Old road reconstruction and expansion, culvert construction

Abstract With the continuous development of my country's economy, the throughput of my country's highways is also increasing. Since my country's expressways cannot meet current traffic needs, in order to alleviate traffic pressure, expressways must be reconstructed and expanded. With the increase in the number of highway reconstruction and expansion projects, the country has begun to pay more attention to them and continuously improve their technical level to enhance the quality of the reconstruction and expansion projects. Especially in the culvert design during the reconstruction and expansion process, the technical requirements for them have become more stringent. Strict, so it is of great significance to study and analyze the culvert design in highway reconstruction and expansion.

Keywords expressway; reconstruction and expansion; culvert design

CLC number: U449.1 Document identification code: A Article number: 1006-8465(2015)12-0121- 01

Highway construction is a basic project in our country. The reconstruction and expansion of highways is a very important task. It not only improves traffic pressure, but also has a great impact on our country’s economy. Development also helps. Reconstruction and expansion of highways are the main ways to achieve high traffic capacity, reduce operating costs, and improve transportation conditions. At present, the design scheme of highway bridges and culverts in our country is not mature enough, so the research on its design scheme is particularly important. 1 Design principles for culverts in highway expansion? 1.1 Standards for reconstruction of old culverts During the process of highway reconstruction and expansion, the specific conditions of the old culverts must be inspected and judged, combined with the design load that needs to be reconstructed and the filling conditions at the top of the culvert. Analyze and understand the height, culvert clearance and geological conditions of the area [1]

. Determine whether the old culvert can still meet the usage requirements. Those culverts with insufficient overall load capacity, serious settlement of the culvert foundation, or other parts that cannot meet the use requirements will not be rebuilt and must be abolished. 1.2 Lengthening of the old culvert When extending the old culvert, the extended part should have the same structure as the old culvert and the same cross-section. The opening of the old culvert should be removed, and the gap between the old culvert and the new culvert should be removed. Set settlement joints at the seams. It is necessary to clear the siltation at the bottom of the usable section of the old culvert, check the condition of the old culvert, and repair some damaged areas of the old culvert. Where the local load capacity of the old culvert is insufficient, reinforcement must be carried out to meet the quality of the highway expansion. 2 Design plan for culverts in expressway expansion 2.1 Methods for lengthening old culverts When lengthening the culverts on the Du Gong'ansu Highway, the soil shoulders on both sides of the original extended part of the road section should be excavated and connected. Protect the long side slope, remove 30cm of topsoil, and set soil steps on the side of the old road. After the splayed wall is dismantled, it must be supported in time to prevent the sand and soil above from escaping and causing the roadbed to collapse.

Steel sheet piles must be driven before excavation of the roadbed, in order to affect the old roadbed during foundation excavation and ensure that the original highway structure remains intact during the expansion construction process. Can be used normally[2]