Archaeological Study on Reinforced Soil for Hydraulic Engineering in Ancient China

杨柳烟含灞岸春,年年攀折为行人。
好风若借低枝便,莫遣青丝扫路尘。

李老师把文章的资料发给我的时候,我没想到翻译将花这么长的时间,这可能是迄今为止我译过最难的一篇。我从学生时代断断续续就做过各种各样的翻译,各种专业,各种内容,甚至做过一次会议的现场同声传译(这是我非常高兴能够有机会尝试的一次体验,坐在隔音的小隔间,戴着耳机,切换着麦克风的频道,非常特别的一次体验),但这篇翻译是我翻译耗时最长的一篇。

这是一篇很有意思的文章,第一次听到是在一次土工合成材料会上,李老师做了一个报告,当时在座的Fumio Tatsuoka (龍岡 文夫) 教授也非常感兴趣。
李老师的报告总是有一种不一样的风格,每次都能够把知识讲得非常有趣,又容易理解。这篇文章的切入点是良渚古城的考古、息壤以及土工合成材料加筋。
等到文章译好,然后发现这篇文章该往哪投呢,它不像一个普通的论文,理论模型,数值模拟等等,倒是很像李老师《岩坛漫话》的风格。

论文的翻译是困难的,试举几个例子:

Continue reading “Archaeological Study on Reinforced Soil for Hydraulic Engineering in Ancient China”

Join us

It is the first time that I put on a post to say “Hey! Join us, if you are interested in.”

We are doing amazing research here with incredible enthusiasm and broad interests.

There are tons of reasons that people choose to do research; it could be a hobby, or to make a living, or any reason you name it, but my favourite reason is always that you love it. If you love your job, then you will do it with passion and happiness. 996 is never a problem only if you love it. (Well, it doesn’t mean 996 in our team…I never advocate that. See the photo, people played badminton; and we should do it more later on.)

My interests include (but not limited to)

1. Impact of electricity on clay minerals

By applying electric voltage on clay minerals, we look at the variation of its mineral structure and engineering behaviours. This could be a scientific research on clay mineral level (chemical & micro level); it could also be linked to potential engineering application in the area of geotechnical and geoenvironmental engineering.

2. Soil remediation and ground water treatment

This is a research area on removal of pollutants from contaminated soil or protection of ground water. This research topic can be linked to EK technique as well. And another possibility is to use Fe-rich clay minerals as redox materials for ground water treatment.

3. Dewatering and consolidation

This topic is about removal of water from very fine-grained soil, like sludge, slurry, clay, etc. These kinds of materials have very low hydraulic conductivity, but electro-osmosis can be an effective method for dewatering and consolidation of them. We are looking at the challenges of this EO technique in large scale of application.

4. Geosynthetics

We are interested in application of geosynthetics.

1) Reinforcement, which is a very popular application for decades and lots of people from academy and industry are doing it.

2) Filtration and drainage. This topic is related to dewatering and consolidation. One of the special issues that we are especially interested in is the clogging problem of geotextiles. There are lot of things to do, include mechanism of clogging, update of manufacturing and design code, invention of novel types of geotextiles.

3) One more thing about geosynthetics, which is special for our research is EKG. This novel material presents a new category of geosynthetic and I’ve been staying in this topic for over decade.

5. Unsaturated soil, constitutive model and numerical modelling

We are carrying out this research partially also because of EK technique. When applying EK technique, it is related to unsaturated soil and suction. Therefore, we’ve been developing completely new constitutive model and trying to apply it in suction measurement, EK design and also trying to develop code for numerical modelling and software for EK design.

6. Mining, tailing, liquefaction, etc.

More researches that are related to my basic interests previously mentioned are being explored, we will see more ideas and fantastic work coming up.

So…welcome to join us…

And also, any collaboration is welcome.

