1.0.1 This code is formulated with a view to adapting the demand of urban rail transit construction and development, unifying the requirements for survey technique of urban rail transit engineering, and complying with the principle of advanced technology, economy and rationality, reliable quality and safety and usability.
1.0.2 This code is applicable to engineering survey for newly-built urban rail transit and old line renovation and during operation period.
1.0.3 The rail transit engineering control survey in the same city shall meet the following requirements:
1 The horizontal and elevation system shall be consistent with that of the located city;
2 Before engineering construction, dedicated horizontal and elevation construction control network shall be established on the basis of urban first order or second order horizontal and elevation control network, and the differences from the coordinates of existing urban control network coincidence point and from the elevation shall not be greater than 50mm and 20mm respectively;
3 Before construction, the built horizontal and elevation control network shall be re-surveyed, and tested in construction.
1.0.4 The interurban rail transit engineering control survey shall not only meet Clauses 2 and 3 of Article 1.0.3 in this code, but also adopt uniform coordinates and elevation system; where interurban coordinates and elevation system are inconsistent, they shall be subjected to corresponding conversion.
1.0.5 The line engineering control survey shall adopt connecting traverse (network) and connecting elevation route type. Under special circumstances, when open traverse and spur levelling line are adopted, inspection and check measures must be established.
1.0.6 Before tunnel penetration, connection survey, underground horizontal control survey and underground elevation control survey shall be carried out for three times independently along with the engineering progress; after the tolerance is met, the average value of each survey shall be used to guide the tunnel penetration.
1.0.7 The mean square error of transverse holing through survey of undermined and open cut tunnel as well as overhead structure is ±50mm and that of elevation holing through survey is ±25mm.
1.0.8 The line construction, adjacent main buildings and structures, pipelines, etc. shall be subjected to deformation and settlement monitoring within construction period and within certain time during operation period, and emergency deformation and settlement monitoring scheme shall be established.
1.0.9 The acceptance survey shall be carried out according to the requirements of engineering completion acceptance, and the work content and survey technique requirements shall meet the relevant requirements of the current national survey code, engineering acceptance code and engineering data management.
1.0.10 The survey instruments and tools shall be verified periodically according to the relevant laws and regulations of the nation. During operation, the influence of operating environment on instruments shall be avoided.
1.0.11 The urban rail transit engineering survey shall not only comply with this code, but also the requirements of the relevant national current standards.
