Horizontal Connection Research Articles

Research on intelligent management based on expressway business integration

For the whole process business of expressway in Zhejiang Province, many deficiencies of management mechanism and technology were found, and the IOCMM concept was put forward. Based on this concept, a set of whole-process data standards has been established, and a big data platform has been built. Big data platform design principle is that is "1 brain" + "4 business applications" + "N decision support services" to realize the whole life cycle and chain management of expressways, and form an intelligent management scheme of "investment, construction, management, maintenance and transportation" of expressways.Through this platform, the information recycling, collaboration network and scientific decision-making of each project are realized, the horizontal connection, data integration and analogy of multiple projects are realized, and the mining of deep data value is realized.

Comparison and integration of simulation models for horizontal connection pipes in geothermal bore fields

The heat transfer along horizontal connection pipes in geothermal bore fields can have significant effects and should not be neglected. As practical and design-related applications require simple and efficient models, we investigate suitability of different models for the first time within this context. Three ground and three pipe models of different complexity are studied. All model combinations are coupled with a fixed ground load boundary condition on one side and a borehole heat exchanger (BHE) model on the other side. Models are tested under a variety of realistic conditions to evaluate performance. The investigations show that all investigated pipe models are equally suitable for the application. For the ground models, the horizontal finite line source model and the numerical 2D model produce identical results for homogeneous ground properties. The soil resistance model neglects the temperature accumulation in the ground and thus leads to considerable deviations and should be avoided. Based on the findings, we propose a computationally efficient approach using a novel combination of established simple steady-state models for the BHE and connection pipes. In the selected example scenario, the consideration of a 30 m connection pipe attached to the BHE leads to an increase in the BHE load by 40% for the heating case and a reduction in the BHE load by 5% for the cooling case.

Finite Element Analysis of Hysteretic Behavior of Superposed Shear Walls Based on OpenSEES

The superimposed slab shear wall has been found to be more and more applicable in the building construction industry due to its building industrialization superiority. The hysteretic behavior of superimposed slab shear walls accounts for an important part of seismic performance analysis. This paper presents the results of a numerical study to investigate the hysteretic behavior of superimposed slab shear walls. Different calculation methods of the shear capacity of the combined interface and horizontal connection are introduced. The calculated results show that the shear capacity of the combined interface and horizontal connection is much larger than the ultimate shear capacity of a superimposed slab shear wall. Therefore, the bond slip effect of a combined interface and horizontal connection can be ignored in finite element analysis on the premise of it not affecting calculation precision. Three different theoretical analysis models, namely the vertical multi-line element model, bend–shear coupled fiber model and layered shell element model, were established in OpenSEES based on a macro-model and a micro-model. The results show that the calculated results of the vertical multi-line element model and the bend–shear coupled fiber model agree reasonably with the experiment results, whereas the calculated results of the layered shell model gave a relatively larger initial stiffness.

Seismic performance of cruciform bolted joints with various reinforcing details in modular steel construction

Extensive research has been done on exterior T-shaped joints of modular structures. The modular structure consists of stacked modules that are not only connected vertically but also need to be connected horizontally. The horizontal connection between modules is another key for the modules to form an integral structure and resist lateral forces. This paper proposes a novel bolted joint that can be applied to multi-column module internal and external connections. By designing special loading supports, three internal cruciform joints and three external cruciform joints of the modular structure were tested under column end loading. The effects of different strengthening measures and the ratio of beam to column flexural bearing capacity on the seismic performance of the joints were compared. The results showed that all the joints had good seismic performance and satisfied the requirements of SMF systems in terms of inter-story drift ratio. The stiffness and bearing capacity of the internal joints after the beam-beam combination increased by 33.2% and 17%, respectively. However, the stiffness and bearing capacity of the cruciform joints strengthened by the cover plate are not significantly improved. For joints that meet the conditions of strong columns and weak beams, modular beams can reach full-section plasticity and can meet the requirements of full-strength joints.

