Effect of connecting rain barrels on the storage size reduction

In this article, the possibility of sharing rain barrels and the potential benefit of reducing storage size through physical and non‐physical connections of rain barrels in a community are investigated. Using the concepts of homogeneous/heterogeneous users in rainwater harvesting systems (RWHS), two simple cases of a community composed of four prospective users are examined. The first is performed with the users who have the same mean and variance in water demands (homogeneous users), and the second is with the users with different means and variances (heterogeneous users). To take account for the rainfall characteristics in different places, historical records from six cities in the USA are used for storage–reliability–yield analysis. The result indicates that required total storage can be reduced by connecting multiple rain barrels. In addition, a significant difference is found between homogeneous and heterogeneous user groups. Homogeneous users do not achieve a substantial benefit from connecting their rain barrels; these users may even be disadvantaged by sharing. In contrast, heterogeneous users receive benefit by reducing the total required storage. Most benefit is expected between users with maximum difference in mean water demands. The reduction in storage size was as considerable as 37% in this study. The quantity of storage reduction depends on locations and target reliabilities. Knowledge of the benefits and limitations of rain barrel connections can improve RWHS performance through ability to customize a network plan for individual users. Copyright © 2011 John Wiley & Sons, Ltd.     

生石灰桩及水泥注浆法在地基加固纠偏中的应用

某礼堂综合楼受浸水损坏，采用生石灰桩及高压水泥注浆综合法加固建筑物沉陷部分地基，获得成功。     

ANALYSIS ON MOUTH BAR EVOLUTION OF THE YELLOW RIVER ESTUARY

ＡＮＡＬＹＳＩＳＯＮＭＯＵＴＨＢＡＲＥＶＯＬＵＴＩＯＮＯＦＴＨＥＹＥＬＬＯＷＲＩＶＥＲＥＳＴＵＡＲＹＪＩＺｕｗｅｎ；ＨＵＣｈｕｎｈｏｎｇ（Ｅｎｇｉｎｅｅｒ，ＤｅｐａｒｔｍｅｎｔｏｆＳｅｄｉｍｅｎｔａｔｉｏｎＥｎｇｉｎｅｅｒｉｎｇ，ＣｈｉｎａＩｎｓｔｉ...     

重庆大学危岩锚固工程简介

重庆大学18层高层建筑物拟建在嘉陵江高陡斜坡脚下,斜坡上部陡崖为侏罗系上沙溪庙组巨厚层砂岩,岩石原生及岸剪裂隙发育,危岩直接威胁着建筑物。川地208队采用锚杆加固及涂抹砂浆水泥护坡综合防治工程,效果明显。     

鞍山某基坑支护工程事故分析

论述了鞍山某基坑支护工程设计参数的选取与加固措施,分析了出现事故及险情的原因,总结了鞍山地区基坑支护设计与施工的经验和教训。     

Earth System Science: Conception and Misconception——To the Third Conference on Earth System Science,Shanghai

Earth system science should not be understood as an all embracing term that combines various disciplines studying the planet Earth. Rather, it is a new approach to consider interaction between its various subsystems, and seeks to integrate various research fields to understand the Earth as a system. Earth system science has developed from global changes studies, then extended into the deep geological past and now is facing a new challenge connecting the surface processes with those in the Earth’s interior.     

准中4区块侏罗系头屯河组滩坝及风暴沉积特征

在准噶尔盆地中部(简称准中)4区块侏罗系岩心观察的基础上,考虑粒度分析、薄片镜下观察及古气候恢复成果,认为该区头屯河组沉积时期发育滨浅湖滩坝沉积;以典型风暴沉积构造的识别为基础,提出一种与滩坝相伴生出现的新的风暴岩类型——滨浅湖风暴岩,并建立理想垂向序列模型,自下至上依次为:递变、块状层段(Sa),平行层段、冲洗交错层段(Sb),波状层段(Sc);断续纹层段(Sd)和滨浅湖泥岩段(Se).该类风暴岩发育在正常浪基面之上的滨浅湖地区,与半深湖风暴岩相比,更易遭受后期波浪改造而难以完整保存;因其发育的平面位置不同,滨浅湖风暴岩序列顶底的沉积物可以是氧化色调的滨浅湖泥坪沉积物或是正常的滨浅湖滩坝沉积物.滨浅湖风暴岩的提出完善了滨浅湖滩坝沉积体系,为研究区古地理、古气候特征的恢复提供线索,为滩坝的成因和沉积环境研究提供思路,对准噶尔盆地隐蔽油气藏的勘探具有一定指导意义.     

锚拉杆张拉力和摩阻力的现场实验研究与分析

对锚拉桥台锚拉杆进行了２０小时的现场试验,获得了大量实验数据,对张拉后锚拉杆的张拉力与长度、时间、温度和焊接接头的关系以及土对锚拉杆的摩阻力变化及分布规律作了分析与研究。研究结果对指导该类构筑物的设计与施工有着重要的理论与工程实用价值。     

锈蚀钢筋在疲劳荷载作用下压磁场分布研究

针对锈蚀钢筋的疲劳损伤与寿命评估中的难度大、精度低等问题,引入压磁检测技术,对锈蚀钢筋疲劳过程中的压磁场分布进行检测,从宏观与微观相结合的角度分析压磁场分布与疲劳损伤之间的联系。试验结果表明,锈蚀钢筋的压磁场分布能够反映疲劳损伤的演变规律,疲劳后期非线性特征加剧,锈蚀率及应力幅越大则变化越为明显,磁感强度值、磁场分布梯度、"反转"现象等均有助于进行疲劳损伤评价与寿命预测。研究结果可为压磁无损检测技术在钢筋混凝土结构中的应用提供依据。     

粉喷桩技术加固软土地基

简介了水泥粉体喷射搅拌加固软土地基的工作机理,结合沪蓉高速公路(沪宁段)地基处理实践,论述了粉喷桩加固软土地基的计算方法.采用粉喷桩加固软基,可加快路堤填土速率,铺筑路面后的工后沉降量能得到有效地控制,保证了工程质量.