Applied Mechanics and Materials Vols. 99-100

Abstract: Recycled fine concrete aggregate can not be directly used for concrete for its large water absorption, so we get recycled concrete powder through grinding process, and carried out series experimental studies on the recycled concrete powder. The results show that the technical parameters of recycled concrete powder can achieve the requirements of S95 grade slag powder. The slump constant of recycled concrete mixed with recycled concrete powder is slightly less than slag concrete,while cohesiveness and water retention is better than slag concrete. Replace slag powder with recycled concrete powder, the recycled concrete has high early strength but post-intensity does not change significantly. Recycled concrete powder replacement slag powder does not reduce the impermeability, frost resistance and carbonation resistance of recycled concrete. The conclusion shows that recycled concrete powder can completely replace slag powder in concrete to realize full efficiency reuse of waste concrete.

Abstract: Succade wastewater, which was produced in manufacturing process, was treated with two kinds of coagulating agents PAC and ferrous sulfate. The influences of pH, concentration of coagulating agent on COD value, turbidity have been studied. The results of the experiments have shown that for ferrous sulfate, there is an obvious positive correlation, but no significant relation with turbidity removal rate was presented in the statistics; As for PAC, the turbidity declined significantly as PAC dosage increases, only when pH=5 that COD removal rate shows a clear positive correlation with PAC dosage.

Abstract: Green high performance alkali-activated slag pavement concrete(ASC) was prepared by adding Na2SiO3 and NaOH complex activator in slag. Physical, mechanical performance and durability of ASC were studied by workability, strength, hydrostatics and chlorin ion penetrability, fast freeze-thaw cycle tests and abrasion resistance tests. The results show that slump of ASC exceeds 160mm, fluidity and workability is excellent. 28d compressive and flexural trength of AAC are 91.9MPa and 8.5MPa, 7d compressive and flexural strength are 84.8MPa and 7.6MPa, which belongs to high–early strenth concrete. And its impermeability rank exceeds S40, chlorin ion impermeability is excellent, 6h eletricity is 1751～1894 coulomb, and its anti-frozen rank exceeds F300, which can meet the anti-frozen requirements in frore area. Depth of abrade slot is 0.45～0.96mm, abrasion resistance of ASC is 4.99, so its physical, mechanical performance and durability are superior to traditional portland concrete.

Abstract: Abstract: The application of curved surface is more and more popular in various kinds of engineering, for different curved surfaces ,because the form and formation way of their generatrix form are different, the surface properties are also different[1,2],so the relevant materials used must match with them too. As a designer, when he/she designs the curved surface, while in pursuit of the perfect modeling, he/she must take the scientific structure in consideration as well, so as to convenient for construction; As a constructor, he/she must fully understand the curved surface’s character, rasp the mechanism, and then use a scientific and simple technique to achieve a perfect structure modeling.

Abstract: Based on the test data of twelve push-out specimens with different holes filling different materials,the paper compared and analyzed the capacity and the corresponding slip value of the stud shear connector. The results show that, as to the two different kinds of holes shape ,the strength of the stud shear connectors of square push-out specimens was huger than that of circular specimens with the same condition; the strength of stud shear connectors in steel-concrete composite structure was decided by the strength of concrete surrounding the shear in the holes, with increasing concrete strength, the strength of stud shear connectors improved greatly; The outputs of this study are very useful for further understanding of the characteristics of the stud,it is also expected that the results presented in this paper should be valuable for the design of the composite beams.

Abstract: Based on cybernetics, feedback and other theories, the paper first introduces something about the learning system and then puts forward a new learning method-active input and active output method. In connection with the current problem of college students’ not very high learning efficiency, this paper, with college students as the subject of study, cybernetics as theoretical basis and experiment as verification means, makes a deep study on the factors influencing the language output of Chinese college students, puts forward the English learning model of active input and active output. The research indicates that in the current non-immersion learning environment, the active input and active output leaning theory will not only help learners to form new acquisition of language, improve comprehensively their discourse behavior, but also to spur on learners to make use of all their resources to improve their communicative competence. College students, who adopt such learning methods, show a higher enthusiasm and stronger confidence in studying English.

Abstract: Based on Vb programming language, combined with the large span suspension bridge in the project construction management, research and development of a visual simulation of integrated system platform, achieve the data call and control on the dynamic 3D visual simulation model. Ready to deal with various types of data required for the project, and fundamentally changes the method of mass data management, to realize the “visualization”, “specification” and “simplification” of modern construction management, so that all results more intuitive display of data in the dialog window with visual modeling. It’s good call on a variety of data to guide construction.

Abstract: Dynamic stress concentration of tunnels and underground engineers under the action of earthquake waves is a fundamental problem. Selecting circular lining tunnel in semi-infinite space under the action of P waves as prototype, based on the assumption of large circular arc, a set of dynamic stress series solution in semi-infinite space and lining is deduced by wave function expansion method. With specific examples, the influences on shallow-buried depth rock tunnels of different factors which include incident frequency, incident angle, buried depth, rock conditions and lining rigidity are studied. The results show that low-frequency P waves are more dangerous to tunnel lining than high-frequency P waves; When P waves is incident from the bottom of the vertical tunnel or small angle (θα = 0° ~ 30°), the damage of tunnel lining is more seriously; Under the hard rock conditions, when the tunnel buried depth reaches more than 100m, the thickness of overlying rock is not a major factor effecting the dynamic stress and earthquake damages of tunnel structure lining; Under the soft surrounding rock condition, the value of dynamic stress concentration coefficient of lining is still up to 6.5 when the buried depth of tunnels is more than 100m, and what’s more the tunnel lining may still be caused seriously earthquake damage; With the increasing of lining stiffness, the dynamic stress concentration of lining is more uneven, and the value span is greater; so under the premise of meeting bearing capacity and deformation of lining, soft lining is recommended to adapt in the tunnel structure to decrease earthquake damage of tunnels.

Abstract: This article introduces fuzzy mathematics and comprehensive assessment in campus architecture safety assessment, this method can help to make an effective multi-factor decision in campus architecture safety assessment, making the assessment result more objective, rational and effective. Dalian jiaotong university comprehensive teaching building which finished in Port of Lushun campus is selected at the end of the article to explain the whole process of the application of fuzzy mathematics and comprehensive assessment in campus architecture safety assessment.

Abstract: Charge weight is an important consideration when calculating for the blasting crater. The main parameters affecting the blasting crater are the rock type, minimum amount of chemicals consumed, and resistance lines. Although only a few parameters influence the blasting crater, calculating and speadsheeting require a large amount of work and furnish results that are not intuitive. Moreover, the calculation of blasting crater parameters takes time. The current study calculated the parameters using Visual Basic to illustrate a fast spreadsheeting and mapping method using Computer-Aided Design, the design for the charge until the supporting role.