Study on Lateral Distribution Coefficients of Hollow Slab Bridges After Reinforced by Pasted Steel Plates

This paper adopts a new method of pasting steel plate to restore the transverse connection of hollow slab bridge, so that the strengthened bridge can meet the requirements under the state of serviceability. The original beam of the concrete hollow slab with a span of 8m from the Suizhong to Shenyang section of Jing-Shen highway was reinforced by a method of pasting steel plates. In the test the eccentric load condition was loaded and the abaqus software was used for numerical calculation after the reinforcement. Based on the theory of load transverse distribution coefficient of bridge structure, different calculation methods were used to obtain the transverse load distribution coefficient of the strengthened test beam, and it is verified that the hinged plate method can be used to calculate the hollow slab beam strengthened with steel plate. In addition, combined with previous calculations, test results and numerical analysis, this paper discusses the restoration effect of the new type of pasted steel plate reinforcement method on the bridge lateral connection. The results show that the hinged plate method can be used to calculate the load lateral distribution coefficient of hollow slab beams strengthened by pasted steel plates. therefore, the pasted steel plate reinforcement method can effectively restore the horizontal connection between the hollow slabs and meet the use of bridge structures.

연결성 관점에서 본 수학과 교육과정 국제 비교·분석 연구: 한국, 싱가포르, 홍콩을 중심으로

The purpose of this study This study aimed to analyze the curricula of Korea, Singapore, and Hong Kong from the perspective of connection — one of the competences of the 2022 national revised mathematics curriculum — and to suggest theoretical ideas for the Korean curriculum. The curricula were divided into three categories, and the criteria for the classification of connection were set into four categories: horizontal and vertical connections in terms of mathematical internal connection, connection through other subjects, and real life in terms of mathematical external connection. The analysis showed that none of the three countries revealed horizontal connections in goals and characteristics. Regarding achievement standards, horizontal connections did not appear in Korea; moreover, this was the case for vertical connections in Singapore as well as vertical connections and connections through other subjects in Hong Kong. All types of connections were reflected in teaching, learning, and assessment, with the exception of Hong Kong’s horizontal connection. Therefore, Korea needs to stipulate internal connections in goals and characteristics, reflect horizontal connections in achievement standards, and specify vertical connections in teaching, learning, and assessment. Moreover, specific methods were discussed for Singapore and Hong Kong.

Research on design and mechanical behavior of a new horizontal connection device of prefabricated shear wall

The mechanical properties of the connection joints/horizontal joints of the fabricated shear wall structure play a vital role in the fabricated structure. In order to improve the seismic performance of the fabricated shear wall structure, a new type of assembled shear wall horizontal connection device is designed and developed based on the principle of energy dissipation in this study. Two horizontal connection devices with different bolt number are designed and manufactured. The device comprises of high-strength bolts and Q345 steel. The dynamic mechanical behaviors are tested for the horizontal connection device under different sinusoidal loading frequencies. The influence laws of different bolt preload, loading frequencies and bolt numbers are explored on the mechanical properties of the device. The effect of friction temperature rise on the mechanical properties of the device is investigated. The experimental results indicate that the device can not only ensure the reliable connection of the structure, but also dissipate significant seismic energy by the internal friction of the device, so as to effectively reduce the seismic response of the structure and protect the main structure. Additionally, the energy dissipation capacity and secant stiffness of the device is proportional to the bolt preload, but the equivalent damping ratio is independent of the preload; the mechanical properties of the horizontal connection device hardly depend on the loading frequency; the increase of the bolt number can considerably enhance the energy dissipation of the device; Both the preload and loading frequency are important factors affecting the temperature rise of the device, but the temperature change has little effect on its mechanical behaviors.

