高压输电结构系统的强度配合

论述了高压超高压输电线路机械和结构系统的强度配合原则和合理的强度配合秩序，阐述了我们目前在输电线路建设中存在的强度配合方面的问题及对策。

海砂在高强度CBGM中的应用

由于国外资源短缺,材料来源狭小,以质量为先本着就近取材的原则,有效利用当地材料既满足质量要求又可以节约成本。本项目附近海砂储量丰富,运输方便。海砂颗粒均匀集中,与机制砂掺配合理使用可以提高CBGM强度。

关于混合砂浆配合比强度的研究

本文利用建工系建材试验室（二级实验室），对校外建筑工程所做的、一定强度等级的混合砂浆配合比试验强度的成果，运用概率理论及数理统计的方法，研究混合砂浆配合比强度，由７天强度平均值增加到２８天强度平均值的增长规律。为建筑工程施工提供科学依据。

基于ANSYS的动车车轮强度分析

依据TB/T 1718-2003标准中轮轴过盈量的规定,对CRH380BL动车组新车轮与磨耗车轮进行了过盈配合强度评价;在考虑轮轴过盈量下,依据UIC 510-5-2003标准确定了新车轮与磨耗车轮的载荷工况及载荷大小,分别在直线工况、曲线工况及道岔工况下对其进行静强度评价。分析结果表明:按照相关标准,CRH380BL动车组车轮过盈配合强度及静强度均满足设计要求。

新型土体固化剂加固土的力学性能研究

新型土体固化剂由水泥、矿渣、钢渣、石膏和外加剂等为原材料生产而成,通过室内配合比强度试验和现场取浆强度试验研究新型土体固化剂加固土的无侧限抗压强度。以苏州市某在建地铁车站工程场地内典型土层为例,探讨了不同土质、新型土体固化剂掺量以及养护龄期对加固土强度的影响,对试验数据进行了线性分析,得到了加固土强度与新型土体固化剂掺量、养护龄期成正相关关系。为进一步验证新型土体固化剂加固土的实际效果,在工程现场进行搅拌桩试桩并对桩体浆液取样试验,通过分析表明现场取浆强度试验结果与室内配合比强度试验结果较为一致。相关结论可为新型土体固化剂的使用提供借鉴。

土工格栅混凝土的制备与配合比试验研究

为了提高植生型混凝土的抗拉强度,防止混凝土在护坡应用中产生拉伸断裂的现象,在植生型混凝土中间横向铺一层土工格栅,既能提供植被生长所需环境,又能满足使用强度。试验表明,土工格栅对混凝土的抗压强度影响不大,对抗折和劈裂抗拉强度最高提升20%。土工格栅的加入会使混凝土的孔隙率降低2%~4%。采用正交试验分析了水灰比、用水量和骨料级配3个配合比因素对土工格栅混凝土抗压强度、连通孔隙率和沉浆面积率的影响。结果表明:采用孔径为3.5 cm的塑料土工格栅,粗骨料选用级配为10~20 mm的碎石,用水量为60 kg/m3和水灰比为0.35进行配合比设计,土工格栅混凝土的工作性能最优。

谈水泥砼路面的砼配合比设计

本文简述了路面水泥砼配合比设计的依据 ,设计要求 ,设计参数及其计算方法 ,并概略的介绍了正交试验法。

棒形悬式复合绝缘子金属附件连接区机械性能的研究

介绍了国内外棒形悬式复合绝缘子金属附件连接区的设计结构,从不同厂家芯棒、压接力和生产工序三方面研究了连接区采用压接式结构对产品机械性能的影响,提出了在设计连接区时应考虑圆度、连接区的长度、端口的密封性、压块的长度及壁厚等因素。通过试验,认为压力小,易抽芯;压力大,易损伤芯棒。进行二段硫化后,强度降低了约20%,经原压力补压后,连接区强度可恢复,强度配合合理。推荐70kN级压力值可控制在(12.5～13.0)MPa,100kN级压力值可控制在(20.0～20.5)MPa以及160kN级压力值可控制在17.5MPa,压两次,保压时间均为6s。

