Comparison of construction methods for shallow burial tunnel with soft rock and large span

Many problems are encountered in the construction of bifurcated tunnels due the abrupt change in section, small clear distance, and large section. Progress in the direction of tunnel construction is limited by the large-span section; therefore, a special method of construction that involves constructing a guiding tunnel first followed by reverse excavation was adopted to construct the large-span bifurcation section of the Liantang tunnel of Shenzhen Eastern Transit Expressway in China. The stability criterion of the surrounding rock of the middle wall in the section of multiple arch and small clear distance is studied by theoretical analysis, and the internal stress and corresponding ultimate strength of the middle wall under different buried depths and widths of the middle wall are calculated by the stability criterion. In this study, 3D finite-difference software was used to simulate the excavation process under forward and reverse excavation conditions. The results show that the displacement field and internal force field distribution are similar for both excavation methods, and the tunneling first and reverse excavation construction method is safe and reliable.

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Study on Predictin of Surface Subsidence of an Exremely Shallow Large-Span Double-Arch Tunnel

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.396-398.2245 ◽

2011 ◽

Vol 396-398 ◽

pp. 2245-2248

Author(s):

Xin Zhi Li ◽

Shu Cai Li ◽

Shu Chen Li ◽

Xian Da Feng ◽

Chao Yuan ◽

...

Keyword(s):

Numerical Simulation ◽

Model Test ◽

Surface Subsidence ◽

Tunnel Construction ◽

Geomechanical Model ◽

Large Span ◽

Geomechanical Model Test ◽

Construction Methods ◽

Surface Subsidence Control ◽

Great Wall

The Qi-Great Wall tunnel which crossed the Qi -Great Wall ruins was a large span double-arch tunnel with two-way and six-lane and the maximum depth was less than 5 meters, in order to protect the safety of thr surface ruins in the tunnel construction progress, surface subsidence control was particularly important. Through comprehensive geomechanical model test and numerical simulation , the surface subsidence wich generated in the process of construction according to construction methods of excavation and support was studied, the distribution of surface subsidence got through two methods was fitted well,and research results could provide guidance for the construction.

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Study on Identification of Construction Method for Ultra-Large-Span Tunnel

Advances in Civil Engineering ◽

10.1155/2020/6625940 ◽

2020 ◽

Vol 2020 ◽

pp. 1-11

Author(s):

Xu Chongbang ◽

Qin Youlin

Keyword(s):

Rock Strength ◽

Construction Method ◽

Surrounding Rock ◽

Orthogonal Test ◽

Tunnel Construction ◽

Test Model ◽

Large Span ◽

Construction Methods ◽

The Stability

Although the determination of tunnel construction methods is extremely critical for the construction of ultra-large-span tunnels, the determination of construction methods is still at a qualitative level, which relies on the engineering experience of on-site technicians and lacks rigorous and systematic theoretical basis and technical standards. By means of orthogonal test method, the proper construction method was established for the deep-buried ultra-large-span tunnel where the tunnel excavation span, tunnel surrounding rock strength, and rock integrity coefficient were set as the main control factors. The stability of tunnel surrounding rock under various test conditions was quantified according to the plastic zone properties calculated by the three-factor and five-level orthogonal test model. Meanwhile, the macro form and quantitative method of test combinations under different levels of various factors were proposed to obtain the influence of each factor on the stability of tunnel surrounding rock, and thus the functional relations between various factors and tunnel stability were obtained. On this basis, the identification and the criterion of the ultra-large-span tunnel construction method were established, which can quantitatively reflect the contribution of excavation span of the tunnel, the number of lateral drifts in cross section, surrounding rock strength, and rock integrity coefficient to surrounding rock stability of the tunnel. The construction method calculation results of the Malin tunnel, a practical underground project, are obtained according to the orthogonal test model calculation. Based on the method, Malin tunnel can be constructed safely and efficiently. The research results could provide the theoretical basis for the identification and selection of construction method for ultra-large-span tunnel.

