Defect and Pre-control Methods for Fair-faced Concrete Construction

At present, there is no definite quality standard for fair-faced concrete in civil engineering. Because the contractors are different in technique level and the fair-faced concrete construction is more complex than common concrete one and ease to cause defect. In this paper, the quality defect of fair-faced concrete is introduced and some pre-control methods from some aspects, including raw materials of concrete, casting, maintenance, steel bar cutting, formwork jointing treatment, defect mending, finished product protection and so on are presented.     

Interaction Working Behavior About the Internal and External Wall of Foam in place Cavity Wall

In order to study the stability of foam in place cavity wall, the capacity of reinforced concrete strip ear and tie involving in cavity wall deformation, the broken shapes and mechanical performance of the cavity wall, the effective measures was seaked to improve deformation capacity and overall performance of the cavity wall.13 patches of cavity wall and 1 patch of solid wall were built and seismic tests of which were carried out.The lnfluence of some constructional measures on mechanical behavior and deformation properties of the wall and vertical pressure and insulation layer thickness on the relative displacement difference of the internal and external wall of foam in place cavity wall was analyzed.Finally, the capability of reinforced concrete strip ear and tie working interactively between the internal and external wall of foam in place cavity wall was analyzed.It is found that deformation capacity of the cavity wall is improved efficiently with constructional column and the high bonding strength, shearing strength and pressure strength of foam in place insulating mortar have certainly a positive influence on the bearing capacity of the wall.The reinforced concrete strip ears play the leading role in reinforcing connection of the internal and external wall of foam in place cavity wall and guaranteeing out plane stability of the external wall.When walls crack seriously, the ties can play an important role in supporting and drawing the wall and preventing wall collapse.Furthermore, the reinforced concrete strip ears and ties which are the main construction measures to coordinate the internal and external wall work together perform a great variety of tasks.Therefore, the reinforced concrete strip ears and ties should be designed rationally to guarantee playing their respective roles.     

FEA About Capacity of Resisting Explosion Inside of Short Concrete Column With Steel Tube Confined

With the development of offense and defense strategy in future war and the application of high tech weapon, the demand is much improved to the resistibility level of defense engineering. LS-DYNA3D software is adopted to simulate the situation causing by the explosion of the commonly short concrete column and Short Concrete Column with Steel tube confined. The comparison includes chamber causing by explosion and nodes' displacement. The results show that steel tube-confined concrete structure can confine the displacement of core concrete, improve the structure's capacity of resisting explosion effectively, and enhance structure's elasticity and firmness.     

Inspection and Monitoring of Prestressed Anchoring System

Through concrete project examples, the technological methods and means for inspecting and monitoring the quality of the prestressed anchoring system in geotechnical engineering were expounded. The concrete inspection data have provided reliable evidence for evaluating qualities of geotechnical engineering.     

苜蓿生物技术研究进展

苜蓿是世界上重要的豆科牧草,它具有品质优良、易于栽培等特点,在生态环境保护方面也发挥着积极作用。随着分子生物学和植物基因工程的发展,在分子水平上对苜蓿进行遗传改良的研究已取得了部分成果。本文简单介绍了苜蓿组织培养的种类及影响因素,综述了近年来遗传转化和分子标记等生物技术在苜蓿研究领域的应用,并展望了苜蓿基因工程在今后研究工作中的重要地位和前景。     

Analysis and Treatment of the Quality Accident of Circle Beam in a Certain Big Wineshop

In this paper,through the analysis of the engineering quality accident of the top circle beam in a certain big wineshop,a mechanical model of the reinforced concrete circle beam is proposed.By calculation and analysis,the reason of cracking in the circle beam support was found out,and the correct calculated result was made out,so that the engineering quality accident was timety treated.     

Field test and deformation controlling for single tunneling lining stability

The construction process of anchor,fiber concrete and its mechanical principle of interaction with surrounding rocks is studied by field tests from the view of researching stability of single layer tunneling lining. The mechanical properties of single layer lining in the practical application of tunnel engineering are measured. On the basis of this study,the mechanism of single layer tunnel lining is discussed,which is finally applied to the engineering practice,formatting a set of theoretical support for the design method of single layer lining. Studies found that close effect between fiber reinforced concrete and rock is well,which shows that the single layer lining design method to ensure quality and safety proposed in this paper is feasible,and construction characteristic of retaining structure is reliable. The method can be widely applied in engineering practice,and has remarkable economic benefit and social benefit.     