Looking forward to hearing from you

Yan-feng Zhuang (zhuang@tsinghua.edu.cn)

唧唧复唧唧,我是泰沙基

该贴部分引自知乎(英文部分另有出处,分别见下文链接)
Terzaghi文稿 | 土力学—工程科学的新篇章

“Soil Mechanics arrived at the borderline between science and art. I use the term “art” to indicate mental processes leading to satisfactory results without the assistance of step-for-step logical reasoning…To acquire competence in the field of earthwork engineering one must live with the soil. One must love it and observe its performance not only in the laboratory but also in the field, to become familiar with those of its manifold properties that are not disclosed by boring records…”

Karl-Terzaghi-The-Engineer-as-Artist

↓↓↓

Continue reading “唧唧复唧唧,我是泰沙基”

An interesting historical paper on electro-osmosis

I believe that most information is somewhere on the internet; the question is if you can find it. This is part of a paper about the history of electro-osmosis, which was digitized by google.
In ancient time, scientific discovery was communicated within scientists via correspondence, which is good, but rather impossible now. The latest news about coronavirus… Are those … working for helping people or just for publishing papers?

Porrett

汪闻韶与电渗

在对土中电渗问题的研究中,他澄清了电渗对饱和土力学性状的影响;提出了电渗和水力渗透混合流公式;解释了电渗加固软土的机理,说明了电渗在土力学中的应用:

1)是利用电渗对孔隙水动力学性的影响,在适当的布置下,使土体稳定性暂时获得加强。2)是利用电渗排水,降低土中含水量。3)是利用电渗促进土中束缚水移动的作用,促进地基软粘土层的固结。4)是利用直流电在土中所引起的离子交换和新化合物形成与胶积等物理化学作用,增进土的强度,减少土的塑性、干缩性。5)是利用电渗作用在土中灌注化学溶液以改进土的工程性质。六是利用连续间歇的电场作用,减少土壤侧面的阻力,可用于打桩、拔桩等工程。

汪闻韶的《直流电在土中作用及其对土的物理力学性的影响》论文获得中国科学院科学奖金三等奖。

汪闻韶_献身水利__情深似海_彭小东

Continue reading “汪闻韶与电渗”

电渗与疏浚淤泥脱水

Yan-feng Zhuang. Electro-Osmosis and Dredged Sludge Dewatering.
Ground Improvement. 2015, Vol.26 No.4, PP: 48-52.

摘要:本文以欧洲疏浚淤泥处理项目AMORAS 为对照,对比了电渗法和压滤法淤泥脱水的效果:电渗法 脱水可将淤泥含水量降低到40%,优于淤泥脱水54-67%的含水量要求(此处含水量根据岩土工程的定义计算);电渗法的脱水速度快,可减少储泥池的库容。EKG 材料的出现解决了电极腐蚀和电渗能耗过大的 问题,目前电渗法在大面积应用中的主要问题是电源功率过大,该问题通过重新设计直流电源,采用轮询通电的方法解决,目前已有专用的电渗电源,电渗法已有望进入真正工程应用阶段。
关键词:电渗;疏浚;淤泥脱水;EKG;轮询通电;AMORAS

庄艳峰-电渗与疏浚淤泥脱水

Development Of A New Redox-Active Porous Material For Groundwater Remediation

Yan-Feng Zhuang, Maggie L. White, Claire I. Fialips

Abstract
Laboratory experiments have shown that reducing iron in smectites promotes the degradation of various redox sensitive organics, including nitroaromatics and chlorinated compounds. Fe-bearing smectites have however never been used in the design of permeable reactive barriers (PRBs) for groundwater remediation. One basic requirement when designing PRBs is to keep their permeability equal to or higher than that of the surrounding aquifer materials to avoid affecting groundwater flow. Smectite clays are very low permeability materials and, when physically mixed with permeable materials, such as sand, clay particles can migrate and clog up pores, resulting in a progressive loss in permeability. In this study, we are developing a novel Fe-bearing clay-material suitable for permeable water treatment systems, including PRBs. Fe-smectite particles are tightly attached to the surface of sand grains using polyvinyl alcohol (PVA). To identify optimum procedures, we are studying the relationships between the size and texture of the sand grains, the clay/PVA and clay/sand ratio, the quality and extent of clay coverage, the stability of the clay-coated sand to changes in pH and redox conditions, and its hydraulic properties before and after iron reduction. The best clay coatings have been obtained using the most angular sands with rough surfaces and medium grain sizes (0.3-0.6mm). An optimum coating of 61.5 mg clay/g sand was obtained using the nontronite Nau- 2. The clay-coated sand is stable when pH is below 7 (no detachment of the clay particles). For pH higher than 7, a maximum of 14% of the clay-coating is detaching when the sample is not disturbed, and 28% if shaken. XRD analyses of the clay-coated sand also show that the coated smectite retains its swelling properties (d-spacing at 17.1Å after ethylene glycol treatment). The clay-coated sand is also stable to changes in redox conditions, with less than 15% detachment after 4h of treatment with sodium dithionite at 25°C. The coated clay is reducible, with a maximum reduction level of 83% (Fe(II)/Fe total). The hydraulic properties of the clay-coated sand are suitable for use in permeable systems. The effect of the reduced clay-coated sand on the degradation of redox-sensitive organics will be tested using nitrobenzene.

