1.0.1 This code is formulated with a view of unifying technical requirements of railway tunnel construction, guaranteeing the construction quality, and making the tunnel construction comply with requirements of safety and usability, state-of-the-art technology as well as economic feasibility.
1.0.2 This code is applicable to construction and acceptance of newly built and renovated full-gauge railway tunnel works.
1.0.3 Tunnel works must be constructed according to the approved design documents, and shall be implemented according to current modification management method if the modification is necessary.
1.0.4 When railway tunnel is constructed through drilling and blasting, the shotcrete-bolt construction method should be adopted in priority and the dynamic management should be implemented.
1.0.5 Length grade division of railway tunnel shall comply with the following provisions:
1 Those less than 500m in length are short-length tunnels;
2 Those more than 500m and less than 3000m in length are medium-length tunnels;
3 Those more than 3000m and less than 10000m in length are long-length tunnels;
4 Those more than 10000m in length are over-length tunnels.
1.0.6 Division of excavated section grade of railway tunnel shall comply with the following provisions:
1 Cross-section areas less than 10m2 are small sections;
2 Cross-section areas more than 10m2 and less than 50 m2 are medium sections;
3 Cross-section areas more than 50m2 and less than 100m2 are large sections;
4 Cross-section areas more than 100m2 are oversize sections.
1.0.7 According to the general construction plan of railway construction, the following works shall be well implemented on the base of the specific conditions of the construction organization for the tunnel construction:
1 Against the in-site characteristics and on the basis of the survey and design documents, the proper construction method shall be selected;
2 The construction preparation works and tunnel opening ancillary works shall be well implememted so as to create favourable conditions for tunnel construction;
3 Rational arrangement for working procedure and operation of key work program shall be made, and stable production shall be organized;
4 According to construction conditions and requirement of construction period, model selection and matching for construction machinery shall be implemented, integrative capability of the equipment shall be fully used, and the level of mechanized construction shall be gradually improved;
5 conditions for ventilation, illumination and dustproof shall be improved. It is also required to lower the temperature and prevent harmful gas so as to keep the operators in good condition;
6 Relevant safety measures shall be formulated, and the safety code shall be strictly observed so as to ensure the construction safety;
7 Explanation for all the technologies and in-site test shall be well implemented, all operation specifications shall be strictly observed so as to ensure the construction quality;
8 It is alsi required to positively deploy new technologies, new process, new materials and new facilities; continuously improve construction technology and perfect in-site management, improve the level of construction technology; save energy and reduce material consumption, as well as improve integrated economic benefit of tunnel construction.
1.0.8 Tunnel construction
”’ shall comply with the specified survey accuracy, adopt relevant measurement, establish recheck system, and guarantee that midline, level correction, excavated section, lining thickness and clear opening size comply with specifications.
1.0.9 When the tunnel is completed, it is required to compile specific and overall summary for construction technology according to construction characteristics, as well as submit complete documents. During the construction, it is required to collect raw data and documents at any moment and get done with concerned construction note.
1.0.10 Tunnel construction shall protect the environment against pollution, carry out civilized construction. Relevant measures must be adopted when influence to environment can't be avoided.
1.0.11 For construction of railway tunnel project, not only the requirements stipulated in this code, but also those in the current relevant mandatory standards of the nation shall be complied with.
