scholarly journals Stability Evaluation of TBM Pilot Tunnels to Rear Blasting Using the Protection Shield

2021 ◽  
Vol 11 (4) ◽  
pp. 1759
Author(s):  
Suk-Min Kong ◽  
Sang-Il Choi ◽  
Seung-Bo Shim ◽  
Hana Lee ◽  
Dong-Wook Oh ◽  
...  
Keyword(s):  
Tunnel Boring Machine ◽  
Separation Distance ◽  
Economic Feasibility ◽  
Environmental Damage ◽  
Construction Costs ◽  
Tunnel Excavation ◽  
Noise And Vibration ◽  
Construction Methods ◽  
Tunneling Method ◽  
Ground Conditions

Recent studies have increasingly investigated construction methods for tunnel excavation because of growing underground space development. Although the New Austrian tunneling method (NATM)—a representative tunnel excavation method—can be applied to various ground conditions, as well as having good constructability and economic feasibility, it suffers from problems such as vibration and noise. By contrast, excavation using a tunnel boring machine (TBM)—a representative mechanized construction method—affords advantages such as stable excavation, minimized ground and environmental damage, noise, and vibration. However, it cannot be applied easily to various ground conditions, and it suffers from problems such as high construction costs and delays owing to equipment defects. Therefore, the simultaneous pilot tunnel excavation using the TBM—which affords advantages such as constructability, economic feasibility, and minimized noise and vibration—and rear enlargement blasting using NATM was investigated in this study. A protection shield was installed to minimize accidents occurring from equipment defects (a disadvantage of TBM) and analyze the decrease in the effect of NATM blasting, which depends on the use of the protection shield and the separation distance through 3D numerical analysis.

scholarly journals Prediction of Subsidence during TBM Operation in Mixed-Face Ground Conditions from Realtime Monitoring Data

2021 ◽  
Vol 11 (24) ◽  
pp. 12130
Author(s):  
Hyun-Koo Lee ◽  
Myung-Kyu Song ◽  
Sean Seungwon Lee
Keyword(s):  
Construction Projects ◽  
Numerical Solutions ◽  
Short Term Memory ◽  
Tunnel Boring Machine ◽  
Related Factors ◽  
Construction Methods ◽  
Geological Conditions ◽  
Ground Conditions ◽  
Multiple Challenges ◽  
Operational Issues

The prediction of settlement during tunneling presents multiple challenges, as such settlement is governed by not only the local geology but also construction methods and practices, such as tunnel boring machine (TBM). To avoid undesirable settlement, engineers must predict the settlement under given conditions. The widely used methods are analytical solutions, empirical solutions, and numerical solutions. Analytical or empirical solutions, however, have limitations, which cannot incorporate the major causes of subsidence, such as unexpected geological conditions and TBM operational issues, among which cutterhead pressure and thrust force-related factors are the most influential. In settlement prediction, to utilize the machine data of TBM, two phases of long short-term memory (LSTM) models are devised. The first LSTM model is designed to capture the features affecting surface settlement. The second model is for the prediction of subsidence against the extracted features. One thing to note is that predicted subsidence is the evolution of settlement along TBM drive rather than its maximum value. The proposed deep-learning models are capable of predicting the subsidence of training and test sets with excellent accuracy, anticipating that it could be an effective tool for real-world tunneling and other underground construction projects.

Review on Construction Method of Subway Station

2011 ◽  
Vol 418-420 ◽  
pp. 2078-2081
Author(s):  
Wei Li
Keyword(s):  
Tunnel Boring Machine ◽  
Construction Method ◽  
Subway Station ◽  
Machine Method ◽  
Tunnel Boring ◽  
Construction Methods ◽  
Combination Methods ◽  
Tunneling Method ◽  
The World ◽  
Subway Stations

All the construction methods of subway stations are firstly reviewed in the world, which are cut and cover method, mine tunneling method, tunnel boring machine method and combination methods of them. Finally characteristics of various construction methods are analyzed in detail.