Development Of A New Redox-Active Porous Material For Groundwater Remediation

Upward gradient EKG and electro-osmosis for deep soft ground consolidation

Yan-feng Zhuang, Zhitao Liu, Zhengxin Li, Hongwei Wang, Tong Yang, Ganglin Li. Upward gradient EKG and electro-osmosis for deep soft ground consolidation. 11th International Conference on Geosynthetics, 16th-21st September, 2018, KGSS, Seoul, Korea. (Flash Disk, paper SS3-01)

ABSTRACT:
Electro-Kinetic Geosynthetics (EKG) presents a new category of geosynthetics. It inspires enthusiasm to apply electro-osmosis (EO) in large scale engineering applications, such as soft ground improvement, sludge dewatering, soil remediation, etc. This paper presents a kind of specially designed EKG and DC power source to carry out electro-osmotic consolidation for soft ground in vertical direction instead of horizontal direction. It is aiming at providing a better consolidation effect without degradation along depth for deep soft ground improvement. In-situ experiment shows that bearing capacity of the hydraulically filled sludge could be increased to 80-90 kPa after upward gradient electro-osmosis treatment and consolidation effect along depth is more homogenous than that of horizontal electro-osmosis using normal E-board. Development of EKG materials and automated DC power source are two key breakthroughs that pushing forward both researches and applications EO technique, which has over 200 years of history already.

Keywords: Electro-osmosis; EKG; consolidation; soft ground improvement

Upward gradient EKG and electro-osmosis for deep soft ground consolidation

Application of Novel EKG and Electro-osmosis in Hydraulically Filled Sludge Dewatering and Consolidation

Yan-feng Zhuang. Application of Novel EKG and Electro-osmosis in Hydraulically Filled Sludge Dewatering and Consolidation. Proceedings of 61h Asian Regional C onference on Geosynthetics, “Geosynthetics for Infrastructure Development”, 8th-llth Nov. 2016, in New Delhi. India. Central Board oflrrigation & Power
(CBIP), New Delhi. India: KN-55 ~ KN-63. (Keynote)

ABSTRACT

Electro-Kinetic Geosynthetics (EKG) inspires enthusiasms for research on electro-osmosis. Mechanically dewatering of hydraulically filled sludge is difficult due to low hydraulic permeability of sludge, while electro-osmosis provides a promising solution. Two types of EKG, E-board and E-tube, are developed for sludge dewatering. EKG solved the problem of electrode corrosion and new challenges is high electric power requirement. Energy level gradient theory is presented as a fundamental theory to propose design method for sludge dewatering. Key parameters of flow coefficient and time factor are discussed, including their test method, value range and scale effect. Roll polling electro-osmosis scheme is the solution for high power requirement. Estimation of power and design of roll polling electro-osmosis scheme is core of electro-osmotic dewatering design. Novel DC power source is custom built to realize the roll polling scheme. The DC power source of 80V/1000A has roll polling program embedded and it is in charge of 12 independent sections, which can deal with ~2000 square meters of hydraulically filled area.

Application of Novel EKG and Electro-osmosis in Hydraulically Filled Sludge Dewatering and Consolidation