Genealogy of hypoplasticity and barodesy

This article is an attempt at providing an insight into the development of hypoplasticity (including barodesy, which is a recent development of hypoplasticity) as a theory elaborated since 1977, when the first version was published by the first author, until present. The multiplicity of the many versions published since then is hard to overlook. This article presents a review and insight into the evolution of a theory and the struggle to formulate a satisfactory constitutive law. Among the many proposed versions, we focus on those ones that can be seen as changes of paradigm. Copyright © 2016 John Wiley & Sons, Ltd.     

Proportional stress and strain paths in barodesy

Asymptotic behaviour of soil deserves particular attention: If soil is deformed with a proportional strain path, the resulting stress path approaches asymptotically a proportional stress path. In this arcticle, we review existing experimental evidence on this phenomenon and discuss it in the frame of barodesy. Here, the presented relation is a modification of a barodetic expression and includes Jáky's relation, inhibits tensile stress and is able to predict asymptotic stress ratios based on experimental findings. The proposed relation is compared with experimental data as well as with the so‐called stress‐dilatancy relations and other constitutive relations proposed so far. Copyright © 2015 John Wiley & Sons, Ltd.     

An improved version of barodesy for clay

Barodesy is a constitutive model based on proportional paths and the asymptotic behaviour of soil. It was originally developed for sand in 2009 by Kolymbas, and a version for clay was introduced in 2012. A shortcoming of former barodetic models was that tensile stresses can occur for certain dilative deformations. In this article, an improved version of barodesy for clay and a simplified calibration procedure are proposed. Basic features are shown, and simulations of element tests are compared with experimental data of several clay types.     

Comparison of two small-strain concepts: ISA and intergranular strain applied to barodesy

Acta Geotechnica - The intergranular strain concept (IGS) and intergranular strain anisotropy formulation (ISA) are state of the art extensions to describe small-strain effects. The main...     

The critical state behaviour of barodesy compared with the Matsuoka–Nakai failure criterion

Barodesy is a new approach to constitutive modelling of soil. It is based on Goldscheider's principles and maps stretching directions onto corresponding stress directions with the help of a simple exponential function. This mapping also determines a critical state surface in principal stress space. The article investigates this surface and relates it to the well‐known Matsuoka–Nakai failure criterion. It turns out that the difference between these two surfaces is negligible for practical applications. Copyright © 2011 John Wiley & Sons, Ltd.     

Extension to barodesy to model void ratio and stress dependency of the K 0 value

Barodesy is a new framework for constitutive modelling of soils. The actual version uses a constant value of the coefficient of earth pressure at rest K ₀, which contradicts experimental findings. A straightforward modification is presented here to remove this shortcoming. The calibration of the material parameters remains as simple as in the original model.     

Second-order approximation to the variance of a proportion

The second-degree Taylor polynomial for a ratio is used to derive approximations to the means, variances, and covariances of proportions.     

二阶双系数动态亚格子应力模型

基于亥姆霍兹速度分解定理和Smagorinsky模型,提出二阶双系数动态亚格子尺度应力模型,即亚格子尺度应力是可解的应变率张量和旋转率张量的函数。应用有限差分法对此模型的控制方程进行了离散,并数值模拟得到了弯管内部的流场分布和压力分布。把雷诺数为40000的弯管流动的实验数据和此模型的模拟结果相比较,证明此模型是可行、可靠的。     

基于二阶评判法在地下水水质中的研究

利用FUZZY数学二阶综合评判模型,是指在评判空间:S=(X,U,R)上进行一阶综合评判,求出评价指数向量D1、D2、D3.再令U1=(D1、D2、D3),于是R1:X*U[0,1],然后在新的评价空间,S1=[X、U1、R1]上进行综合评判,求出二阶评判指数向量D=｛f1、f2…fm｝,并以指数的大小来决定X1、X2、X3…Xm的先后次序.     

