掺砾料心墙砾石土压实性能研究

两河口水电站大坝为295m高心墙堆石坝,土料来源分散,均一性差,颗粒偏细,需掺砾改性。心墙填筑质量直接关系到整个坝体的安全运行,针对设计提出填筑质量采用全料压实度和细料压实度双控等多项质量控制参数,围绕土料的使用及填筑质量控制标准的确定,通过系列试验研究,提出了掺砾心墙砾石土随掺砾量变化的击实特性及细料压实度范围值,为设计确定控制参数提供依据。     

压实度控制在“635”主坝施工中的应用

在土石坝施工中，如何合理、有效地控制粘土心墙填筑质量是确保坝体填筑质量的关键。以往的施工中，主要以干密度为控制指标，这种控制方法不能很好反映土料压实性的变化，尤其对土料性质变化较大的土料控制缺乏合理性。近年来以压实度作为填筑质量控制指标的方法，已逐渐普及。     

压实度控制在“635”主坝施工中的应用

在土石坝施工中，如何合理、有效地控制粘土心墙填筑质量是确保坝体填筑质量的着急２。以往擅长或，主要以干密度为控制指标，这种控制不能很好反映土料压实性的变化，尤其对土料性质变化较大的土料控制缺乏合理性。近年来以压实度作为填筑质量控制指标的方法，已逐渐普及。     

瀑布沟水电站砾石土心墙料碾压试验研究

瀑布沟水电站心墙堆石坝采用砾石土心墙防渗料,为了确定心墙料达到设计填筑压实标准经济合理的施工参数,在大坝填筑前对砾石土料及其与粘土掺合料的渗透、压实特性以及坝体心墙料填筑施工质量控制的快速检测方法等进行了试验研究,针对土料特性,提出了适宜的碾压方案及质量控制的快速检测方法.     

苗尾水电站心墙防渗土料压实质量检测方法及控制标准

高土质心墙堆石坝采用砾质土作为心墙防渗料已成为发展趋势,砾质土的压实质量是施工控制的重点。目前常用于大坝防渗料填筑施工压实效果检测的几种控制方法的对比分析表明,采用三点击实法检测粒径小于20mm细料的压实度作为控制标准,全料的压实度作为复核标准是合适的。用优选的压实度检测方法对苗尾水电站防渗土料进行了碾压试验,并提出了其压实度控制标准的建议。     

满拉水利枢纽拦河坝宽级配心墙土料填筑压实度控制

满拉水利枢纽心墙土料填筑施工中，由于特殊的地质构造，形成坝体填筑宽级配心墙土料，施工中4208．00m高程以上改用压实度控制土料填筑质量，采用三点击实法控制心墙填筑压实度。4208．00－4260．30m高程共进行夯实度检测410组，平均压实度0．999，最大值1．066，最小值0．916，达到设计控制指标0．98的占92．2％，合格率100％。实践表明，采用压实度控制防渗心墙宽级配与土料填筑质量是行之有效的。     

采用砾质粘土填筑堆石坝心墙初探

开挖料一般含风化碎(砾)石,细料含量较低,均一性不佳,能否用作中高土石坝防渗土料,取决于其在压实过程中的颗粒破碎程度和对级配的改善程度,文章对含碎(砾)质的开挖粘土料进行系列试验研究,对比分析了含碎(砾)质的开挖粘土料和掺加粉质粘土土料的压实特性和颗粒破碎规律,同时提出了利用含碎(砾)石土料填筑防渗心墙的实际施工中的要求和措施。     

糯扎渡水电站粘土心墙压实度检测方法及控制标准

分析了堆石坝心墙掺砾土料填筑体全料压实度最大干密度移动平均值检测法及大型击实检测法的缺陷。结合糯扎渡水电站砾质土料的实际情况,提出了用粒径小于20 mm的细料进行三点击实以快速检测填筑体压实度的方法。与直接检测全料压实度指标的方法相比,细料三点击实快速检测法简捷实用且准确度高。最后,对砾质粘土心墙填筑体压实度指标的检测控制标准提出了具体建议。     

土石坝心墙掺砾土的渗透特性冻融演化规律试验研究

高土石坝普遍采用掺砾黏土作为心墙区的压实填筑材料,而高寒区土石坝心墙在施工过程中面临严峻的冻融问题.对经历冻融作用后的压实掺砾黏土料开展一系列三轴渗透试验,研究冻融条件下其渗透特性的演化规律.试验结果表明:冻融作用后,掺砾黏土的渗透系数较未冻融时增大,且增加程度受冻融次数、围压、掺砾量和初始含水率等因素影响.随着冻融次...     

糯扎渡水电站掺砾土击实特性及填筑质量检测方法研究

糯扎渡水电站防渗心墙土料采用由土料场开采的混合土料掺入人工碎石组成的掺砾土料,大规模采用人工掺砾技术在国内属首次。在对掺砾土进行一系列击实试验研究以获得掺砾土的击实特性的基础上,进一步研究了全料压实度预控线法及细料(<20 mm)压实度控制法两种质量检测方法。结果表明,现场使用细料三点击实法进行掺砾土填筑质量检测具有高效、结果可靠等优点。     

Tastes associated with products in contact with drinking water.

