2009年新疆新发现矿产地21处

2009年自治区地矿局全年新发现矿产地21处,提交可供开发矿产地10处以上。在煤炭资源勘查方面,东疆地区煤炭资源预查探求1000米以浅的煤炭资源1927亿吨,新增1117亿吨。库木塔格—沙尔湖、大南湖—野马泉和淖毛湖3个煤田探求资源量1509亿吨,新增745亿吨,     

高职学生自我概念发展存在的主要问题及辅导对策

本文从探析高职学生自我概念发展存在的主要问题着手,探求有效的辅导策略.     

掺钢铁渣粉混凝土收缩特性及体积安定性探讨

钢铁渣粉是一种新型的固体废弃物综合利用的产品,作混凝土掺合料有利于改善混凝土的工作性,其配制的混凝土后期强度高。试验主要研究了掺钢铁渣粉混凝土的干缩以及通过高温养护研究其体积安定性,并与纯水泥混凝土、掺矿渣粉混凝土和双掺矿渣粉、粉煤灰混凝土作对比,试验结果表明,掺钢铁渣粉的混凝土干缩值低于掺其他掺合料混凝土的干缩值,并且对混凝土安定性没有影响。     

高职贫困生心理现状与资助体系研究

从高校贫困生的心理现状及成因分析八手,通过分析当前高职贫困资助系,探求解决高职贫困生资助对策.     

粉煤灰混凝土的试验研究

文章对掺粉煤灰混凝土的系列配合比进行设计,经对粉煤灰掺量分别为20%、25%、30%的系列粉煤灰混凝土配合比进行试验,其中掺量为25%的粉煤灰混凝土其工作性能效果最佳。粉煤灰混凝土的优点是混凝土的工作性能好,混凝土坍落度损失小,适用于商品混凝土及远距离运输,提高工程质量,节约水泥,降低混凝土成本,节约资源等。     

利用浅钻进行生产勘探—探求高级储量的可行性分析

针对南芬铁矿采场台阶逐年变窄的趋势，采用单一的槽探形式进行生产勘探探求高级储量，控制矿体巳很难适应矿山生产的需要，而运用浅钻辅之以槽琛的形式进行生产勘探探求高级别地质储量，将会弥补这一不足，收到很好的效果。     

石英砂的品质对冰铜生产的影响

分析了闪速冶炼中石英砂品质对冰铜生产的影响,以探求取得更好经济效益的途径。     

钢纤维和聚丙烯粗纤维对活性粉末混凝土强度和延性的影响

众所周知,混凝土强度越高,脆性越显著,特别是超高强度混凝土.本文就钢纤维和聚丙烯粗纤维对掺偏高岭土活性粉末混凝土抗压强度和延性的影响进行了研究,结果表明:掺入一定量的钢纤维,可以改善混凝土内部孔隙结构,延迟和阻碍裂缝的形成和发展,从而提高混凝土的抗压强度,改善混凝土的脆性;掺入一定量的聚丙烯粗纤维,混凝土强度不会提高,但具有改善混凝土脆性的作用.     

新型复合材料钢纤维混凝土的性能与应用

本文结合钢纤维混凝土的性能机理,对钢纤维混凝土多项性能进行分析,并根据钢纤维混凝土独特的性能,展望钢纤维混凝土应用前景。     

模拟冻结法施工环境对大体积混凝土的性能影响

模拟大体积混凝土在冻结法施工环境的状态,将混凝土浇筑7 h后施加?5/60 ℃和?5/70 ℃温差,测试施加模拟环境后混凝土的超声波参数、抗压强度、劈裂抗拉强度、氯离子扩散系数和冲击倾向性,分析混凝土的扫描电镜微观形貌。结果表明,冻结施工环境对于混凝土内部会造成一定的损伤,且平行于加温方向的损伤要大于垂直方向,C50混凝土的损伤大于C70混凝土,温度梯度会加剧混凝土内部的损伤。模拟冻结环境会对混凝土抗压强度、劈裂抗拉强度、氯离子渗透性能和冲击倾向性造成不利影响,温差与性能降低率正相关,且这种影响对于低强度混凝土更加显著。模拟冻结环境造成混凝土试块的内部微观结构不均匀,低温端混凝土结构比较疏松,高温端结构比较致密,导致部分混凝土性能的降低。      

Field Study of Concrete Maturity Methodology in Cold Weather

The objective of this study was to assess the reliability and potential benefits of using the concrete maturity method in cold weather. This paper reviews the concrete maturity method, describes the technology and field observations, and discusses potential benefits of using concrete maturity in cold climates. The concrete maturity method is based on the idea that concrete strength development is strongly correlated with the curing temperature history. Modern sensor and processing devices (loggers) are able to measure and record the temperature of concrete over time. This information could be used to predict concrete strength over time. Findings from a case study in application of the maturity method in an industrial construction project in Edmonton, Alta., Canada indicated a significant potential time and cost reduction. The study also indicated that the concrete maturity methodology enables reliable quality control through the accurate estimation of in-place concrete strength. The real time information available through the concrete maturity method allowed the project manager to be proactive in managing heating and protection to ensure that the proper level of concrete strength was developed.     

