When the train passes through the high-speed railway tunnel, many people will have a question: the high-speed railway tunnel is so long, it will dig out a lot of earth and rocks, but there is no pile of earth in front of the tunnel, and it can not be seen out of the tunnel, so where are the excavated earth?
Let's make a brief introduction.
During the construction of high-speed railway tunnel, there is a part called earthwork allocation. Generally, the balance between excavation and filling in the design drawings will be balanced as far as possible, such as filling the roadbed with earthwork excavated from the tunnel. Some of them have good geological conditions, and the excavated stones can be completely reused. Others have built a gravel yard near the tunnel for the supply of Engineering gravel, mixing concrete and so on. Even the surplus can be sold to the outside world, which reduces the cost. There are many redundant and useless earthworks, which will requisition a waste yard nearby, or fill in low-lying mountain canyons, which will cause greater damage to the local environment, so later on, it will protect and re-cultivate, minimizing the impact.
In addition to the construction of sidewalks or earthwork allocation, the remaining earthwork will be dumped to the designated abandonment site. Since the collapse accident of Shenzhen abandonment site, the water conservancy administrative department has put forward strict conditions for the approval of abandonment site. The selection and approval of each abandonment site requires one-to-one review by the water conservancy department. If the designed abandonment site can not be used after the project starts, a change can be proposed. The selection of new abandonment site also requires on-site examination and approval by the water conservancy department. It is illegal to discard dregs without the permission of the water administrative department. The design of the dregs yard, from the dregs retaining wall, the dregs dam to the greening vegetation, should be carried out simultaneously with the design drawings and the main project. The total amount of earthwork used should be written in the design drawings, and the construction should be carried out all the time. Finally, it must pass the acceptance of water and soil conservation.
High-speed railway tunnels should mainly appear in mountainous areas, which are the focus of ecological protection, and environmental protection measures are very important. And in the mountain tunnel construction, shield or blasting out of the main rock, in order to restore the ecological environment, these rocks and soil will certainly take timely measures. For example, timely shipment, filling roadbed, for meeting the requirements of rock processing can be used as building materials.Tunnels are usually excavated between mountains, with gullies nearby. Usually, it takes money and time to build platform by filling the hill and gully, and the earth and rock excavated by opening the tunnel can meet the needs of filling and roadbed. It can also be used as a platform for filling ditches, making land, planting trees and planting plants nearby.