conservation and management tool in large rivers and streams. Relocation has been used to recolonize areas where mussel populations have been eliminated by prior pollution events, to remove mussels from construction zones and to re-establish populations of endangered species. More recently, relocation has been used to protect native freshwater mussels from colonization by the exotic zebra mussel Dreissena polymorpha. We conducted a literature review of mussel relocations and evaluated their relative success as a conservation and management strategy. We found that 43% of all relocations were conducted because of construction projects that were forced to comply with the Endangered Species Act 1973 and that only 16% were monitored for five or more consecutive years. Most (43%) relocation projects were conducted from July to September, presumably a period when reproductive stress is relatively low for most species and the metabolic rate is sufficient for reburrowing in the substrate. The mortality of relocated mussels was unreported in 27% of projects; reported mortality varied widely among projects and species and was difficult to assess. The mean mortality of relocated mussels was 49% based on an average recovery rate of 43%. There is little guidance on the methods for relocation or for monitoring the subsequent long-term status of relocated mussels. Based on this evaluation, research is needed to develop criteria for selecting a suitable relocation site and to establish appropriate methods and guidelines for conducting relocation projects.     

Impacts of Microcystis on algal biodiversity and use of new technology to remove Microcystis and dissolved nutrients

Cyanobacteria often dominate eutrophic lakes, outcompeting green algae that are required by fish and zooplankton. This study was undertaken to ascertain the impact of the cyanobacterium, Microcystis, on algal biodiversity. Under laboratory conditions, we found that the presence of Microcystis decreased phyla richness by 58%, phyla evenness by 47%, genera richness by 66% and genera evenness by 51%. Analysis by mixed anova s demonstrated a significant interaction between treatment and time and confirmed a significant reduction in richness and evenness of phyla and genera. We also conducted a phosphate restriction assay on the algae in Mason Lake (Irvine, CA, USA) and found that the threshold needed for algal growth there was 0.02 mg L^?1 PO₄. A pilot study was then conducted to test the effectiveness of the Blue Pro? water treatment facility in removal of this colonial organism from Mason Lake, in addition to removal of dissolved nutrients required for its growth. We measured a 97% reduction in Microcystis cells, a 72% reduction in chlorophyll‐a, and a 96% reduction in phosphate after just one 10 min cycle through the unit. Our study demonstrated that removal of Microcystis colonies may allow green algae to increase in numbers. This may improve algal biodiversity, which will benefit zooplankton and fishes.     

基于模型试验的河床砂砾石层基本特性研究

为了经济可靠地确定深厚覆盖层的基本特性参数,以大渡河双江口水电站坝基河床砂砾石层基本特性研究为工程背景,进行大尺寸模型试验,研究河床砂砾石层的旁压模量和动探击数随密度、级配以及上覆压力的变化规律。根据室内模型试验结果,结合现场旁压试验及钻孔试验成果,推断出坝址区河床砂砾石相关层位的密度,并依此进行砂砾石室内力学试验,获得设计所需力学参数。研究成果可为深厚覆盖层基本特性测试提供新的方法。     

库水波动下库岸边坡地下水浸润线解析解及误差分析

解析法是库岸边坡地下水浸润线计算中便于实际应用的方法,但该方法须基于若干假定并对潜水运动基本方程线性化后才能求解。针对各假定和线性化过程建立不同的地下水渗流数学模型,用解析法和有限元法解答上述数学模型,分析各误差大小及其规律。结果表明：库岸垂直处理带来的误差要小于方程线性化处理和不考虑非饱和渗流带来的误差,而且它们都随渗透系数变大而减小;在三峡库区库水调度情况下,假定库水位等速变化带来的误差对大多岸坡而言可以忽略;计算库岸边坡地下水浸润线时,解析法只适用于水位变化幅度相比含水层厚度较小,且几何边界规则、岩土结构简单、岩土体渗透性较好时的情况。     

SPATIAL AND TEMPORAL WATER QUALITY VARIABILITY IN AQUATIC HABITATS OF A CULTIVATED FLOODPLAIN

The floodplains of lowland rivers contain diverse aquatic habitats that provide valuable ecosystem services but are perturbed when intensively cultivated. Hydrologic, water chemistry and biological (fish) conditions in five aquatic habitats along the Coldwater River, Mississippi, were measured for more than 4 years: the river, two severed meanders that functioned as backwaters, a managed wetland and an ephemeral channel draining cultivated fields. Off‐channel habitats were connected to downstream regions 0.10% to 32% of the dry season and 24% to 67% of the wet season. The median temperatures for the five monitored sites ranged from 18°C to 23°C, the median total solids concentration for all sites was 135 mg L^?1, the median total phosphorus was 0.29 mg L^?1 and the median total nitrogen was 1.56 mg L^?1. Chemical and physical water quality displayed strong seasonal differences between the wet winter/spring and the dry summer/fall periods so that temporal variation consisted of gradual seasonal trends superimposed on strong diurnal variations. All off‐channel habitats exhibited periods of hypoxia and temperatures >30°C during the dry season. Between‐site gradients of water and habitat quality were strongly coupled to water depth and runoff loading. The rehabilitation of one backwater by increasing water depth and diverting agricultural runoff was associated with improved water quality and fish species richness relative to an adjacent untreated backwater. The diversion of polluted runoff and the use of water control structures to maintain greater water depth were observed to be effective management tools, but the former reduces the water supply to habitats that tend to dry up and the latter reduces connectivity. Published in 2011 by John Wiley & Sons, Ltd.     

簸箕李引黄灌区水沙分布及优化调度的经验

灌区利用水沙观测所取得的资料和试验数据，运用水沙运动力学理论，总结分析和揭示了灌区水沙分布的规律和特点。在此基础上，结合灌区的实际运行情况，围绕减少骨干渠道的淤积进行探讨、研究，进而，优化水沙调度方案。该方案实施后，骨干渠道减旅伴效果明显，取得了成功的经验。     

小湾水库大坝防渗面板及其裂缝的加固处理

小湾水库大坝防渗面板整体抗渗性能差,且存在多条裂缝,通过对面板钢丝网喷涂丙乳砂浆加固处理及其裂缝修补,大坝渗漏量明显减少,且左岸上灌浆廊道内及大坝下游坝面92～93 m高程下廊道入口处原有小股射流全部消失.