Design method and homogeneity control of bridge fair-faced concrete

According to the structural characteristics of bridge engineering, the mix optimization design method of bridge fair-faced concrete was presented, and C30~C50 concrete with high cohesion and package, outstanding fluidity and excellent mechanical properties were prepared. Through the test of air content of fresh concrete, micro hardness and micro structure in different parts of hardened concrete specimens, effects of viscosity-modifying admixtures on homogeneity of concrete were discussed. The results showed that the composition of bridge fair-faced concrete were relatively homogeneous, and the microstructure were relatively dense. When C30 concrete mixed with 5 × 10 -5 cellulose ether or 6% silica fume (mass fraction of cementitious material), air content of fresh concrete were less than 2%, and slurry viscosity values were between 1 900 and 2 000 MPa·s. Also, the micro hardness values in different parts of hardened concrete specimens were closed. The results were applied in practical bridge engineering, which generally meets the apparent quality requirements of bridge fair faced concrete.     

食品工程原理理论课教学方法探讨

食品工程原理是食品科学与工程专业的一门重要专业基础课,是学好其他专业课程的基础。为了提高教学质量,结合该课程的特点,根据笔者的教学经验,在提高学生学习兴趣,培养工程思维能力,采用多样化教学方法与手段方面进行了探讨。     

Improvement of Alkaline Fillers on Anti-stripping Properties of Asphalt Concrete

Anti stripping is an important objective of asphalt concrete engineering.Effects of acidic and alkaline fillers on anti stripping of asphalt concrete, and the possibilities of solid powder wastes added into asphalt concrete as the filler, have been explored. The result shows that additions of alkaline filler such as limestone and EF material into asphalt concrete as the filler, compared to acidic fillers such as siliceous mineral filler and fly ash, can effectively enhance the Marshell stability, resilient modulus and split tensile strength for this mixture. Meanwhile, the anti-stripping ability of asphalt concrete would be greatly improved.     

Numerical Computing Method of Conductive Concrete Applied in Construction Heating Engineering

It is worthwhile for saving energy and protecting environment to use conductive concrete as an indoor heating engineering material. Indoor temperature is the key concern of heating system. Based on convection, radiation and Joule effect, a method to calculate temperature of concrete and indoor air was presented. The method did not need to model the air, which simplified the preprocessing. The numerical result agreed with experiment satisfactorily, with a difference of 2.40%, which proved the correctness of the model. Numerical tests of different conditions showed that electrical resistivity with higher potential than power voltage and concrete thickness was the key to increase heating efficiency.     

农作物秸杆改良土壤的方式与应用现状

农作物秸秆中含大量的碳、氮、磷、钾、钙、镁、硫和硅等多种营养元素,同时富含纤维素、半纤维素、木质素和蛋白质等有机物质,是一种可以资源化利用的固体废弃物资源。秸秆还田可以改良土壤,具体表现在秸秆还田是氮素的重要来源;秸秆还田可以提高土壤的保蓄性和缓冲性;秸秆还田能够改善土壤物理性质,改良土壤耕性;秸秆还田具有消除农药残毒和重金属污染的作用。此外秸秆还田还可以提高农作物品质、保护农村生态环境、促进农业的生态化发展。     

食品科学与工程专业实践教学改革探索

实践教学是本科教学的重要组成部分,是提高学生综合素质、培养学生创新精神与实践动手能力的重要途径。从改革实践教学方法、改进实验教学内容、加强实验教学条件和实习基地建设、抓好毕业实习和毕业论文(设计)等环节对食品科学与工程专业实践教学改革进行探讨,以期为高校食品科学与工程及相关专业开展实践教学改革提供参考。     

杂交油菜新品种扬优8号的特征特性及栽培技术

杂种优势利用是提高油菜产量水平的重要手段。为了提高油菜产量及产油量,江苏里下河地区农科所利用油菜细胞质雄性不育系,经过近十年努力,选育出杂交油菜新品种扬优8号。该品种在江苏省区试中,表现突出：产量高,一般产量可达200kg/667m2;稳产性好,参加试验的几年间产量变幅小;品质优,符合国家双低标准;抗逆性较强。是一个优秀的杂交油菜新品种。为了配合该品种的推广应用,对其相关高产保优栽培技术进行了研究,并提出了具体的栽培措施。     