A Numerical Study on the Seismic Performance of a Horizontal Dry Connection for Precast Concrete Shear Walls

Dry connections primarily consist of high-strength bolts and steel plates. They are commonly used in precast structures as they maximise time efficiency in the assembly stage compared with conventional methods. In this study, an embedded horizontal dry connection was developed using a square-shaped ring connector, high-strength hex nuts and flat washers, and grout for assembling precast concrete shear walls. Using Abaqus CAE 6.14, a numerical study was conducted on two full-scale RC shear walls including one monolithic and one precast specimen to assess the seismic performance of the bolted connection under the combined effect of axial and fully reversed cyclic loading. The average displacement ductility ratio of the precast specimen integrating the bolted connection was three times as much as the reference specimen. However, its relative energy dissipation capacity and shear strength were 21.94% and 27.92% lower, respectively. A parametric study was also carried out on the thickness and grade of the ring connector, grade of the vertical steel bars, number of ring connectors, and diameter of the vertical steel bars at the connection joints. Results showed that the seismic performance of the bolted connection was highly dependent on the bar diameter and number of ring connectors.

Effect of horizontal connection pipes on operation of borehole heat exchangers under different climatic conditions

We investigate the effect of horizontal connection pipes in shallow geothermal systems attached to a borehole field for the 25 most representative climate zones across the World. For this we use a comparable 30m connection pipe buried at 1m depth connected to a 100m deep borehole heat exchanger (BHE) as the unit representation of the whole system for all locations. The system is considered monovalent with weather dependent loads derived from local air temperatures. The connection pipes and BHE are modeled using thermal resistances and response functions. In the investigated reference scenario, the consideration of the connection pipes leads to an average reduction in BHE load of 34% in tropical climates, 19% in temperate climates, 11% in arid and 4% in continental climates, leading to a significant drilling cost reduction. Exceptions were the cities of Moscow and Heihe both located in continental climates and under severely colder conditions, where the BHE load increased by 13% and 72% due to consideration of the horizontal connection pipes, leading to a reduced efficiency or the need for additional drilling only for these cases.

Investigation of the Global Structural Behavior of the Prefabricated Shoring System Considering Structural Details

This study aims to investigate the structural behavior and load-carrying capacity of prefabricated shoring systems. The structural behavior and performance of shoring systems are influenced by the buckling of vertical members, where the compressive force acts as the main load. The buckling strength of a vertical member is sensitive to not only the material and geometrical properties of members but also the connection details between members, presence or absence of braces, and stiffness ratio between members. Therefore, in this study, the structural behavioral characteristics of the individual post member and the entire system are investigated by considering the structural details through eigenvalue and nonlinear finite element analyses. On the basis of the analytical studies, it was confirmed that the boundary condition of the vertical member, rotational and horizontal stiffnesses, and eccentricity condition of the end, which are directly affected by the compressive force acting on the prefabricated shoring system, have a direct effect on the elastic buckling strength. In addition, it was determined that factors such as whether the braces were installed, rotational stiffness of the vertical–horizontal member connection, and the number of installation stages affected the overall strength of the structure. According to the structural analysis results, the assembled structure was reduced by 92.9% and 82.2% compared to the elastic buckling strength of a single member as the height increased to two and three stories. In addition, when the bracing member was not installed, 12.1% and 23.6% strength reduction was confirmed as the elastic buckling strength increased by two and three stories compared to the case where the bracing member was installed. Consequently, the necessity of a whole structural performance evaluation technique was confirmed for a more practical structural performance evaluation.

Delegating migration control to local welfare actors: Reporting obligations in practice

Most research on the social policy–migration control link focuses on indirect control, that is, denying access to welfare. This article instead draws attention to how welfare institutions are made directly involved in migration control through duties to report certain categories of migrants to migration authorities. We ask how these obligations are put into practice and how local governments shape this process. In so doing, we place special emphasis on local organisational fields – that is, the close horizontal connection between public and non-public actors involved in basic needs provision. The article builds on exploratory research across four German cities, drawing on 61 interviews conducted in 2019–2020 with welfare actors catering to basic needs (housing/shelter, healthcare, social assistance, social counselling) and document research. Based on this, we, first, explore patterns of reporting practices and provide a typology of different responses, ranging from elaborate circumvention strategies to over-compliance. Second, we analyse the domino effects of reporting obligations, namely how welfare actors that are exempted from reporting adopt their practices too, with consequences both for migrants' welfare access and for other authorities' ability to report. Finally, we discuss how local governments can shape reporting practices, demonstrating how some cities actively sanction circumvention strategies. The last part identifies venues for further research.

