Heavy excavation anti-corrosion foundation for ultrahigh voltage transmission line in salty soil region and preparation method

Abstract

The invention provides a heavy excavation anti-corrosion foundation for an ultrahigh voltage transmission line in a salty soil region and a preparation method. The method includes the steps: preparing a concrete cushion; preparing a concrete foundation body on the concrete cushion; brushing at least two layers of HCPE (high chlorinated polyethylene) anti-corrosion primer and at least three layers of HCPE anti-corrosion finish paint on the top of the concrete cushion and the surface of the foundation body. The fall of the concrete foundation body within the 2m range of the surface longitudinal and latitudinal evenness of the concrete foundation body, the thickness of each paint film is 40-50 micrometers, and specific substrate temperature, coating temperature, construction environment temperature and relative humidity need to be controlled. The foundation prepared according to the method has fine durability and corrosion resistance, and is applicable to ultrahigh voltage transmission line tower construction in the salty soil region.

Description

technical field [0001] The invention relates to the technical field of foundations for transmission lines, in particular to a large-excavation anti-corrosion foundation for transmission line poles and towers suitable for saline soil areas and a preparation method thereof. The durability of the prepared foundation is greatly improved compared with ordinary foundations and can be used Make the foundation work properly within the designed service life. Background technique [0002] The safety and reliability of transmission line tower foundations are crucial to the safe operation of transmission lines. In saline soil areas, the foundation concrete of transmission line towers is prone to corrosion, cracks, gradual peeling and loss of bearing capacity. [0003] Saline soil is a soil with high salt content, which is a general term for saline soil, alkaline soil and various salinized and alkalized soils. It has the characteristics of corrosion, dissolution and salt swelling. In s...

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Problems solved by technology

The comprehensive treatment measures in Table 1 do not specify the strength grade of concrete to be used under different corrosion levels, and it is not easy for designers to refer to the value when designing the foundation;

[0009] 2) Cement itself contains a certain amount of salt, and the salt content of different types of cement is also different. Cement that exceeds a certain salt content is corrosive to steel bars. Table 1 has relatively broad regulations on cement types (strong corrosion does not specify cement species), not clear;

[0010] In addition, according to Article 5.5.4 of the "Building Code for Saline Soil Areas", medium and high sulfate-resistant cements should be used as cement varieties for concrete in moderately strong corrosion areas, while according to "Sulfate-resistant Portland Cement" (GB748- 2005), the content of calcium oxide in medium-resistant sulfate cement and high-resistant sulfate cement is low (low alkalinity), which makes the concrete poor in compactness, although it can resist SO 4 2- erosion, but in Cl 1- Under corrosive conditions, steel bars will corrode, so it is only suitable for projects in a single sulfate corrosion environment, not for projects in both sulfate and chloride corrosion environments; Standards such as JTJ275 do not recommend the use of medium-resistant sulfate cement and high-resistant sulfate cement. GB50046-2008 also indicates that when the medium contains ionic SO 4 2- In addition to containing other corrosive ions, the corrosion resistance of sulfate-resistant Portland cement should be determined through experiments in addition to the actual use experience; in addition, the early strength of sulfate-resistant cement is low, and it is not suitable for prefabricated components;

[0011] 3) In Table 1, the treatment measures under strong corrosion limit the minimum cement dosage, which is difficult to achieve in the actual construction of concrete preparation operations;

[0012] 4) The effective service life of asphalt paint is short, and it is not as dense as resin when it is bonded to concrete;

[0013] 5) The scope of coating for external protection is not clear, and the coating thickness is not clear;

[0014] 6) The bottom plate of the large-scale excavation foundation is subject to complex forces and is prone to cracks, so it is more susceptible to erosion, and a cushion must be set. The comprehensive treatment measures in Table 1 are for large-scale excavation foundations. None stipulated

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