Frost-heave properties of saturated compacted silty clay under one-side freezing condition

In seasonally frozen regions, the frost-heave properties of soil play a significant role in its upper-structure performance and durability. To investigate the frost-heave behaviors of saturated, compacted silty clay soil widely used as subgrade material, a series of one-side freezing tests was carried out; and the freezing depth and frozen front effected by the compactness, temperature, overburden pressure, and water-supply condition were analyzed and discussed. The results show that the moving speed of the frozen front and growth rate of the frozen depth are positively correlated. The frost heave is maximum in the frost-heave stability condition. The frost ratio of saturated soil is proportional to the water supply and cooling temperature under a one-side freezing condition. The frost ratio of saturated soil is inversely proportional to the initial compactness of the soil specimen and the overburden pressure.     

黑河地区绿洲一沙漠环流的数值模拟研究

地气相互作用现象的研究对预测未来气候变化意义重大。黑河地区绿洲和沙漠戈壁地表间水热特性的强烈差异所引发的绿洲—沙漠中尺度环流 ,能够影响该区绿洲生态系统的维持和发展。利用中尺度数值模式RAMS成功地再现了黑河地区绿洲—沙漠环流 ,同时对环流出现时温、湿场的模拟分析表明 ,绿洲—沙漠环流的发生和发展直接依赖于非均匀下垫面热力场的差异 ,白天发展强盛 ,夜间作用小。环流作用能够保证绿洲—沙漠系统的物质和能量平衡 ,对沙漠戈壁环境中绿洲的维持十分重要     

SCOUR AROUND GROINS

l INTRODUCTIONGroins are smictures consmicted transverse to the river flow and extended from the bank into the river.They serve one or more of the following functions: 1) training of the stream flow, 2) protection of s treambank frOm erosion, and 3) imProvement of flow dePth for navigation. Groins, according to method andtyPe of construction material, are usually classified as permeable or imPermeable. However in this paPeranother wne is introduced, i.e. semipermeable groin, which is th…     

Selection of Multifractal Scaling Breaks andSeparation of Geochemical andGeophysical Anomaly

1Multifractalities have been observed and estimated formany quantities in physics, chemistry, as well as earth andspace sciences (see a review in Agterberg, 20011 Cheng,1999al Agterberg et al., 1993 1 Schertzer and Love joy, 1991).The multifractal theory has provided a superior distributiontype for describing the complex measures in comparison withthe ordinary statistical distributions. The former usually involves the multiple moments and parameters (Cheng, 1999alAgterberg et al., 1993 1 Sc…     

一个三维空区的震例研究

一个三维空区的震例研究朱元清１）夏从俊１）左力格图２）李慧民１）１）中国上海２０００６２上海市地震局２）中国武汉４３００７１国家地震局地震研究所主题词震源深度地震预报三维孕震空区华东地区自６０年代中期开始，国内外对强震前出现地震活动空区的研究日益增...     

答G.Stavrakakis和J.Drakopoulos的“VAN方法:自1981年以来矛盾和误导的结果”

把Stavrakakis和Drakopoulos(1996)(此后称作SD)中关于VAN表述与VAN真实内容作一简单比较,即可证明对方的批评是错误的。典型例子有: (1) 与Drakopoulos(1993)选择并加以讨论的一样,SD所讨论的VAN预报也是VAN预报中的一小部分。Varotsos等(1993b)当时已给予详细回答,并指出Drakopoulos等(1993)的7个例子中有4个没有考虑VAN电报提出的两个可供选择的震中位置,令人吃惊的是没有考虑被强调为最可能的那一个。在该文中SD对VAN预报的真实含意再次做了较大的改动。 (2) SD仅选择了那些VAN预报法具有较大偏差的情形来进行讨论。 (3) SD通过选择地区内的某些预报后在该地区出现的地震活动性而提出怀疑。本文将证明这些预报指的是远离有早期地震活动的另外地区。SD把VAN预报的两个例子说成是对应的余震,我们将证明这种观点是错误的。 (4) SD改变了VAN公布的单个SES和SES电活动性的超前时间。 (5) SD增加(或删除)对VAN观点及预报的批评措词,因此说明对方真正意思是急剧变化的。 (6) 虽然识别SES的标准已经由VAN发表,可SD仍称这种标准依据尚未形成。 (7) SD的示图是错误的,因为他们忽略了M_s=5.0地震(大地震)标准仅发生在预测地区,但也包括远处M_s=4.0～4.2的地震。 (8) SD称“没有一个主震被预报”,但VAN成功地预报了1987年至1989年间的3个处于调查中的最大主震,震中偏差小于50 km。 (9) SD认为如果已经发生了M_s≈4.0的“前震”,再成功地预报M_s=5.0的地震是毫无意义的(不管偏差Δr、ΔM达到多小)。这种观点是不对的。 (10) 虽然VAN已经阐明了只有M_s的预计值大于(或等于)5.0时才提出预报,可SD曲解了实验误差ΔM=±0.7的含意,并要求M_s≥4.3的地震都应被预报出来。这一要求是不对的。此外,我们将进一步证明SD关于“偶然预报成功的概率”计算是错误的,因为它违反了基本原理。     