SURFACE SETTLEMENT INDUCED BY TUNNELING IN GREENFIELD CONDITION THROUGH PHYSICAL MODELLING

2015 ◽  
Vol 76 (2) ◽  
Author(s):  
Aminaton Marto ◽  
Mohamad Hafeezi Abdullah ◽  
Ahmad Mahir Makhtar ◽  
Houman Sohaei ◽  
Choy Soon Tan
Keyword(s):  
Relative Density ◽  
Physical Modelling ◽  
Diameter Ratio ◽  
Surface Settlement ◽  
Ground Movement ◽  
Outer Diameter ◽  
Tunnel Excavation ◽  
Tunneling Method ◽  
Relative Density Of Sand ◽  
Tunnel Shield

Geotechnical conditions such as tunnel dimensions, tunneling method and soil type are few factors influencing the ground movement or disturbance.  This paper presents the effect of tunnel cover to diameter ratio and relative density of sand on surface settlement induced by tunneling using physical modelling. The aluminum casing with outer diameter of 50 mm was used to model the tunnel shield. The size of the casing was 2 mm diameter larger than the tunnel lining. The tunnel excavation was done by pulling out the tunnel shield at constant speed with a mechanical pulley. The tested variables are cover to diameter ratio (1, 2 and 3) and relative density of sand (30%, 50% and 75%). The results demonstrated that the surface settlement decreased as the relative density increased. Also, as the relative density of sand increased, the overload factor at collapse increased. The surface settlement was at the highest when the cover to diameter ratio was 2.  It can be concluded that in greenfield condition, the relative density and cover to diameter ratio affect the surface settlement.

Route selection for natural gas pipelines in Ireland

1987 ◽  
Vol 4 (1) ◽  
pp. 467-474
Author(s):  
J. H. Redding
Keyword(s):  
Natural Gas ◽  
Rural Areas ◽  
Site Investigation ◽  
Geological Mapping ◽  
Route Selection ◽  
Construction Costs ◽  
Near Surface ◽  
Natural Gas Pipelines ◽  
Potential Difficulty ◽  
Ground Conditions

AbstractBy the end of 1986, over 400 km of high pressure (70 bar) natural gas pipeline will have been constructed in the Irish Republic, much of it laid in sparsely populated rural areas where topography, hydrology, near surface geology and ground conditions can significantly influence construction feasibility and cost. Identifying, quantifying and (where possible) avoiding areas of potential difficulty or hazard are aspects of route selection to which engineering geology can make an important contribution. This contribution is discussed in relation to the Cork-Dublin pipeline completed in 1982, and the Limerick, Waterford and Mallow lines due for completion this year. In particular, the application and merits of stereo aerial photographic interpretation, superficial geological mapping and field study are outlined, together with the use of more traditional methods of site investigation. Attention is focussed on indigenous engineering geological problems associated with shallow rock, limestone karst, peat bog and poorly drained alluvial and morainic soils. Data acquisition and presentation are discussed within the overall context of civil engineering contract preparation and administration. The usefulness of this approach, particularly for predicting and minimising construction costs, forestalling claims and generally facilitating on-site supervision, is emphasised.

New Techniques in Difficult Ground Tunneling

2000 ◽  
Vol 1740 (1) ◽  
pp. 175-181 ◽  
Author(s):  
Arturo Ressi di Cervia
Keyword(s):  
Traffic Flow ◽  
New Technique ◽  
Soil Conditions ◽  
Soft Ground ◽  
New Techniques ◽  
Tunnel Excavation ◽  
Ground Conditions ◽  
Full Face

The construction of tunnels under soft ground conditions has been solved by the use of special technologies and equipment. This equipment opens new possibilities for the enlargement of existing tunnels while maintaining traffic flow. The work can be done safely and economically even under the most difficult soil conditions. Two new tunneling techniques for the full-face excavation of galleries under difficult ground conditions and one new technique for cut-and-cover tunnel excavation are described.