改企建制中的财务工作

根据国务院和国家建设部有关事业性质的勘察设计单位要逐步改成企业的指示精神,各省市的建筑设计单位均在进行由事业单位改成企业单位的改制工作。尽管各地方在此项工作中的进展程度不尽一致,但大多数省市级设计院都普遍感到这项     

中国勘察设计协会2005年工作总结和2006年工作设想

现在我代表中国勘察设计协会秘书处，向大家报告2005年的工作，提出今年的工作重点设想，请大家提出意见和建议。     

无人机在地质工作中的应用

当前无人机作为一种新兴工具在诸多领域被广泛应用,由于其机动灵活、成像快速广泛的优点也逐渐成为地质工作者的新宠,在野外地质勘查及地质研究工作中逐渐被应用起来。本文在介绍利用无人机进行地质研究的基本原理及工作流程基础上,在现代沉积、古代构造特征分析、古代岩体切割关系研究等方面进行了一些尝试,完成了无人机地质数据采集、处理、地质分析的一整套流程工作。实践表明,无人机成像系统可获取地表或垂直崖壁的高分辨率、连续覆盖影像,尤其是对于地质工作者难以到达的危险区域可抵近观察成像。其采集的影像经过处理后,既能反映宏观整体,又能兼顾刻画地质细节。可见,无人机在地质勘查及地质研究中有着广泛的应用前景。     

MAPGIS在地质工作中的应用

在地质工作时需编制大量图件和附表,本文介绍MAPGIS软件将矢量化图件中储量估算面积参数数据等属性数据转到文本中,根据标准图件中点和线图元的位置将其所处位置的坐标值转成文本数据,可通过这些数据进行储量估算,编制各种表格和为报告文字编写提供数据资料,应用这些简便工作方法及技巧,可大大提高工作效率和质量。     

李希霍芬与中国之地质工作

文章原稿系用英文写成,曾载《中国地质学会会志》1933年第3期,以纪念李希霍芬百年诞辰。原文由李海晨汉译刊登于《方志月刊》1933年第6卷第12期,37～38页。今年为李希霍芬逝世100周年,本刊重新刊发李海晨翻译的文章,介绍李希霍芬对中国地质所做出的贡献以及他的科学精神,以激励有志的年轻学者。     

无人机在地质工作中的应用

当前无人机作为一种新兴工具在诸多领域被广泛应用,由于其机动灵活、成像快速广泛的优点也逐渐成为地质工作者的新宠,在野外地质勘查及地质研究工作中逐渐被应用起来。本文在介绍利用无人机进行地质研究的基本原理及工作流程基础上,在现代沉积、古代构造特征分析、古代岩体切割关系研究等方面进行了一些尝试,完成了无人机地质数据采集、处理、地质分析的一整套流程工作。实践表明,无人机成像系统可获取地表或垂直崖壁的高分辨率、连续覆盖影像,尤其是对于地质工作者难以到达的危险区域可抵近观察成像。其采集的影像经过处理后,既能反映宏观整体,又能兼顾刻画地质细节。可见,无人机在地质勘查及地质研究中有着广泛的应用前景。     

Domesticating home anchored work: Negotiating flexibility when bringing ICT based work home in rural communities

Based on a study of people conducting ICT based work from home in Scotland and Norway, the article analyses how work is negotiated and integrated with non-paid activities in the household and local community. The article fills a gap in that it focuses on rural contexts rather than the urban work life often depicted in literature on flexibility and work. When work is brought home, a domestication process takes place whereby practices of work are negotiated and integrated into everyday life, sometimes changing common perceptions of where and when work is “in” or “out of place”. While working from home is common in rural areas, the study shows that ICT based knowledge related work is still seen as relatively “out of place”. Drawing on the domestication concept, the study shows how community norms about accessibility, interaction and where to be at certain times, had to be renegotiated when this type of work was conducted from home. Imbued in these negotiations were subtly often tacitly communicated moral conceptions on what constitutes good parenthood (in particular motherhood) as well as “real” work. Both men and women reported benefits in terms of combining family and work obligations when working from home, but the tendency was still for traditional gender patterns to be reproduced. Women tended to fit work around the needs of the children, whereas men saw themselves first and foremost workers. Following the concept “doing gender” some challenged these patterns, but did so carefully in relation to the work organisation as well as the community. The impact of communities in regulating home anchored work suggests there may be a need for communities to take on a more active domestication process as more people conduct ICT based work with the home as the base, opening up the moral and normative geographies for when work is “in” or “out of place”.     

Stockholm city – university research in social work

Continuous contacts between academic research, local politicians and administrative experts have existed since the 1950s in the field of social work. Battles of mastery over knowledge have taken place. The original autonomy of academic research has been replaced by alliances between researchers and either techno-administrative experts or municipal politicians.     

Explosive gas pressure and work

Conclusion The inference is that work produced by an explosive tends to be a result of explosive generated gas pressure rather than the more constant shock energy.The breakage and adiabatic work respond to calculated borehole pressure relationships with a very high correlation. This indicates that the primary mechanism for rock breakage is explosive generated gas pressure.