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Study on Bonding Performance Between Overlay Layers of Polymer Modified Asphalt Mixture
Issue:
Volume 8, Issue 5, October 2020
Pages:
79-82
Received:
28 July 2020
Published:
23 September 2020
Abstract: The asphalt mixture thin overlay is usually paved on the basis of the original pavement sprayed with modified asphalt tack coat oil, and the paving thickness is generally controlled within 2-3cm. The thin overlay has the advantages of high strength, good durability, good skid resistance, fast construction speed, high efficiency and short open traffic time. It can effectively solve the problems of slight cracks, skid resistance, shallow rutting, water seepage and aging of pavement. Because the paving thickness of the thin overlay is only 2-3cm, it is difficult to guarantee the bonding force between the overlay and the original pavement layer, which is easy to appear the phenomenon of shear slip between the overlay and the original pavement layer under the load of vehicles, so the interlayer bonding between the overlay and the underlying layer is particularly critical in practical application. This study uses polymer modified asphalt provided by Nanjing limiqing New Material Technology Co., Ltd. in this paper, the bond performance between asphalt concrete and original pavement is tested by pull-out test to verify the bonding performance of the interface, which lays a foundation for the application of thin-layer overlay of asphalt mixture.
Abstract: The asphalt mixture thin overlay is usually paved on the basis of the original pavement sprayed with modified asphalt tack coat oil, and the paving thickness is generally controlled within 2-3cm. The thin overlay has the advantages of high strength, good durability, good skid resistance, fast construction speed, high efficiency and short open traff...
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Seismic Design of a Out-of-code High-rise Library
Issue:
Volume 8, Issue 5, October 2020
Pages:
83-89
Received:
11 August 2020
Published:
23 September 2020
Abstract: In order to meet the requirements of architectural design form, a high-rise library project appeared many structural seismic designs, such as plane thin waist concave, large area floor missing, tower offset and torsion irregularity. In accordance with the principle of economy, safety and reliability, many calculation measures are adopted in the structural design, such as the comparative analysis of software SATWE and ETABS, the special calculation of floor stress level, the combining floor analysis of missing floors and the strengthening performance analysis under medium and large earthquake. At the same time, according to the structural transfinite items, the structural strengthening measures are taken, such as optimizing the structural layout, reducing the eccentricity, increasing the thickness of the floor at the weak position, and adding diagonal reinforcement in the stress concentration area. Using the above treatment, the structure can meet the fortification target under three levels.
Abstract: In order to meet the requirements of architectural design form, a high-rise library project appeared many structural seismic designs, such as plane thin waist concave, large area floor missing, tower offset and torsion irregularity. In accordance with the principle of economy, safety and reliability, many calculation measures are adopted in the str...
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Dynamic Response of Membrane Structures Under Water Impact
Li Yantao,
Xu Xiaochen,
Xu Zhihong
Issue:
Volume 8, Issue 5, October 2020
Pages:
90-96
Received:
24 August 2020
Published:
23 September 2020
Abstract: In this paper, the dynamic response of ship-borne membrane radome under the impact of water was investigated.Based on smooth particle hydrodynamics (Smooth particle hydrodynamics SPH), a fluid-structure coupling model was established, to simulate the membrane structure impacted by water, and the dynamics of the shipboard radome membrane structure under the impact of the breaking wave water body are simulated by the computer numerical simulation method response.The influence of the initial velocity of water, the angle of incidence, the initial pretension of the membrane structure and the tensile shape of the membrane surface on the maximum impact deformation and maximum impact stress of the membrane surface are analyzed. According to experimental analysis, under the same impact, the film structure with greater pretension has stronger resistance to impact, that is to say, under the same impact of water body, the greater the pretension of the membrane structure, the smaller the maximum internal stress change amplitude when it is impacted. Therefore, a certain optimal prestress is found to make the entire radome membrane structure suffer the same impact. The minimum maximum membrane stress is generated at the time, so as to achieve the purpose of protecting the fabric membrane structure from large stress and deformation; at the same impact speed, the vertical impact angle has the greatest impact on the membrane structure; under the same impact and pretension, the saddle-shaped film surface has stronger resistance to impact than the flat film surface.
Abstract: In this paper, the dynamic response of ship-borne membrane radome under the impact of water was investigated.Based on smooth particle hydrodynamics (Smooth particle hydrodynamics SPH), a fluid-structure coupling model was established, to simulate the membrane structure impacted by water, and the dynamics of the shipboard radome membrane structure u...
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Analysis and Evaluation of Structural Safety Inspection of a Railway Station
Guo Xiaoyan,
Fang Lin,
Ma Zefeng
Issue:
Volume 8, Issue 5, October 2020
Pages:
97-100
Received:
31 August 2020
Published:
17 October 2020
Abstract: Based on the structural safety inspection of a railway station, first the current status and damage of the housing structure are introduced. It is analysed in this paper the safe capability of the railway station via precise on-site testing work. It is further discussed the influence of different modeling methods on the calculative results of the compressive bearing capacity of buttress column used in this masory structure. There is no software could accurately simulate the compressive bearing capacity of buttress column, for it is difficult to meet the actual needs of the project. This paper could be valuable future reference for the safety inspection and strengthening scheme of similar projects.