Over the past 9 years the Australian Water Quality Centre (AWQC) has conducted testing in accordance with Australian and New Zealand Standard AS/NZS 4020--"Products for use in contact with drinking water" (1999). A test included as part of this standard is taste of water extracts. This test assesses the ability of products to impart discernible taste to drinking water using panellists trained in accordance with Standard Methods for the Examination of Water and Wastewater--Flavour Profile Analysis 2170 B (1999). Over 1000 products from companies worldwide, have been assessed at the AWQC in accordance with AS/NZS 4020 including pipes, valves, tap fittings and numerous other products used in contact with water. The products must not impart any discernible taste to obtain compliance and be deemed suitable for use in contact with drinking water. This study compiles the products assessed and the types of tastes obtained from both chlorinated and non-chlorinated extracts. In particular the study focuses on taste associated with polyethylene pipes, coatings and valves, which in some instances have been problematic. Analysis revealed that most taste problems occur when chlorinated water has been used in extraction experiments and this is in line with consumer complaints regarding taste imparted by plumbing products. The collation of this data provides a valuable assessment for manufacturers, the water industry and consumers.     

大尺度水文模型及其与气候模型的联结耦合研究

本文综述陆地表面水文过程，大尺度水文模型及其与气候模型联结耦合研究的最新进展和存在问题。介绍ＧＥＷＥＸ－ＧＡＭＥ研究项目的目标和内容，科学价值和现实意义及其在我国开展研究的计划。     

不同改性膨润土处理染料废水的实践

钙基膨润土经不同的改性,可用来处理染料废水.分析比较了不同改性后的膨润土处理染料废水的效果.处理效果由强到弱,依次是柱撑酸化膨润土、柱撑膨润土、酸化膨润土、酸化柱撑膨润土、钠化膨润土、钙基膨润土.     

Hydrological daily rainfall-runoff simulation with BTOPMC model and comparison with Xin'anjiang model

A grid-based distributed hydrological model, the Block-wise use of TOPMODEL (BTOPMC), which was developed from the original TOPMODEL, was used for hydrological daily rainfall-runoff simulation. In the BTOPMC model, the runoff is explicitly calculated on a cell-by-cell basis, and the Muskingum-Cunge flow concentration method is used. In order to test the model's applicability, the BTOPMC model and the Xin'anjiang model were applied to the simulation of a humid watershed and a semi-humid to semi-arid watershed in China. The model parameters were optimized with the Shuffle Complex Evolution (SCE-UA) method. Results show that both models can effectively simulate the daily hydrograph in humid watersheds, but that the BTOPMC model performs poorly in semi-humid to semi-arid watersheds. The excess-infiltration mechanism should be incorporated into the BTOPMC model to broaden the model's applicability.     

Coping with Hydrological Extremes

Abstract

Coping with hydrological extremes, floods, and droughts has been a major concern since the dawn of human civilization. Freshwater, a necessary condition of life and a raw material used in very high volumes in virtually every human activity, is becoming increasingly scarce. Water use has risen considerably in the last hundred years at a pace exceeding the population growth. Therefore, societies are increasingly vulnerable to droughts and water deficits. Although the 21st century is heralded as the age of water scarcity, flood losses continue to grow. Increasing global vulnerability results to a large extent from soaring anthropopressure: settlements in hazardous locations and adverse land use changes. Deforestation and urbanization lead to reduction of the storage volume and higher values of runoff coefficient. In more wealthy countries, it is the material flood losses that continue to grow, while the number of fatalities goes down. Advanced flood preparedness systems can save lives and reduce human suffering. In some regions of the world, long-term forecasts (e.g., ENSO) help improve the preparedness for hydrological extremes, both floods and droughts, and hopefully will even more so in the future. Scenarios for future climate indicate the possibility of sharpening the extremes and changes of their seasonality. For instance, in Western Scotland and Norway, an increase of winter floods has already been observed. According to recent assessments, there is a growing risk of summer droughts in the Mediterranean region: less precipitation in summer and higher temperature will coincide, causing higher evapo-transpiration and less runoff. Fighting with floods and droughts has not been quite successful. Humans have to get used to the fact that extreme hydrological events are natural phenomena that will continue to occur. While doing one's best to improve the preparedness systems, it is necessary to learn to live with hydrological extremes.     

Spillway with nappe aeration

Conclusion Investigations showed that aeration of the flow by jump-off aerators is a simple, reliable, and economic means of protecting the overflow surface against cavitation erosion or suppressing it on an operating structure. Flow aeration can be regulated by the size of the jump-off aerators and change of the capacity of the air-supply system. Translated from Gidrotekhnicheskoe Stroitel'stvo, No. 5, pp. 16–20, May, 1973.     

只以今生续画缘

此生能够画画并以此为业,可算是与画有缘。对画画感兴趣可能是大多孩子的爱好。余少时亦能在乡贤教诲下描摹动物、鞍马、人物,那也只不过是一种儿时的游戏。延伸下来慢慢地竟成了养家糊口安身立命的职业,可以说这真的是一种幸运,可谓与画有缘。