scholarly journals The Study on the Construction Method of Bolting-Grouting Integrated Operation for Unmanned Arch Erection

2021 ◽  
Author(s):  
Dewu Li ◽  
Xiaotian Lei ◽  
Guowei Zhang ◽  
Mingxing Cao
Keyword(s):  
Construction Method ◽  
Structural Quality ◽  
Large Section ◽  
Manual Work ◽  
Construction Period ◽  
Construction Methods ◽  
Integrated Operation ◽  
New Type ◽  
Traditional Construction

Abstract It is of great significance to improve the mechanization level and construction quality of tunnel construction. At present, large cross-section tunnels are emerging in China. The construction method based on manual work and supplemented by a machinery has long construction period, high labor intensity, and structural quality that cannot be guaranteed. To address those issues, this paper proposes the construction method of bolting-grouting integrated operation for an unmanned arch erection to achieve the rapid and safe construction of large section tunnels and reducing the amount of manual work. This paper mainly introduces the bolting-grouting integrated operation trolley, which can achieve the automatic installation of steel arch, the construction of locking anchor pipe, and shotcrete. Besides, this paper designs a new type of steel arch and an alternative way of longitudinal connecting reinforcement of steel arch. Moreover, with the field test and optimization adjustment of the Xinwushaoling tunnel, it is found that the construction method of bolting-grouting integrated operation for unmanned arch erection can overcome some disadvantages of traditional construction methods.

scholarly journals Discussion on construction methods and precautions of building water supply and drainage

2018 ◽  
Vol 2 (2) ◽  
Author(s):  
Guoliang Yu ◽  
Fan Fan Yang ◽  
Li Li Li ◽  
Zhenfeng Zhenfeng Li ◽  
Zhenlong Shi
Keyword(s):  
Water Supply ◽  
Construction Project ◽  
Construction Method ◽  
Construction Quality ◽  
Strong Function ◽  
Construction Enterprises ◽  
Construction Methods ◽  
Quality Of Water

As an important construction link in the construction project, the quality of the water supply and drainage directly affects the overall quality of the construction project. Because of the strong function of the water supply and drainage project, the construction quality is easily affected by the construction method. For this reason, construction enterprises should attach importance to the mastery of water supply and drainage construction methods. And further understand the relevant precautions of construction water supply and drainage construction, in order to achieve the purpose of improving the quality of water supply and drainage construction. 

scholarly journals Solving Large-Scale TSP Using a Fast Wedging Insertion Partitioning Approach

2015 ◽  
Vol 2015 ◽  
pp. 1-8 ◽  
Author(s):  
Zuoyong Xiang ◽  
Zhenyu Chen ◽  
Xingyu Gao ◽  
Xinjun Wang ◽  
Fangchun Di ◽  
...  
Keyword(s):  
Traveling Salesman Problem ◽  
Time Complexity ◽  
Large Scale ◽  
Construction Method ◽  
Traveling Salesman ◽  
Experimental Results ◽  
Insertion Method ◽  
Symmetric Traveling Salesman Problem ◽  
Traditional Construction

A new partitioning method, called Wedging Insertion, is proposed for solving large-scale symmetric Traveling Salesman Problem (TSP). The idea of our proposed algorithm is to cut a TSP tour into four segments by nodes’ coordinate (not by rectangle, such as Strip, FRP, and Karp). Each node is located in one of their segments, which excludes four particular nodes, and each segment does not twist with other segments. After the partitioning process, this algorithm utilizes traditional construction method, that is, the insertion method, for each segment to improve the quality of tour, and then connects the starting node and the ending node of each segment to obtain the complete tour. In order to test the performance of our proposed algorithm, we conduct the experiments on various TSPLIB instances. The experimental results show that our proposed algorithm in this paper is more efficient for solving large-scale TSPs. Specifically, our approach is able to obviously reduce the time complexity for running the algorithm; meanwhile, it will lose only about 10% of the algorithm’s performance.

scholarly journals Discussion on construction methods and precautions of building water supply and drainage

