一种斜向大断面拱座单桩基础隧道式CRD法开挖三维数值分析

某大桥拱座基础为斜向大断面单桩基础,具有大型基坑和隧道受力的特点,空间受力复杂,很有必要研究其力学行为。采用摩尔库伦屈服准则,考虑材料的弹塑性,通过MIDAS GTS软件建立三维整体模型,计算分析了CRD法开挖施工过程中围岩、初支、中隔壁、横撑应力、变形的情况,归纳出随着开挖步施进初支最大主拉、压应力的分布曲线和位移曲线图。结果表明该施工方案初支拉、压应力及变形均较小,开挖至距离基础底约8米处为变形和应力最大处,对施工方案的制定和施工监测有重要的参考作用。更多还原     

三里坪大坝两岸工程地质特征差异分析

三里坪水电站大坝为建造在复杂构造背景下的碾压混凝土双曲拱坝,大坝两岸工程地质特征差异明显,主要表现为大坝左右两岸断层和裂隙的组合形式有明显差异,设计及施工中需针对大坝两岸差异性工程地质缺陷采取不同的应对方案。简要介绍了三里坪水电站复杂构造背景下的大坝工程地质特征,并据此对左岸底滑面和右岸侧滑面作了地质模型概化。分析结果给坝肩抗滑稳定计算提供了理论依据。     

矿量分级制式观念有待创新

始自1909-1910年通行各国的多种矿量分级制式,在原则上是都以所谓地质信息的可靠性为标志。本文所倡议的矿量分级制式,将以总开发效益的可靠性为标志另行构筑,它能使矿块级别-吨位-品位指标的内在联系从幕后走到前台,使勘查者的各级矿量与开采者的三级矿量贯通一气。级差品位指标制在国内运行四十多年的成效,就是在块段吨位足够大的前提下尊重级别-品位依存关系的例证。     

浅谈地勘单位股份合作制改革中的问题和思路

文章介绍了西南有色地质勘查局三一○队基础工程公司股份合作制改革的情况,分析了基础工程公司股份合作制实践中存在的种种缺陷,提出了完善、深化改革的思路.     

Monetary policy shocks and exchange rates in Asian countries

In this paper, we empirically investigate the effects of monetary policy shocks on exchange rates in Asian countries. To do so, we use VAR models which impose sign restrictions on impulse responses to identify monetary policy shocks. We find that contractionary monetary policy shocks lead to significant exchange rate appreciation in Malaysia, the People’s Republic of China, and the Republic of Korea. However, in India, Indonesia, the Philippines and Thailand, we find either a significant depreciation or no significant effect. These results suggest that an interest rate increase (or decrease) may not necessarily shield Asian countries from exchange rate depreciation (or appreciation) pressure following a U.S. interest rate increase (or decrease).     

Attention Deficit/Hyperactivity Disorder in the Workplace Under the ADA in the Wake of Sutton and Its Companions

The terms Attention Deficit Disorder (ADD) or Attention Deficit/Hyperactivity Disorder (AD/HD) refer to a neurological impairment that affects the individual's ability to sustain attention and to behave in a calm, rational manner.³Although this disorder has long been considered to be restricted to childhood, recent research has demonstrated that many children carry it over into adult life and take it with them into the workplace. Most U.S. courts have treated AD/HD as a disability covered by the Americans with Disabilities Act (ADA).⁴However, in the summer of 1999, the U.S. Supreme Court made three decisions that will undoubtedly affect the future status of AD/HD and other impairments under the ADA. This article examines those decisions, how they affect the employment rights of AD/HD-afflicted employees, and the changes they will probably bring to litigation in this area. Because we have many reservations about the court's decisions, we not only voice our criticisms of the decisions, but also offer an alternative approach.     

严寒地区预防EPS板外保温薄抹灰裂缝的对策与建议

针对严寒地区EPS板外保温薄抹灰裂缝的实际情况,对材料、施工工艺、温度等因素分析,并提出预防裂缝的对策与建议。     

Nature-based recreation associated with connectedness to nature and leisure satisfaction among students in Brazil

ABSTRACT

There is growing evidence that nature-based recreation (NBR) during childhood promotes connectedness to nature, which in turn fuels NBR during adulthood. In addition to providing a number of health benefits, NBR participation may enhance leisure satisfaction, an important predictor of happiness and life satisfaction. In this exploratory study, we tested these hypothesised links using a path model with a cross-sectional sample of 224 Brazilian college students, where NBR participation during childhood increases connectedness to nature and NBR participation during adulthood, which in turn promotes leisure satisfaction. The model fit the data well χ² (2) = 1.924, χ²/df = 0.962 (N = 220, p = .38), CFI = 1.00, AGFI = .978, GFI = .996, and RMSEA = .00, with results showing an indirect positive link between NBR during childhood and leisure satisfaction, and a direct link between NBR during adulthood and leisure satisfaction. The indirect effect of connectedness to nature on leisure satisfaction was also significant: NBR during childhood fostered connectedness to nature, which motivated NBR during adulthood and higher levels of leisure satisfaction. Leisure practitioners can improve people’s leisure satisfaction by promoting engagement in NBR activities across life stages and emphasising connection to nature.     

中国休闲度假旅游的必由之路:从"黄金周"到带薪休假

“黄金周”长假期促进了假日经济的发展，开启了中国城镇居民休闲度假旅游的新时期，但“黄金周”“赶集式”的旅游也有不少负面影响。本文在分析“黄金周”旅游利弊的基础上，从自主式“个性化旅游方式的发展趋势、旅游的可持续发展、加快休闲制度与国际接轨等方面，论述了全面实行带薪休假制的必要性与可行性。     

长沙掺MgO拱坝变形监测资料分析

通过对外掺MgO混凝土的变形特性研究，建立起适合外掺MgO混凝土拱坝变形时效特性的数学模型，分析了长沙拱坝拱冠205.0 m，220.0 m，245.0 m高程径向位移的变化趋势和主要影响因素。分析结果表明拱冠径向位移主要受温度、上游水位以及时效的影响，且时效尚未稳定。