Seismic Behavior of Assembly Joint with CFST Column and H-shaped Steel Beam

Existing concrete-filled steel tubular (CFST) structures are mostly based on cast-in-situ concrete construction technology. The beam-column joint emphasizes the horizontal connection, while the vertical connection of columns is mostly based on a steel tube connection instead of a precast CFST column connection; this is detrimental to the control of the concrete pouring quality and the full assembly of the structure. Thus, the investigation of an assembly joint that enables the full connection between the beam and CFST column is the key to the improvement of the construction quality and the promotion of the development of the assembled structure. This work proposes an assembly joint between an H-shaped steel beam and a CFST column, and the seismic behavior of the joint was investigated by low-cycle loading experiment. The finite element model of the joint was then established by the numerical analysis method. After verifying the rationality of the finite element model, the influences of both the endplate thickness and the bolt diameter on the energy dissipation performance of the joint were investigated via parametric analysis. The results reveal that with the increase of the endplate thickness and the bolt diameter within a certain range, both the bearing capacity and energy dissipation capacity of the joint will be improved. Moreover, the cooperative bearing mechanism of the column connector and concrete can be fully exerted. Thus, these conclusions indicate the feasibility of the use of the proposed assembly joint in practical engineering applications. Finally, the mechanical mechanism of the assembly joint was studied, and the calculation formula of the joint bending capacity was proposed.

Distributed parameter modeling for prefabricated wall-frame system assembled by horizontal and vertical connection

Distributed parameter model (also referred to as continuum model) is commonly used to analyze the behavior of conventional frame-shear wall structure. In recent decades, extensive research has been published and proved the well-controlled seismic performance of wall-frame system, beyond which some researchers applied the continuous philosophy to the analysis of specified wall-frame systems. This paper extends the distributed parameter model to a general distributed parameter model, and corresponding closed-form solutions for three typical load cases are derived, verified, and parametric analyzed. The model in this paper unifies the three nondimensional parameters into one model and parameterizes the relative stiffness between wall, frame, vertical connection, and horizontal connection. Additionally, the proposed model can analyze the system with various horizontal connection (hinged/fixed/semi-rigid) as well as vertical connection (dampers/coupling links). Further, the shear demand of frame retrofitted by resilient wall, a new retrofit has been constructed lately, is theoretically studied using the proposed model. Results shows that the shear demand of frame at upper floor levers may increase after retrofitting.

Object Detection Algorithm Based on Improved Feature Pyramid

Feature pyramid network is widely used in advanced object detection. By simply changing the network connection, the performance of small object detection can be greatly improved without increasing the amount of calculation of the original model. However, the algorithm still has some shortcomings. Therefore, a new attention feature pyramid network (attention PFN) is proposed. Firstly, an improved receptive field module is added, which can make full use of global and local context information. Secondly, the connection mode of the pyramid is further optimized. Deconvolution is used to replace the nearest neighbor interpolation in top-down up-sampling and a channel attention module is added to the horizontal connection to highlight important context information. Finally, adaptive fusion and spatial feature balance are used for each feature pyramid, so that the network can learn the weights of different feature layers. Each pyramid layer contains more discrimination information. Attention PFN is tested on Pascal VOC and MS COCO datasets, respectively. The experiment results revealed that the proposed method has better performance than the original algorithm. Therefore, the attention PFN is an effective algorithm.