2018 ◽  
Author(s):  
Guoliang Yu ◽  
Fan Fan Yang ◽  
Li Li Li ◽  
Zhenfeng Zhenfeng Li ◽  
Zhenlong Shi
Keyword(s):  
Water Supply ◽  
Construction Project ◽  
Construction Method ◽  
Construction Quality ◽  
Strong Function ◽  
Construction Enterprises ◽  
Construction Methods ◽  
Quality Of Water

As an important construction link in the construction project, the quality of the water supply and drainage directly affects the overall quality of the construction project. Because of the strong function of the water supply and drainage project, the construction quality is easily affected by the construction method. For this reason, construction enterprises should attach importance to the mastery of water supply and drainage construction methods. And further understand the relevant precautions of construction water supply and drainage construction, in order to achieve the purpose of improving the quality of water supply and drainage construction. 

Incremental Launching Construction Method for Steel Truss Suspension Bridge

2011 ◽  
Vol 204-210 ◽  
pp. 842-845
Author(s):  
Kai Ming Xu
Keyword(s):  
Suspension Bridge ◽  
Linear Analysis ◽  
Construction Method ◽  
Western China ◽  
Suspension Bridges ◽  
Practical Application ◽  
Construction Methods ◽  
Steel Truss ◽  
Non Linear ◽  
Traditional Construction

For steel truss suspension bridges, traditional construction methods always have their disadvantages. This paper firstly points out the limitations of the traditional construction methods (such as the erection gantry method and the deck crane method). As the solutions, incremental launching method is proposed. Then, as an example based on a certain suspension bridge in Western China, non-linear analysis is carried out in order to illuminate how to decide the important parameters in practical application. Some further problems are discussed at the end.

scholarly journals Comparison of the New Type Modular Panel for Green Roofs and Classical Construction of Green Roofs by Stormwater Management

2021 ◽  
Vol 1203 (2) ◽  
pp. 022118
Author(s):  
Martin Hejl ◽  
M. Mohapl ◽  
Lukas Bříza
Keyword(s):  
Stormwater Management ◽  
Laboratory Tests ◽  
Green Roofs ◽  
Construction Method ◽  
Measured Data ◽  
Urban Stormwater ◽  
Construction Methods ◽  
New Construction ◽  
New Type ◽  
Classical Construction

Abstract Proper stormwater management is one of the main problems cities today face. In order to understand how to properly manage urban stormwater it is first necessary to construct roofs with new construction methods. The first step for controlling urban stormwater is the construction of green roofs. We already know that the construction of green roofs improves water management in cities. But can we make it better? What will happen if we use the same layers for the green roofs but with a different construction method? This article wants to answer these questions. In this article the two green roofs, differing in the construction method, are compared and contrasted in terms of stormwater management. One of the green roofs was built traditionally, while the other has been built using a new type of modular panel. The article then compares their results during laboratory tests. In the conclusion you can read about measured data from tests and possible solutions and development of solutions to improve green roofs in the future.

Numerical Analysis of Construction Method in Shallow-Buried Large-Section Loess Tunnel

2014 ◽  
Vol 580-583 ◽  
pp. 997-1000 ◽  
Author(s):  
Zhi Jie Sun
Keyword(s):  
Numerical Simulation ◽  
Numerical Analysis ◽  
Ground Surface ◽  
Construction Method ◽  
Surrounding Rock ◽  
3D Numerical Simulation ◽  
Large Section ◽  
Research Results ◽  
Construction Methods ◽  
Ground Surface Settlement

To research the deformation regularity of large section loess tunnel in construction procession with different construction methods, 3D Numerical Simulation is applied and the large-section loess tunnel of highway is taken as an example. Comparing deformation regularity of surrounding rock in three types of construction method conditions, the research results show that:The CRD method takes precedence in the condition of the convergence of surrounding rock is large. The both sides heading method takes precedence in the condition of ground surface settlement is large.

