Tunnel definition:
The tunnel is a horizontal or almost horizontal underground corridor connected to the open air from both sides.
Tunneling steps
A) Preparing the tunnel plan
B) Route mapping and engineering research
C) Digging the tunnel
D) Tunnel temporary storage
Tunnel classification:
In general, tunnels can be divided into three categories of transport tunnels, industrial tunnels and mineral tunnels.
Transportation tunnels: These tunnels are designed for the purpose of commuting and transporting materials and are divided into the following groups:
A) Railway tunnels
B) tunnel roads
(C) pavement tunnels
D) Navigation tunnels
E) Metro tunnels
Industrial tunnels:
These tunnels are constructed to transport material and facilities and include the following tunnels:
(A) Waterway tunnels
B) Water transfer tunnels
(C) Public use tunnels and shelters
D) sewage tunnels
E) industrial designs tunnels
And) military storks
D) Atomic Waste Tunnels
Tunneling
Mineral tunnels:
These tunnels, which are excavated in order to construct a network of mines, include submerged tunnels:
A. Open mine tunnels
B) exploratory tunnels
(C) Extractive tunnels (such as corridors, galleries)
D) service tunnels
E) drainage tunnels
Transport tunnels are designed as permanent structures for long-term use, and their maintenance systems are fundamentally different from mine tunnels.
Among other differences are mining and transportation tunnels, their dimensions. Mineral tunnels have limited dimensions, while transport tunnels have a much larger dimension.
Before excavating and constructing the tunnel, you should study the area and select the most appropriate tunnel route, and then study the route. It is clear that these studies are time-consuming, but without doing so, there may be some major bottlenecks during the construction of the tunnel.
In general, routing studies can be categorized as follows:
A. Collection of district information
B) Review aerial photos and topographic maps of the area
(C) Surface geological studies
(D) Geophysical studies
L) drill exploratory boreholes
E) Hydrological studies
D) Digging exploratory galleries
And) tests on the spot
E) laboratory tests
From the point of view of engineering, the soil or rock that passes through the tunnel is in fact a kind of building material and therefore, in order to be able to choose the appropriate drilling and maintenance, it is necessary to first identify the engineering features of the genes well. .
Given the fact that in fact the ground floor constitutes a building material for underground space, not temporary or permanent coatings when designing tunnels, consider the following points:
A) A detailed study of the geological and geotechnical location of the site
B) implementing more and more of its design and implementation with the natural conditions of the earth
C) Minimization of the natural state of the earth
D) permanent recording of the movements of the Earth around the created space
Before any field investigation, you must first collect the information. To do this, you should get information about potential organizations by visiting organizations and institutions that may have been operating in the region. This information includes:
A) Topographic map of the area, usually provided by the country mapping organization or geographic organization of the army
B) Geological map of the region, to be supplied by the geological organization of the country
C) Aerial photos of the region to be submitted to the Geographical Organization of the Army
D) refer to databases for possible prospective investigations of the area
Tunnel Construction Assessment: According to studies on tunnel construction, the geotechnical range can be assessed. Basically, depending on the reaction of the earth to the creation of a tunnel (or any other underground space), it divides it into two general groups with appropriate and inappropriate conditions. If the ground conditions are appropriate, there will be no problem in tunneling the tunnel, while in case of inappropriate land, the tunnel may be in danger or cause an unusual delay, delay, and an extraordinary increase in costs.
In such a situation, before landing the tunnel, the land should be restored. The main determinants of ground conditions are:
A. Specifications of stone
B) soil
C) Groundwater
D) Other factors
Forecast earth leakage:
Due to the construction of the tunnel, the state of the tensions affecting the ground changes, which leads to deformation. If no action is taken to control these deformations, the tunnel can leak and its impact reaches the ground and eventually cause leakage of buildings and installations located above the tunnel. One of the other factors that is effective in land leakage is the drainage of the underground water in the area through the tunnel, resulting in a lower level of watertightness.
Considering the importance of the earth leakage phenomenon, it is necessary to select methods for digging and storing tunnels to minimize leakage.
In some cases, designing and maintaining a proper maintenance system prevents effective land leakage, and sometimes it is necessary to improve or strengthen the land. The degree of leakage depends on the geological conditions, the dimensions of the tunnel and the method of drilling and maintenance.
The leakage phenomenon is usually more important than tunneling in earthy soils than rocky terrain, but in some cases inadequate drilling and maintenance of tunnels in heavy lands has also led to the phenomenon of sedimentation.
Figure and dimensions of the tunnel section:
Choosing the shape and dimensions of the tunnel section is the function of the purpose of constructing a tunnel, the tunnel drilling system, the loading method and its permanent maintenance method. In cases where the use of different shapes is possible, one has to choose a form that minimizes the total cost of tunnel construction.
Metro Tunnels:
The dimensions of the metro tunnels also depend on the type of trains and their speed.
Tunneling
Tunnel stretches:
Minimum radius of curvature