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The paper presents the results of computational analysis of the stress-strain state of reinforced concrete spans of the railway (single-track railway line) overpass over the highway, under specified loads using spatial finite element models. The static load consists of a cohesion of three TEM-18 diesel locomotives and two loaded gondola cars (up to 25 tons per axle). The purpose of this study was to ensure reliable and safe operation of artificial structures on the railroads, as there is a constant increase in transit freight trains from China through the territory of Kazakhstan to near and far abroad, and often the load on the axle reaches 25 tons, and sometimes larger values – up to 27 tons per axle. The results of the study are recommended to be used for inspections and tests of typical girder bridge spans, as well as in the case of monitoring their technical condition with increasing operational loads. [ABSTRACT FROM AUTHOR]

The purpose of this paper is to investigate the capabilities of the inexpensive theodolite created by the authors, compared with modern commercial instruments, equipped with a Leica TPS1203 robotic total station with built-in GoPro Hero6 camera image sensors. This theodolite was tested in the laboratory where simulated dynamic displacements were determined. The results of the experimental tests showed that the displacement errors and differences between the simulated displacements of the test machine and those detected by the theodolite were in the range of Δ = − 0. 1 5 mm to +0.13 mm depending on the simulated amplitude. The theodolite was further used in the field for static and dynamic tests of the Wanzhou Railway Bridge, China. Determination of the dynamic motions of the bridge and the results of calculating the natural frequencies from the measurement data are presented. During loading tests of the bridge, the frequencies were also determined by accelerometers and these data were used as a reference to assess the accuracy of the theodolite and its suitability for dynamic tests. An original algorithm was developed in the MATLAB software environment to process the recorded videos, i.e. image processing to determine displacements and natural frequencies. It is demonstrated that the position of the theodolite at a distance of 28.5 m from the bridge provides the correspondence of one pixel of 0.333 mm, which provides a high level of accuracy when determining the dynamic vertical displacements of a moving target. It is established that the proposed theodolite will cost less than 5 000 euros. The results obtained are relevant for use in civil engineering for monitoring the amplitude vibrations of structures. [ABSTRACT FROM AUTHOR]

• Two phases of deformation occured in the south of the Shangdan suture zone across the Mianyuzui ductile strike-slip fault. • The metamorphic temperature of the early stage of shearing deformation is ∼ 600-700℃ and ∼ 300-500℃ for the late stage. • The subduction of the Shangdan Oceanic lithosphere was active till the Early Silurian, and subsequent collisions occurred during the Late Silurian. The Shangdan suture zone (SDSZ) subdivides the Qinling Orogenic Belt into North Qinling and South Qinling belts, marking the main tectonic boundary between the North China and South China Blocks. The Mianyuzi ductile strike-slip fault (MYZF) within the SDSZ separates the North China Block from the South China Block and contains valuable collisional information. This paper integrates the structural and geochronological data of the MYZF to investigate the Paleozoic tectonic evolution of the Qinling Orogenic Belt and the collision between the North China and South China Blocks. Two phases of deformation (D 1 -D 2a-b) are identified along the southern boundary of the SDSZ. The metamorphic temperature of mylonites is ∼ 600–700 ℃ for the early stage and ∼ 300–500 ℃ for the late stage of shearing deformation. U-Pb zircon analysis of the mylonites and diabase dike in the ductile shear reveals that zircons have major younger protolith populations at 480–460 Ma, 450–430 Ma, and 405–425 Ma, which suggests that rocks were probably derived from the North Qinling belt. The metamorphism and deformation cooling age from the MYZF have been constrained to be 339–328 Ma and 259 ± 1.6 Ma using U-Pb and 40Ar/39Ar dating. Combined with previously published data, we concluded that the subduction of the Shangdan Ocean was active until the Early Silurian and subsequent collisions occurred during the Late Silurian. Meanwhile, the shearing might have been related to the intraplate extension-exhumation during the Carboniferous-Late Permian in the Qinling Orogenic Belt. [ABSTRACT FROM AUTHOR]

Experiment was carried out to explore the effect of compression treatment to garlic (Allium sativum L.) cloves on emergence and growth of garlic. White garlic cloves of Northeastern China were compressed at transverse and longitudinal direction to the degrees of 5%-45% and planted, the untreated garlic cloves were used as controls. The effects of different degrees of compression on emergence time, emergence rate, plant stalk diameter and plant height for cloves were investigated, and the regression models of plant stalk diameter with the degrees of compression for cloves were obtained. Correlation analysis between garlic plant height with degrees of compression was carried out. The results showed that, compared with the control, for cloves compressed at transverse direction, the compression levels of 10%-45% had significant effect on emergence time, emergence rate, plant stalk diameter and plant height (P<0.05), the treated seeds emerged earlier; the emergence rate, stalk diameter and plant height of cloves at compression of 10%-25% were greater than that of control. For cloves compressed at longitudinal direction, the compression of 10%-45% had significant effect on emergence time, emergence rate, plant stalk diameter and plant height of garlic (P<0.05); the treated cloves emerged later; the emergence rate and stalk diameter of cloves at compression of 10%-15% were greater than that of controls. It can be concluded that compression at transverse direction of clove is favorable for the growth of garlic than compression at longitudinal direction and the optimal rate of compression is 10%-25%. Regression equations of plant stalk diameter with the degrees of compression for cloves fit well (R≥0.91)with the test data, and the correlativity between the degree of compression and garlic plant stalk diameter is extremely significant (P<0.01). [ABSTRACT FROM AUTHOR]

This paper presents the results of the dynamic finite element analysis of the Hong Kong–Zhuhai–Macau immersed tunnel, conducted to study the effects of the random soil properties and the wave passage effect. According to the results of the free-field analysis, it was found that the wave passage effect could decrease peak ground acceleration (PGA) and causes a time lag in wave arrivals. Conversely, the random soil properties enlarge PGA sharply. The ‘low-frequency amplification, high-frequency filter’ phenomenon also occurs. The results of the structural dynamic analysis indicate that the soil properties and the wave passage effect have a significant influence on dynamic responses of the immersed tunnel. Although random soil properties only alter bending moments slightly, it can enlarge axial forces by up to 230% and the deformations of Gina gaskets. The wave passage can increase bending moments, Gina gaskets deformations and especially axial forces. The inertial force is the main cause for the sharp increases in axial forces. The combined effects of the random soil properties and the wave passage effect are remarkable. In some cases, Gina gasket deformations will exceed their upper and lower limits of compression, raising the possibility of joint failure and leakage. Thus, it is necessary to consider the influences of the random soil properties and the wave passage effect when conducting a practical seismic design. [ABSTRACT FROM AUTHOR]