基于CBL教学法的“食品工厂设计”课程教学改革与实践

CBL是近年来较为主流的一种新型的教学模式,案例是影响CBL教学效果的关键所在。CBL教学法有助于激发学生的学习兴趣,培养学生的自主学习能力和协作能力。为提高食品工程类专业的"食品工厂设计"课程教学质量,结合食品工厂设计的特点和实际情况,引入CBL教学法,精心选择案例,科学组织课堂教学,对课程进行教学改革探索,有效提高食品工程专业人才的培养质量。     

小麦抗旱的分子标记、基因定位和基因工程研究进展

综述了与小麦抗旱相关的分子标记、基因定位和基因工程研究进展。作物抗旱性是复杂的数量性状,利用分子生物学技术对抗旱相关的性状进行研究,有利于阐明其遗传基础,为进一步应用现代生物技术进行小麦抗旱性改良提供理论基础,目前小麦抗旱的分子标记尚未和育种工作紧密结合,对这种现象的原因进行了分析,提出了解决问题的办法。基因工程从渗透调节物质、Lea蛋白、转录因子3个方面进行小麦抗旱性改良,转录因子是目前转基因抗旱育种的一个发展方向。     

Anti sliding pile performance under acid stress coupling

Anti sliding piles are an important engineering structure used extensively in landslide prevention. Their durability influences their work lives. In a laboratory model experiment of a cantilevered anti sliding pile under acid stress coupling, the pile body displacement variation is monitored continuously, and both concrete strength and neutralization depth are tested. The results indicate that the concrete strength decreases gradually under acid stress coupling, while the displacement increases continuously. The neutralization depth of the concrete in the anti sliding pile is linear to the square of duration in acid stress coupling.     

Seepage Resistance and Moisture Proof of Concrete Using Electro osmotic Pulse

Seepage resistance and moisture proof of concrete structure is a hard work in civil engineering. The influence factors of seepage resistance and moisture proof of concrete using Electro Osmotic Pulse (EOP), such as electric voltage, water to cement ratio of concrete, ion concentration in liquid phase, and pulse frequency, were analyzed. Simulating experiment of EOP used to drain water and reduce relatively humidity of concrete structure is executed. The results show that, volume of water seepage is improved due to application of EOP in concrete with increase of electric voltage, W/C of concrete, and concentration of sodium sulfate. And pulse frequency has little effect on volume of water seepage. The results are also presented that effect of dewatering and humidity reducing are remarkable when EOP is applied in concrete structure.     

Stepwise Decomposition Algorithm Research of the Intersecting Body Volume of Irregular Polyhedrons

We integrate the problems of deduction of intersecting grooves and bases in the constructional engineering into the problem calculating the intersecting body volume of irregular polyhedrons, and put forward the stepwise decomposition algorithm of the intersecting body volume of irregular polyhedrons based on computer graphics. The method takes advantage of the basic algorithms in the computer graphics and improves one of the algorithms which can be used to judge whether the dot is in the plane or not. By analyzing the method, we have developed the calculation formulae. Winth the segmentation function, the stepwise decomposition algorithm can be used to compute the intersecting body volume not only of the convex polyhedrons, but also the concave polyhedrons. By programming, the stepwise decomposition algorithm has been carried out, and its accuracy has been testified by a typical example.     

预应力CFRP布及预紧螺栓加固RC梁试验研究

为提高碳纤维布加固RC结构的效果及其可靠性,提出了预应力碳纤维布与预紧螺栓联合加固技术。结合在役RC梁的损伤特点及目前的RC梁加固方法,分别采用不同的碳纤维布加固技术对完整梁和破坏梁的抗弯性能进行了对比试验研究。针对目前碳纤维布张拉设备的缺陷,研发了便于现场应用的新型碳纤维布布张拉设备,分析了预应力大小对加固效果的影响。结果表明,预应力碳纤维布及预紧螺栓联合加固技术是一种更可靠的桥梁加固方法,不仅能够提高RC梁正截面的抗弯承载能力及正常使用阶段的截面刚度,而且螺栓预紧锚固碳纤维布能够很好地抑制其在混凝土表面的剥离,提高碳纤维布与混凝土表面之间粘结强度,对碳纤维布施加预应力能够充分发挥其高强性能,有效抑制混凝土裂缝开裂和开展。