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Deformation mechanism and excavation process of large span intersection within deep soft rock roadway

Mining Science and Technology (China) ◽

10.1016/s1674-5264(09)60156-3 ◽

2010 ◽

Vol 20 (1) ◽

pp. 28-34 ◽

Cited By ~ 3

Author(s):

Guofeng LI ◽

Manchao HE ◽

Guofeng ZHANG ◽

Zhigang TAO

Keyword(s):

Deformation Mechanism ◽

Soft Rock ◽

Large Span ◽

Excavation Process ◽

Soft Rock Roadway ◽

Rock Roadway

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Two-Way Pre-Stressing Technology Applied to Large-Scale Aqueduct of Tanglai Channel through Beita Lake

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.243-249.4511 ◽

2011 ◽

Vol 243-249 ◽

pp. 4511-4515

Author(s):

Zhuo Li ◽

Si Hong Liu ◽

Xu Dong Yang ◽

Shan Mai ◽

You Ting Feng

Keyword(s):

Large Scale ◽

Design Code ◽

Construction Period ◽

Large Span ◽

Construction Methods ◽

Stress And Deformation ◽

Complicated Conditions ◽

Design And Construction

In view of particularity of the Tanglai channels aqueduct，which crosses Beita Lake, the conventional construction methods and technologies fail to work, so the new two-way pre-stressing technology is employed. After the sidewalls in large span structures of aqueduct were pre-fabricated and hoisted，the secondary floor was poured in design and construction plan. The results show that the comprehensive function of aqueduct is implemented in complicated conditions，such as short construction period，larger span of structures，navigation under aqueduct，pre-fabrication and hoisting of larger sidewalls. The stress and deformation of aqueduct meet the requirements of design code.

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SUSPENSION LARGE SPAN ROOFS STRUCTURES IN RUSSIA

International Journal for Computational Civil and Structural Engineering ◽

10.22337/2587-9618-2021-17-2-34-42 ◽

2021 ◽

Vol 17 (2) ◽

pp. 34-42

Author(s):

Pavel Eremeev ◽

Ivan Vedyakov ◽

Andrey Zvezdov

Keyword(s):

Thin Sheet ◽

Social Consequences ◽

Sports Facilities ◽

Large Span ◽

Advantages And Disadvantages ◽

Construction Methods ◽

Thin Sheet Metal ◽

Bicycle Wheel ◽

Suspended Roof ◽

Design And Construction

Сonsidered are large-span structures with suspended roof structures with a span of up to 200 m, erected in Russia over the past 40 years. Among them, there are differen types of structures for covering sports facilities: cablestayed systems, structures of the "bicycle wheel" type, combined systems, thin-sheet metal hanging shells, etc. The main technical characteristics of structures, principles of operation of structures, their advantages and disadvantages are given. The development of technologies in recent decades has determined the emergence of new forms, materials, design and construction methods. Unique large-span structures have an increased level of responsibility; their collapse can lead to severe economic and social consequences. In this regard, it is relevant to analyze the experience in the design and construction of large-span suspended structures.

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The Construction Process Simulation of a Large-Span Rhombic Space Truss Using FEM Analysis

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.368-373.1101 ◽

2011 ◽

Vol 368-373 ◽

pp. 1101-1104

Author(s):

Xu Yan ◽

Tie Ying Li ◽

Yun Jing Nie

Keyword(s):

Fem Analysis ◽

Construction Process ◽

Large Span ◽

Construction Design ◽

Construction Methods ◽

The North ◽

Space Truss ◽

Design Theories ◽

The Stability ◽

Space Trusses

With the developments of the design theories and the researches, the quantity and the technology of space truss systems in our country have reached the international leading level. In the meantime, the construction methods need to achieve even higher standard. In the article, the rhombic space truss roof of the north station building of Suzhou is selected as the research object. Each step of the sliding and unloading construction is simulated by FEM. The stability and rigidity of the truss are checked in detail. It gives an representative exsample for complicated construction design of large-span space trusses.

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