GIS APPLICATION IN RESEARCH OF WILDLIFE HABITAT CHANGE——A case study of the Giant Panda in Wolong Nature Reserve

Ｉ.ＩｎｔｒｏｄｕｃｔｉｏｎＴｈｅＧｉａｎｔＰａｎｄａ(Ａｉｌｕｒｏｐｏｄａｍｅｌａｎｏｌｅｕｅａ)ｉｓａｎｅｎｄａｎｇｅｒｅｄａｎｉｍａｌｓｐｅｃｉｅｓｉｎｔｈｅｗｏｒｌｄ.Ｔｈｅｒｅａｒｅａｂｏｕｔ1000ｉｎｄｉｖｉｄｕａｌｓｌｅｆｔａｎｄｃｏｎｆｉｎｅｄｉｎｔｈｅｉｓｏｌａｔｅｄｍｏｕｎｔａｉｎａｒｅａｓｉｎｔｈｅｓｏｕｔｈｗｅｓｔｅｒｎｐａｒｔｏｆＣｈｉｎａ.Ｉｔｓｒｅｍａｉｎｉｎｇｈａｂｉｔａｔｃｏｖｅｒｓａｂｏｕｔ29,500ｋｍ2[2,6,11].Ｈｕｍａｎｅｎｃｒｏａｃｈｍｅｎｔｉｓｃｏｎｓｉｄｅｒｅ…     

FOOD CONSUMPTION AND NUTRITION IN RURAL AREAS OF MADHYA PRADESH, INDIA (WITH SPECIAL REFERENCE TO SAGAR DIVISION)

Ｉ.ＴｈｅＳｔｕｄｙＡｒｅａ:ＳａｇａｒＤｉｖｉｓｉｏｎＳａｇａｒｄｉｖｉｓｉｏｎｌｉｅｓｉｎｔｈｅｎｏｒｔｈｃｅｎｔｒａｌｐａｒｔｏｆＭａｄｈｙａＰｒａｄｅｓｈｂｅｔｗｅｅｎ23°10′ａｎｄ26°35′Ｎｌａｔｉｔｕｄｅｓａｎｄ78°04ａｎｄ80°38′Ｅｌｏｎｇｉｔｕｄｅｓ.Ｔｈｅｇｅｏｇｒａｐｈｉｃａｌａｒｅｓｉｓ38223ｋｍ2ｗｈｉｃｈｉｓｓｂｏｕｔ8.65ｐｅｒｃｅｎｔｏｆｔｈｅＳｔａｔｅ.ＴｈｅＳａｇａｒａｄｍｉｎｉｓｔｒａｔｉｖｅｄｉｖｉｓｉｏｎｃｏｎｓｉｓｔｓｏｆｆｉｖｅｄｉｓｔｒｉｃｔｓｖｉｚ.Ｓａｇ…     

阿尔丹地盾的磷酸盐风化壳

本文对阿尔丹地盾广泛发育的元古宙及中生代的含磷的风化产物多年研究的基础上,提出磷酸岩沉积物的结构、成分、地球化学特征。说明磷灰岩风化产物是类型磷灰石—碳酸盐基底上形成的。提出在中央-阿尔丹地块发现了风化壳磷酸盐矿的有利地质条件,由于在磷酸盐产物中含有高含量的 P_(?)O_5柠檬溶液,所以提出可能利用其作为再加工生产磷钙石(磷肥)粉的设想。