水泥粉煤灰稳定碎石基层性能研究

该文针对少(林寺)—洛(阳)高速公路的实际情况,主要对水泥粉煤灰稳定碎石的强度特性和收缩特性进行研究,并进行了不同配合比强度和收缩试验,分析了不同因素对其性能的影响,对高等级公路路面基层的设计具有一定的参考价值。

葛双Ⅱ回覆冰断线倒塔事故的原因分析

葛双Ⅱ回覆冰断线倒塔事故的原因分析中南电力设计院姚茂生葛双Ⅱ回于１９９３年１１月因覆冰断线倒塔之后，对该５００ｋＶ线路事故提出修复原则并实施。１９９４年１１月又遭受几乎同样的断线倒塔气象。现在提出ＩＥＣ的规定，以深人探讨事故的原因及防范措施。１事故情...

Thermal-hydro-mechanical coupling stress intensity factor of brittle rock

A new calculation formula of THM coupling stress intensity factor was derived by the boundary collocation method, in which an additional constant stress function was successfully introduced for the cracked specimen with hydraulic pressure applied on its crack surface. Based on the newly derived formula, THM coupling fracture modes （including tensile, shear and mixed fracture mode） can be predicted by a new fracture criterion of stress intensity factor ratio, where the maximum axial load was measured by self-designed THM coupling fracture test. SEM analyses of THM coupling fractured surface indicate that the higher the temperature and hydraulic pressure are and the lower the confining pressure is, the more easily the intergranular （tension） fracture occurs. The transgranular （shear） fracture occurs in the opposite case while the mixed-mode fracture occurs in the middle case. The tested THM coupling fracture mechanisms are in good agreement with the predicted THM coupling fracture modes, which can verify correction of the newly-derived THM coupling stress intensity factor formula.

Effect of Recycled Coarse Aggregate on Concrete Compressive Strength

The effect of recycled coarse aggregate on concrete compressive strength was investigated based on the concrete skeleton theory. For this purpose, 30 mix proportions of concrete with target cube compressive strength ranging from 20 to 60 MPa were cast with normal coarse aggregate and recycled coarse aggregate from different strength parent concretes. Results of 28-d test show that the strength of different types of recycled aggregate affects the concrete strength obviously. The coarse aggregate added to mortar matrix plays a skeleton role and improves its compressive strength. The skeleton effect of coarse aggregate increases with the increasing strength of coarse aggregate, and normal coarse aggregate plays the highest, whereas the lowest concrete strength occurs when using the weak recycled coarse aggregate. There is a linear relationship between the concrete strength and the corresponding mortar matrix strength. Coarse aggregate skeleton formula is established, and values from experimental tests match the derived expressions.

Mixing ratio design of emulsified asphalt cold recycled mixture based on gyratory compaction molding

In order to study the application of gyratory compaction molding method in emulsified asphalt cold recycled mixture and optimize the relevant technical parameters, the study was carried out according to splitting strength, stability and water stability test;the design of the experiment involved changing gyration number, emulsified asphalt and water content, molded specimen temperature and other factors to analyze the volume parameters, mechanical properties and water stability. The results show that both the maximum dry density and dry and wet splitting strength ratio(DWSSR) of emulsified asphalt cold reclaimed mixture are improved by the rotary compacting method, while the porosity and the optimal dosage of water are reduced. Furthermore, with the increase of compaction times, the porosity and splitting strength index both change exponentially. DWSSR and porosity are consistent with quadratic functions. The use of gyratory compaction for 70 times at 25 °C and the optimum dosage of emulsified asphalt can be determined based on the splitting strength ratio. The high-temperature stability and water damage resistance of the pavement can be improved by the use of rotary compacting method effectively, and the early strength and road performance are higher than the regulatory requirements.

Medical Image Registration Based on Phase Congruency and Regional Mutual Information

In this paper, a new approach of muhi-modality image registration is represented with not only image intensity, but also features describing image structure. There are two novelties in the proposed method. Firstly, instead of standard mutual information （ MI ） based on joint intensity histogram, regional mutual information （ RMI ） is employed, which allows neighborhood information to be taken into account. Secondly, a new feature images obtained by means of phase congruency are invariants to brightness or contrast changes. By incorporating these features and intensity into RMI, we can combine the aspects of both structural and neighborhood information together, which offers a more robust and a high level of registration accuracy.