HFENet: Hierarchical Feature Extraction Network for Accurate Landcover Classification

Landcover classification is an important application in remote sensing, but it is always a challenge to distinguish different features with similar characteristics or large-scale differences. Some deep learning networks, such as UperNet, PSPNet, and DANet, use pyramid pooling and attention mechanisms to improve their abilities in multi-scale features extraction. However, due to the neglect of low-level features contained in the underlying network and the information differences between feature maps, it is difficult to identify small-scale objects. Thus, we propose a novel image segmentation network, named HFENet, for mining multi-level semantic information. Like the UperNet, HFENet adopts a top-down horizontal connection architecture while includes two improved modules, the HFE and the MFF. According to the characteristics of different levels of semantic information, HFE module reconstructs the feature extraction part by introducing an attention mechanism and pyramid pooling module to fully mine semantic information. With the help of a channel attention mechanism, MFF module up-samples and re-weights the feature maps to fuse them and enhance the expression ability of multi-scale features. Ablation studies and comparative experiments between HFENet and seven state-of-the-art models (U-Net, DeepLabv3+, PSPNet, FCN, UperNet, DANet and SegNet) are conducted with a self-labeled GF-2 remote sensing image dataset (MZData) and two open datasets landcover.ai and WHU building dataset. The results show that HFENet on three datasets with six evaluation metrics (mIoU, FWIoU, PA, mP, mRecall and mF1) are better than the other models and the mIoU is improved 7.41–10.60% on MZData, 1.17–11.57% on WHU building dataset and 0.93–4.31% on landcover.ai. HFENet can perform better in the task of refining the semantic segmentation of remote sensing images.

Exploring the New Mode of Teaching Computer-Aided Environmental Art Design Courses

Environmental art design course is the main direction of practical teaching. Therefore, the teaching reform and practical research of environmental art design based on CAD have been carried out. Innovative environmental art design courses, taking into account the differences of student groups, formulate the teaching methods of introductory courses, formulate the comprehensive topics of curriculum design, expand the knowledge base, improve the professional curriculum system, and strengthen the horizontal connection between curriculum teaching and computer design to meet the diversified needs of different student groups. Environmental art design also requires that before formal construction, with the help of computer-aided function, establish architectural drawings and analyze the rationality of each construction process. In view of the current situation and further development prospect of computer-aided application design, designers should improve the application level of graphics software. This paper is mainly committed to optimizing environmental art design teaching through computer, making full use of artificial environment design, improving the efficiency of computer performance technology, avoiding too single final design effect, so as to enhance the appeal of ecological art and meet people’s aesthetic needs.

On influence of structural features on stress-strain state of a reinforced concrete floor slab

Introduction. An assessment of the influence for the type of bonds and the magnitude of the prestress of the longitudinal working reinforcement on the stress-strain state of the reinforced concrete floor slab, developed by the authors was made. Materials and methods. The studies on a finite element model of a reinforced concrete floor slab, implemented in LIRA software package were carried out. Results. The development of stress values and transverse vertical displacements directly depended on the support conditions of the floor slab. Limitation of transverse horizontal displacements on the support by any of the selected methods made it possible to reduce stresses by 3.47 - 3.78 times, deflections by 1.5 - 1.52 times, stresses - up to 11.9 times, w ребро deflections - 1.18–1.53 times. Creating an end rib or limiting movement with an additional horizontal connection had almost the same effect. The transverse horizontal displacements of the lower face of the longitudinal contour rib in the direction of the 𝑢 ребро span which occurred in the floor slab, which did not have an end rib and limitation of displacements in the transverse direction, were in a parabolic relationship with the magnitudes of the vertical transverse forces. In a florr slab with limited displacements in the transverse direction or with an end rib, 𝑢 ребро displacements were 3.88–4.32 times less, and at the ends they depended on the deformability of the bonds, i.e. when horizontal movement was prohibited, they were equal to zero. stresses acting on the lower edge of the flange in the transverse direction, in the region of the middle of the span in the floor slab with reinforcement prestressed to the maximum value, had positive values almost over the entire width of the flange and directly depended on the thickness of the slab in each section. Prestressing made it possible to reduce deflections by 4.02 - 4.37 times, w ребро deflections by 1.09 - 5.59 times, and evenly distribute stresses along the length of the longitudinal contour rib, to make they are only tensile, close to zero along its entire length. The prestressing of the reinforcement of the maximum value made it possible to increase the horizontal rigidity of the longitudinal contour rib of the floor slab and limit its transverse 𝑢 ребро movements. The transverse displacements that occurred near the support of the prestressed shell slab were 1.04 - 1.2 times less than in the shell slab with non-stressed reinforcement, on the rest of the span - slightly more, changing evenly, without sharp changes, unlike floor slabs with non-stressed reinforcement. Discussion and conclusion. It is established that the optimal design of the floor slab under the study should have restrictions on the movements of the supports and the maximum possible prestressing of the longitudinal working reinforcement. The practical significance of the study is that the specified reference conditions and prestress allow maximum deformation resistance of the structure, which in our case directly affects the bearing capacity of the slab.