韶钢炉卷主轧机设备基础大体积混凝土温度和裂缝的控制实践

以韶钢炉卷主轧机设备基础大体积混凝土施工为例，从大体积混凝土配合比的确定、温度应力分析、混凝土保温材料厚度计算、混凝土的泵送和浇筑、后期养护以及大体积混凝土内部温度的监测等方面进行了理论应用研究，为同类型设备基础的施工提供切实可行的实践经验。     

Stiffness Degradation and Time to Cracking of Cover Concrete in Reinforced Concrete Structures Subject to Corrosion

Corrosion-induced cracks in reinforced concrete (RC) structures degrade the stiffness of the cover concrete. The stiffness degradation is mainly caused by the softening in the stress-strain relation in the cracked concrete. Limited efforts have been made to model the cracking and the corresponding effects on the cover concrete, despite of its importance in assessing and modeling the behavior of RC structures. This paper proposes a stiffness degradation factor to model the stiffness degradation of the cover concrete subject to cracking. The proposed factor is computed in terms of the cracking strain corresponding to the maximum opening of the concrete cracks based on an energy principle applied to a fractured RC structure. The time to cracking of the cover concrete is then determined as the time from the corrosion initiation needed by the crack front to reach the outer surface of the cover concrete. The proposed stiffness degradation factor and the method to compute the time to cracking are illustrated through two numerical examples. The times to cracking of the cover concrete that are predicted using the proposed method are in agreement with the measured values from laboratory experiments.     

Roca Spur Bridge: The Implementation of an Innovative Deicing Technology

The heated deck of Roca Spur Bridge is the first implementation in the world using conductive concrete for deicing. Conductive concrete is a concrete mix containing a certain amount of electrically conductive components in a regular concrete matrix, designed to enable conduction of electricity. Due to its electrical resistance, conductive concrete can generate enough heat to prevent ice formation on a paved surface when connected to a power source.     

混凝土极限强度与硬度的关系试论回弹法测试混凝土强度

形成混凝土结构的最终目的是能承受规定荷载和使用环境下的耐久性。混凝土极限荷载的大小受三种破坏模式的制约。回弹法检测混凝土强度是无损检测,又简便快捷,而颇受青睐,但回弹法仅仅是广阔混凝土结构平面上的一个点,是通过其本身硬度的反作用力（回弹值）来间接换算混凝土的强度。     

Transverse Thermal Expansion of FRP Bars Embedded in Concrete

Fiber reinforced polymers (FRPs) have a thermal expansion in the transverse direction much higher than in the longitudinal direction and also higher than the thermal expansion of hardened concrete. The difference between the transverse coefficient of thermal expansion of FRP bars and concrete may cause splitting cracks within the concrete under temperature increase and, ultimately, failure of the concrete cover if the confining action of concrete is insufficient. This paper presents the results of an experimental investigation to analyze the effect of the ratio of concrete cover thickness to FRP bar diameter (c/db) on the strain distributions in concrete and FRP bars, using concrete cylindrical specimens reinforced with a glass FRP bar and subjected to thermal loading from ?30?to?+80°C. The experimental results show that the transverse coefficient of thermal expansion of the glass FRP bars tested in this study is found to be equal to 33 (×10?6?mm/mm/°C), on average and the ratio between the transverse and longitudinal coefficients of thermal expansion of these FRP bars is equal to 4. Also, the cracks induced by high temperature start to develop on the surface of concrete cylinders at a temperature varying between +50 and +60°C for specimens having a ratio of concrete cover thickness to bar diameter c/db less than or equal to 1.5. A ratio of concrete cover thickness to glass fiber reinforced polymers (GFRP) bar diameter c/db greater than or equal to 2.0 is sufficient to avoid cracking of concrete under high temperature up to +80°C. The analytical model, presented in this paper, is in good agreement with the experimental results, particularly for negative temperature variations.     

混凝土裂缝成因与控制

判断和分析混凝土裂缝的成因是有效地控制和减少混凝土裂缝产生的最有效的途径。混凝土的裂缝是一个综合性的问题，主要是由结构构件的设计、材料的选用、混凝土的配合比、施工环境以及外界因素等多方面原因造成的。混凝土裂缝的控制应从这几个方面进行综合考虑。     

Differences in tachistoscopic recognition between abstract and concrete words as a function of visual half-field and frequency

This experiment demonstrated that the greater right visual half-field (VHF) superiority for abstract words than for concrete words reported in two previous studies generalized to an independent, larger sample of abstract and concrete nouns. In addition, degree of concreteness was found to be positively related to overall recognition, with high concrete words averaging 38% correct, moderate concrete words averaging 30% correct, and abstract words averaging 20% correct. Analyses of ratio scores indicated that high frequency abstract words showed a significantly larger right VHF asymmetry than high frequency moderately concrete words or high frequency high concrete words. Groups of abstract, moderately concrete and high concrete words were also matched on right VHF recognition, to evaluate whether differences in VHF asymmetry were secondary to the differences in overall recognition. A significant interaction between VHF and word class was found, again indicating larger right VHF superiority for the abstract words. The data are consistent with previous suggestions that some left VHF concrete words are recongized by the right hemisphere.     

Experimental Study of Normal- and High-Strength Concrete Confined with Fiber-Reinforced Polymers

The experimental program reported here was conducted to gain insight into the behavior of concrete confined with fiber-reinforced polymers (FRPs). A total of 112 cylindrical concrete specimens, each 150 mm in diameter, 300 mm in height, and concrete strength up to 112 MPa, were tested under monotonic uniaxial compression. Test variables included amount of FRP, strength and stiffness of FRP, concrete strength, and the health of concrete at the time of strengthening. Results showed that, with an increase of the unconfined concrete strength, the strength enhancement, energy absorption capacity, ductility factor, and work (energy) index at rupture of FRP jackets all decreased remarkably. A positive correlation was found between concrete ductility and FRP rupture strain. A gradual post-peak failure of the specimens, observed previously from FRP-confined concrete columns tested at the University of Toronto, was also observed in some of the current tests. This ductile failure, attributed to the gradual unzipping failure of FRP jacket, is related to specimen size and is explained in terms of various confinement parameters.