Workability Tests on Fresh Concrete Formulated with Eco-friendly Admixture

Extra-cellular compounds, secreted by microorganisms into their surroundings, can be integrated in concrete composition as admixtures. These substances are important in biofilm formation and some of them can be used as corrosion inhibitor of concrete reinforcement. This paper deals with products made with biological surface active compounds/agents allowing the development of more eco-friendly concrete. The influence of this environmentally friendly bio admixture on setting time, workability, bending and compressive strengths of various mortar based materials made of CEM I, CEM III and CEM V was studied. Mechanical tests were carried out to highlight the influence of admixture in workability and hardening of samples containing the biological product with ratio in the range of 0-2.5%. It was demonstrated that the presence of the new bio-compound admixture in mortar decreases their compressive strength after 28 days of standard curing, in spite of remaining higher than standard minimal strength. Furthermore, Vicat needle experiments have shown a tendency of this admixture to decrease the setting time. A discussion was finally proposed in order to correlate the setting times and the decrease of the mortar compressive strength, corresponding in fact to a hardening delay. This setting time delay could be linked to a delay of the admixtured mortar to increase its resistance. The slump results highlight the action of bio-admixture as a plasticizer on mortars because it increases their workability for a same water-cement ratio. This effect seems variable according to the added amount.

钢纤维混凝土在旧混凝土路面修补中的应用

介绍了钢纤维混凝土材料在旧混凝土路面修补中的应用特点，阐述了钢纤维混凝土材料的制作要求以及配合比设计方法，提出了施工中的注意事项，总结了钢纤维混凝土在路面中的应用优势。

谈六冲河特大桥主梁C60混凝土配制方法

结合工程实例,通过分析混凝土试配强度和单价,决定用机制砂配制C60混凝土,介绍了主梁高强混凝土的配制方法,试配结果显示其配制混凝土节约成本,抗压强度及各项物理力学性能指标均满足施工要求。

Utilization of Recycled Coarse Aggregate in Concrete Mixes

In this paper, the effect of the source of recycled coarse aggregate on the properties of concrete is investigated. The tests were conducted on concrete made from three sources of recycled aggregates： （1） old concrete with unknown strength, （2） old concrete with a known compressive strength of 21 MPa, and （3） old concrete with a known strength of 42 MPa. The three sources of recycled aggregates were used to produce new concrete with a target compressive strength of 21 MPa. The first and third sources of recycled aggregates were used in producing concrete with target strength of 42 MPa. A control mix was designed with aggregates from natural sources. The research included two methods of making recycled concrete. One concrete mix was produced using the recycled aggregate and adding more water than the control mix, to reach the target slump, while the second concrete mix was produced using the same amount of water as the control mix but with additional superplasticizer to maintain the target slump. The results obtained in this research showed that the concrete compressive strength depends on the source of recycled aggregates; the stronger the source of recycled aggregate, the higher the compressive strength of the produced concrete. Furthermore, the compressive strength of the first concrete mix was about 10%-20% lower than the compressive strength of the control mix. However, when superplasticizers were used, the compressive strength was around the same value as the control mix.

Identifying the functional groups effect on passivating perovskite solar cells

Many organic molecules with various functional groups have been used to passivate the perovskite surface for improving the efficiency and stability of perovskite solar cell(PSCs).However,the intrinsic attributes of the passivation effect based on different chemical bonds are rarely studied.Here,we comparatively investigate the passivation effect among 12 types of functional groups on para-tertbutylbenzene for PSCs and find that the open circuit voltage(VOC) tends to increase with the chemical bonding strength between perovskite and these passivation additive molecules.Particularly,the paratert-butylbenzoic acid(tB-COOH),with the extra intermolecular hydrogen bonding,can stabilize the surface passivation of perovskite films exceptionally well through formation of a crystalline interlayer with water-insoluble property and high melting point.As a result,the tB-COOH device achieves a champion power conversion efficiency(PCE) of 21.46%.More importantly,such devices,which were stored in ambient air with a relative humidity of ~45%,can retain 88% of their initial performance after a testing period of more than 1 year(10,080 h).This work provides a case study to understand chemical bonding effects on passivation of perovskite.