Abstract: Based on the structural safety inspection of a railway station, first the current status and damage of the housing structure are introduced. It is analysed in this paper the safe capability of the railway station via precise on-site testing work. It is further discussed the influence of different modeling methods on the calculative results of the c...
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Hybrid Simulation Study on Cooperative Deformation of Nonlinear Steel-Cable Structure
Zhang Yong,
Xu Zhihong,
Chen Jiahao
Issue:
Volume 8, Issue 5, October 2020
Pages:
101-106
Received:
8 September 2020
Published:
17 October 2020
Abstract: In this paper, a hybrid simulation test method is used to study the cooperative deformation of nonlinear steel-cable structures. The general structural deformation analysis methods include the overall structure model test method and the numerical simulation method. The overall structure model test method is costly and the process is complicated; the numerical simulation method requires high requirements and requires prior knowledge of the constitutive relationship of the structure or component. The hybrid simulation test method combines the advantages of the two, that is, the entire structure is divided into two, one part is used as a test substructure for model testing, and the other is used as a numerical substructure for numerical simulation. In this study, the nonlinear cable is used as the experimental substructure for model test, and the rest of the cable is used as the numerical substructure for numerical simulation. Through the synchronous interactive feedback of the data between the two, the combined deformation of the nonlinear frame-type steel-cable structure is gradually obtained. Finally, the results of the hybrid simulation test are compared with the results of the numerical simulation test to verify the effectiveness of the hybrid simulation test method. The research in this paper can provide a new method for the combined deformation calculation of nonlinear steel-cable structures.
Abstract: In this paper, a hybrid simulation test method is used to study the cooperative deformation of nonlinear steel-cable structures. The general structural deformation analysis methods include the overall structure model test method and the numerical simulation method. The overall structure model test method is costly and the process is complicated; th...
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Numerical Simulation Study on Influence of Multi-seam Propagation of Hydraulic Fracture in Coal Seam
Zhang Weiqiang,
Pu Chunsheng
Issue:
Volume 8, Issue 5, October 2020
Pages:
107-112
Received:
12 September 2020
Published:
17 October 2020
Abstract: Multi-stage fracturing technology for horizontal Wells is one of the effective methods of coal seam volume reconstruction at present. This technology can effectively form a volumetric seam network, increase the volume of coal seam segment reconstruction, increase the area of gas seepage channel, and reduce the generation of coal powder. In order to study the mutual interference of multi-fracture extension in hydraulic fracturing of coal seam and to solve the problem of unclear effect of fracturing construction parameters in coal seam at present, this paper, based on the extended finite element method (XFEM), conducts fluid-solid coupling simulation using pore pressure element (C3D8P), and establishes a calculation model of multi-fracture extension in coal seam. This model is used to study the influence of perforating cluster number, cluster spacing and non-uniformity on hydraulic fracture propagation. The calculated results indicate that, with the increase of the number of perforating clusters, the surface stress field is disturbed more seriously by fractures, and the volume of formation reconstruction also increases correspondingly. After comprehensive comparison, it is believed that the optimal fracturing effect can be achieved when two clusters of perforating clusters are used. The larger the cluster spacing, the smaller the inter-fracture interference, and the higher the formation pore pressure during fracturing. The non-uniformity between clusters has a great influence on fracture propagation. When the displacement of the middle cluster is 1/4, the inhibition effect is severe and it is difficult to form effective fracturing fracture. Finally, the model is used to optimize the multi-stage fracturing construction parameters of horizontal well in coal seam, which provides reference and guidance for the design of hydraulic fracturing scheme.
Abstract: Multi-stage fracturing technology for horizontal Wells is one of the effective methods of coal seam volume reconstruction at present. This technology can effectively form a volumetric seam network, increase the volume of coal seam segment reconstruction, increase the area of gas seepage channel, and reduce the generation of coal powder. In order to...
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Evaluation of Coordination and Optimal Route of Military-Military Integration Logistics System
Ying Xu,
Jiongqi Wang,
Xiaogang Pan,
Haiyin Zhou,
Zhangming He,
Bowen Hou
Issue:
Volume 8, Issue 5, October 2020
Pages:
113-121
Received:
1 September 2020
Published:
17 October 2020
Abstract: In order to promote the deep development strategy of national civil-military integration, establish a mutual coupling and coordinated development of military local logistics system, and promote the sound and rapid development of national economic development and national defense modernization, this paper studies the construction and coordination evaluation of civil-military integration logistics system from the field of logistics. This paper briefly describes the relationship between military logistics and civil logistics, at the same time, according to the current situation of domestic epidemic situation, on the basis of the military civilian integration logistics system constructed by scholars, an emergency response mechanism is added to constitute the index system and evaluation model of the coordination degree of the military civilian integration logistics system. This paper uses fuzzy analytic hierarchy process (FAHP) to analyze the new evaluation model of military civil integration logistics coordination degree, and the evaluation matrix of each criterion relative to the overall evaluation objective is obtained. According to the evaluation matrix, and puts forward corresponding suggestions and opinions aiming at the possible problems existing in the current military civil integration logistics system, so as to provide reference for the construction and adjustment of the military civilian integration logistics system by the relevant national departments in the future.
Abstract: In order to promote the deep development strategy of national civil-military integration, establish a mutual coupling and coordinated development of military local logistics system, and promote the sound and rapid development of national economic development and national defense modernization, this paper studies the construction and coordination ev...
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