ВЛИЯНИЕ ТВЕРДОФАЗНОЙ РЕКРИСТАЛЛИЗАЦИИ С ДВОЙНОЙ ИМПЛАНТАЦИЕЙ НА ПЛОТНОСТЬ СТРУКТУРНЫХ ДЕФЕКТОВ В УЛЬТРАТОНКИХ СЛОЯХ КРЕМНИЯ НА САПФИРЕ

2020 ◽  
Vol 96 (3s) ◽  
pp. 154-159
Author(s):  
Н.Н. Егоров ◽  
С.А. Голубков ◽  
С.Д. Федотов ◽  
В.Н. Стаценко ◽  
А.А. Романов ◽  
...  
Keyword(s):  
Dislocation Density ◽  
Solid Phase ◽  
Modern Method ◽  
Structural Defects ◽  
Structural Quality ◽  
Mos Transistors ◽  
Ultrathin Layers ◽  
Heteroepitaxial Layers ◽  
Xrd And Tem

Высокая плотность структурных дефектов является основной проблемой при изготовлении электроники на гетероструктурах «кремний на сапфире» (КНС). Современный метод получения ультратонких структур КНС с помощью твердофазной эпитаксиальной рекристаллизации позволяет значительно снизить дефектность в гетероэпитаксиальном слое КНС. В данной работе ультратонкие (100 нм) слои КНС были получены путем рекристаллизации и утонения субмикронных (300 нм) слоев кремния на сапфире, обладающих различным структурным качеством. Плотность структурных дефектов в слоях КНС оценивалась с помощью рентгеноструктурного анализа и просвечивающей электронной микроскопии. Кривые качания от дифракционного отражения Si(400), полученные в ω-геометрии, продемонстрировали максимальную ширину на полувысоте пика не более 0,19-0,20° для ультратонких слоев КНС толщиной 100 нм. Формирование структурно совершенного субмикронного слоя КНС 300 нм на этапе газофазной эпитаксии обеспечивает существенное уменьшение плотности дислокаций в ультратонком кремнии на сапфире до значений ~1 • 104 см-1. Тестовые n-канальные МОП-транзисторы на ультратонких структурах КНС характеризовались подвижностью носителей в канале 725 см2 Вс-1. The high density of structural defects is the main problem on the way to the production of electronics on silicon-on-sapphire (SOS) heteroepitaxial wafers. The modern method of obtaining ultrathin SOS wafers is solid-phase epitaxial recrystallization which can significantly reduce the density of defects in the SOS heteroepitaxial layers. In the current work, ultrathin (100 nm) SOS layers were obtained by recrystallization and thinning of submicron (300 nm) SOS layers, which have various structural quality. The density of structural defects in the layers was estimated by using XRD and TEM. Full width at half maximum of rocking curves (ω-geometry) was no more than 0.19-0.20° for 100 nm ultra-thin SOS layers. The structural quality of 300 nm submicron SOS layers, which were obtained by CVD, depends on dislocation density in 100 nm ultrathin layers. The dislocation density in ultrathin SOS layers was reduced by ~1 • 104 cm-1 due to the utilization of the submicron SOS with good crystal quality. Test n-channel MOS transistors based on ultra-thin SOS wafers were characterized by electron mobility in the channel 725 cm2 V-1 s-1.

The Physical Context of Child Development

2021 ◽  
Vol 30 (1) ◽  
pp. 41-48
Author(s):  
Gary W. Evans
Keyword(s):  
Child Development ◽  
Observational Studies ◽  
Physiological Stress ◽  
Personal Characteristics ◽  
Adverse Outcomes ◽  
Structural Quality ◽  
Physical Context ◽  
Physical Setting ◽  
Physical Features

Child development reflects interactions between personal characteristics and the physical and social environment. Psychology, however, lacks analysis of physical features that influence child development. In this article, I describe a preliminary taxonomy of physical-setting characteristics that can influence child development, focusing on environmental stressors such as noise, crowding, and chaos along with structural quality of housing, day care, and schools. Adverse outcomes associated with suboptimal physical settings during childhood include cognitive and socioemotional difficulties along with chronic physiological stress. Both direct effects on the child as well as indirect effects occurring via significant persons surrounding the child are described. Methodological limitations, particularly reliance on observational studies, are a weakness in the current literature, but increasingly more rigorously obtained findings yield converging evidence of the effects of physical settings on child development.

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