The Comparison of Tunnel Engineering Construction Methods for Renhechang Tunnel Crossing Underneath Existing Tunnel on Lanzhou-Chongqing Railway

2013 ◽  
Vol 405-408 ◽  
pp. 1330-1333 ◽  
Author(s):  
Chuan Yi Sui ◽  
Xu Dong Zhou ◽  
Lin Hui Wang
Keyword(s):  
Field Measurement ◽  
Measurement Data ◽  
Tunnel Construction ◽  
Tunnel Engineering ◽  
Engineering Construction ◽  
Existing Structures ◽  
Construction Methods ◽  
Tunneling Method ◽  
Simulation Results ◽  
The Cross

Problems often exist in construction of transportation tunnels, such as the effect of new tunnels constructed close to existing structures. Solving this magnificent problem by carefully choosing tunnel construction methods will be beneficial to minimize effects on existing structures while ensuring the newly constructed tunnel is both time-consuming and economical. Three representative engineering methods-the benching tunneling method, the Center Diaphragm method and the Cross Diaphragm method-are compared in controlling the settlement of new tunnel vault and the deformation of the existing tunnel. Finally checking the simulation results by comparing with field measurement data.

Seismic‐while‐drilling by using tunnel boring machine noise

Geophysics ◽  
2002 ◽  
Vol 67 (6) ◽  
pp. 1798-1809 ◽  
Author(s):  
Lorenzo Petronio ◽  
Flavio Poletto
Keyword(s):  
Large Diameter ◽  
Tunnel Boring Machine ◽  
High Amplitude ◽  
Direct Access ◽  
S Wave ◽  
Tunnel Excavation ◽  
Tunnel Boring ◽  
Cutting Head ◽  
Geothermal Wells ◽  
Radial Dimension

The tunnel boring machine (TBM) is used extensively to mechanically excavate tunnels. To optimize the mechanical drilling and work safely, an estimate of the geology to be drilled is necessary. We consider using the elastic waves produced by the TBM cutting wheel to obtain seismic‐while‐drilling (SWD) information for predicting the geology ahead of the drilling front. This method uses accelerometers mounted on the TBM together with geophones located along and outside the tunnel, similar to the technique successfully used to drill oil and geothermal wells. Study of noise and the resolution of the signal produced by the large‐diameter cutting head shows that nonstationary noise separation can be achieved by locating sensors at the front and rear ends of the tunnel. The (higher) resolution in front of the TBM is limited by pilot delays, while the (lower) lateral resolution is limited by the radial dimension of the TBM. Analysis of seismic data acquired in a field test shows that P‐ and S‐wave arrivals have a wide frequency band and high amplitude in seismic traces measured 700 m away from the drilling front. In comparison with SWD applications in wells, tunnel SWD technology has the advantage of allowing direct access to the tunnel front, which makes it easy to connect the TBM reference sensors for while‐drilling monitoring. This method can be successfully applied without interfering with drilling activity to monitor tunnel excavation continuously, reduce risks, and optimize drilling.

scholarly journals Effects of different processes of tunneling on displacements soil using 3D Finite Element Method

2021 ◽  
Vol 16 (2) ◽  
pp. 203-217
Author(s):  
Nawel Bousbia
Keyword(s):  
Three Dimensional ◽  
Urban Site ◽  
Tunnel Excavation ◽  
Excavation Process ◽  
Tunneling Method ◽  
The Stability ◽  
Full Face ◽  
Ground Stability ◽  
3D Finite Element Method ◽  
Underground Constructions