Research on Manufacturing and Construction Technology of 50m Steel Box Girder

In the construction of 50m steel box girder of Chengdu Tianfu Airport Expressway, in order to overcome the difficulty of making long steel box girder, China Tieshan Bridge first manufactured the plate unit in the Chengdu base factory, and then assembled the beam section, and transported the large piece for 28km. The steel beam in this project is an I-shaped structure, and each beam section is composed of a bottom plate, a web plate, a top plate, a horizontal connection and a cantilever arm. In the manufacture of beam sections, the actual assembly of each bridge steel plate girder is that each section is pre-assembled on the same tire mold frame, and the assembly iscarried out in sequence from the middle to the two sides, and the size error is controlled by the form of temporary matching between the blocks. And the overall linearity, to ensure the quality.

Organizational and legal issues in streamlining the horizontal structural connection between central and local public bodies

The article reveals the reasons for the lack of coordination functions and horizontal links in the apparatus of public authorities in the Republic of Moldova. The object of the research is a complex of legal and non-legal relations, multiparty, which arise in the initial stages of the formation of unstable organizational structures, linear-functional, of the central public administration bodies. The aim of this paper is to develop methods for streamlining the relationships and structures of the functional matrix at all levels of governance and self-government. Ways to weaken the multiparty factor are proposed by developing self-regulatory organizations of entrepreneurs and delegating them to state functions. The relevance of the topic is due to the fact that the lack of flexible links and coordination structures between the governing bodies, in the conditions of constant conflicts between party leaders, can lead to problems that call into question the very existence of the state. The author also argues that concrete measures need to be taken in order to combat imperfect legal rules in the form of tightening control over departmental regulation and establishing a permanent review of legislation. Based on the author’s experience in using the various questionnaires and surveys in his monographs, it is proposed, in drafting each new bill, to conduct a content analysis of current regulatory acts in the relevant field or industry and, from a scientific point of view, reach a final decision on whether such a regulatory act can be adopted. It is proposed to formulate at the state level and include in the legislation the various strategic objectives of promoting cooperation in the field of scientific and technological progress and small business.

Anti-collapse behavior of modular steel buildings with corrugated panels

This paper numerically studies the anti-collapse behavior of the modular steel building (MSB) in the scenario of interior module removal and corner module removal. The vertical displacement, lateral displacement and internal force of a six-storey MSB in a sudden module loss are studied. The reasonability by using rigid body assumption in collapse analysis of the MSB is examined. A refined fracture model of the steel is incorporated into ABAQUS via user subroutine, in which the effects of both stress triaxiality and Lode angle on the fracture ductility of the steel are considered. In the pushover analyses, the effects of the horizontal connection, opening of the wall panel and thickness of the wall panel on the collapse resistance and failure mode of the MSB are studied. The dynamic amplification factor (DAF) of the MSB at the collapse limit state is also obtained. It is found that the rigid body assumption may significantly underestimate the displacement and maximum shear force in the horizontal connection of the MSB. Two types of failure modes of the structure are observed, namely, connection failure-induced collapse and module unit failure-induced collapse. Among the studied parameters, the effect of the opening size of the wall panel on the behavior of the structure is the most significant. In the scenario of the interior module removal and corner module removal, the DAFs of the structure at the collapse limit state range from 1.20–1.29 and 1.27–1.50, respectively.