Abstract The excavation process of tunnels induces stresses and deformation in the surrounding soil. The method of excavation is one of the major problems related to the safety of the operators and the ground stability during the construction of underground works. So, it is necessary to choose an ideal method to minimize the displacements and stresses induced by tunneling. The main aim of this study is to simulate numerically the effect of different processes of tunneling on ground displacements, the settlements at surface soil and the internal efforts induced in the lining tunnel; in order to select the best process of excavation, which gives us a less effects on displacements generated by tunneling, thus, ensuring the stability and the solidity of the underground constructions. In addition, this study allows us to control and to predict the diverse movements generated by tunneling (displacements, settlements, efforts internes) exclusively for the shallow tunnel nearby to the underground constructions in the urban site. This modeling will be done by employing five different processes for tunnel excavation using the NATM (New Austrian Tunneling Method) method. The first process, the modeling of the excavation tunnel, is done almost in the same way as in reality; the partial face excavation, with seven slices, made by the excavation. The second process, by partial face excavation, is divided into eleven slices, next, we used the partial face excavation by nine slices, and then in thirteen slices. Finally, the dig is made by full-face excavation. The paper contributes to the prediction of the response of the soil environment to tunnel excavation using the NATM method and to minimize the diverse movements generated by tunneling. The appropriately chosen methodology confirms that displacements and subsidence are strongly influenced by the tunneling method. The three-dimensional Finite Elements Method using Plaxis3D program has been applied in the numerical simulation. The study resulted in the recommendation of a process that minimizes the effect of excavation on subsidence and ground displacement for a particular Setiha tunnel.

Sustainable Techniques for Public School in Florida: Application of the Sustainable Urban Drainage System (SUDS)

2015 ◽  
Author(s):  
Sahar Abdulraheem ◽  
Nawari O. Nawari
Keyword(s):  
Public Schools ◽  
Drainage System ◽  
Water Flooding ◽  
Storm Water ◽  
Water Runoff ◽  
Urban Drainage ◽  
Construction Costs ◽  
Urban Drainage System ◽  
Construction Methods ◽  
Flood Damages

Floods are among the most common natural hazards in Florida. They are threatening the safety and economic welfare of Floridians. Every year Florida spends millions of dollar to mitigate direct flood damages. Amongst the effective solutions to these flood damages is the control of urban drainage in school buildings and nearby grounds to conserve and preserve natural resources and to promote sustainable thinking. This paper discusses how public schools in Florida can benefit from sustainable techniques by applying the sustainable urban drainage system (SUDS) to school designs. The article also illustrates how Florida can use school sites as double functions to provide an active educational environment and to manage storm water runoff at the same time. Construction costs estimation for sustainable techniques is calculated based on data available for the year 2011 and compared with the conventional construction methods for schools. The result indicates a high initial cost that can easily be offset by considering the cost of conventional drainage structure, conserved storm water, flooding impact, storm water sewage disposal, and other measures.

scholarly journals Water Treatment Emergency: Cost Evaluation Tools

2019 ◽  
Vol 11 (9) ◽  
pp. 2609 ◽  
Author(s):  
Giovanna Acampa ◽  
Maria Gabriella Giustra ◽  
Claudia Mariaserena Parisi
Keyword(s):  
Wastewater Treatment ◽  
Wastewater Treatment Plants ◽  
Treatment Plant ◽  
Economic Feasibility ◽  
Cost Evaluation ◽  
The European Union ◽  
Construction Costs ◽  
Feasibility Assessment ◽  
Eu Member States ◽  
Electromechanical Equipment

The European Union is committed to enforce limitations to water pollution through specific directives (UWWTD 91/271/EEC). The delay of some EU member states in transposing these directives has had an impact on the quality of the wastewater treatment system. Therefore, it is necessary to intervene with adjustment procedures and construction of new plants. The aim of the study is to carry out an economic feasibility assessment for the construction costs of an urban wastewater treatment plant of medium-low capacity (<50,000 Population Equivalent or pe) according to a simplified process diagram, and help in the planning of new investments. We propose a methodology based on cost functions according to two different procedures: synthetic estimate of the costs for civil works and a multiple linear regression for the cost of the electromechanical equipment. These functions show a correlation between the construction costs and the population equivalent and enable us to understand it. The results show greater economic benefit in increasing wastewater treatment plants sizes serving a population equivalent of 5000 pe to 10,000 pe, while further increases are less beneficial.

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