1 General
1.0.1 These regulations are formulated to unify the technical requirements for geological investigation of highway cross-harbour passage projects and improve the quality of engineering geological investigation.
1.0.2 These regulations are applicable to the geological investigation of bridges, tunnels, artificial islands, temporary works and material yards of highway cross-harbour passages.
1.0.3 The geological survey shall be carried out in stages in accordance with the basic procedures of highway construction.
1.0.4 Geological investigation of highway cross-harbour passage projects shall actively apply new methods, equipment, techniques and technologies that are mature and can be applied.
1.0.5 In addition to the provisions of these regulations, the geological survey of highway cross-harbour channel projects shall also conform to the provisions of the relevant national and industry standards in force.
2 Terminology and symbols
2.1 Terminology
3 Basic provisions
3.1 General provisions
3.1.1 Engineering geological survey for highway crossings shall be divided into pre-feasibility stage engineering geological survey (referred to as pre-feasibility survey), engineering geological survey at engineering feasibility stage (referred to as engineering survey), engineering geological survey at preliminary design stage (referred to as preliminary survey or initial survey), engineering geological survey at construction drawing design stage (referred to as detailed survey or detailed survey), engineering geological survey at construction stage (referred to as construction survey) in five sections.
4 Pre-survey and engineering survey
4.1 Preliminary survey
4.1.1 The pre-feasibility survey shall understand the engineering geological conditions and the main engineering geological problems in the area where the highway cross-harbour passage project is located, and provide engineering geological information for the preparation of the pre-feasibility study.
4.1.2 The pre-feasibility survey shall be based on data collection, remote sensing engineering geological interpretation and engineering geological mapping, combined with physical prospecting, drilling, sampling and testing, in-situ testing and other methods to study the engineering geological conditions of the highway cross-harbour passage.
5 Preliminary survey
5.1 General provisions
5.1.1 The preliminary survey shall basically identify the engineering geological conditions of the construction sites such as bridges, (19) roads, artificial islands, temporary resistance works and material yards of the highway cross-harbour passage, and provide engineering geological information for the engineering scheme selection and preliminary design document preparation.
5.1.2 The preliminary survey shall, on the basis of making full use of the engineering feasibility survey information, investigate the engineering geological conditions of the route and all kinds of structures according to the engineering geological conditions and hydrogeological conditions along the route, combined with the metric scheme of bridges, tunnels, artificial islands and other structures, and adopt a comprehensive survey method.
6 Detailed survey
6.1 - General provisions
6.1.1 The detailed survey shall be based on the engineering scheme determined by the preliminary design, and the engineering geological conditions of the site where the proposed structures are located shall be specified in detail in a targeted manner to provide engineering geological information for the preparation of the construction drawings).
6.1.2 The detailed survey shall make full use of the geological information obtained from the preliminary survey, and adopt a comprehensive survey method mainly based on the use of soundings, in-situ tests and indoor tests, supplemented by physical means.
6.2 Bridges
6.2.1 Bridge detailed survey should be based on the geological conditions re-fracture laxity, pre-survey salty dye and bridge type, bridge span, foundation type, etc. to determine the survey program, identify the bridge site engineering geological conditions, its content should be consistent with the relevant provisions of Article 5.2.1 of these regulations.
6.2.2 detailed survey stage engineering geological mapping ratio should not be less than 1:2000, the bridge main pier, anchor idyll and other important parts or topographic changes in large sections should be 1:500i:io00 / strengthen the deepening of mapping work.
7 Construction survey
7.0.1 Construction survey should be carried out for the special requirements of construction plan, construction method, construction process and engineering geological problems arising during construction of the highway crossings, to meet the requirements of design and construction plan adjustment and risk control.
7.0.2 The construction survey shall be carried out in accordance with the requirements of design and construction in the following cases:
1 The geological conditions change significantly during the construction process and the original design and construction plan needs to be modified.
2 The presence of karst and other undesirable geological formations that are particularly complex and affect engineering safety.
3 The site has isolated rocks, drifting rocks, spherical weathering bodies, fracture zones, deep weathering channels and other special geological bodies that may adversely affect the construction of the project.
4 The construction plan has been greatly changed and the detailed survey data cannot meet the requirements.
5 Project precipitation, soil freezing, shield start (receiving) a total of end, contact channel and other sections of geotechnical reinforcement auxiliary method needs.
6 Artificial island construction and filling survey.
7 Other conditions requiring construction surveys.
8 Adverse geology
8.1 - general provisions
8.1.1 If there are adverse geological conditions at or near the highway crossing site that adversely affect the safety of the project and cannot be avoided, an adverse geological survey shall be carried out.
8.1.2 The adverse geological investigation shall identify the seasonal geological effects and adverse geological bodies that have an impact on the proposed works, including karst, strong seismic zone, seismic liquefaction, harmful gas, bank instability and radioactivity.
8.1.3 The investigation of adverse geology shall adopt a comprehensive investigation method combining data collection and analysis, engineering geological mapping, physical exploration, drilling, sampling and testing, and in-situ testing. According to different types of falsification. Determine the specific work content and workload and carry out work in a targeted manner.
8.1.4 Adverse geological investigation shall identify the causes, types, distribution range, scale and characteristics of the adverse geological effects existing at or near the Ermou site, and carry out special investigation and research work in stages according to the type of adverse geological effects in accordance with the feasibility study stage, preliminary investigation stage and detailed investigation stage.
8.2 Karst
8.2.1 When karst is developed along the highway cross-harbour passage project, karst investigation shall be carried out in conjunction with geological conditions, design and construction plans.
9 Special geotechnical characteristics
9.1 General provisions
9.1.1 The highway cross-harbour passage shall identify special geotechnical soils that have an impact on the construction of the project, including soft soils, fill soils, weathered rocks and residual soils, expansive soils, mixed soils, etc.
9.1.2 The investigation of special geotechnical soils distributed in the land area shall conform to the relevant provisions of the current Specification for Geological Investigation of Highway Projects (JTcc20).
9.2 Soft soils
9.2.1 Soft soil surveys in marine areas may be carried out in accordance with the relevant provisions of Article 3.7.4 of these Regulations by means of suitable static touching.
9.3 Fill
9.3.1 In addition to the relevant provisions of the current Code of Practice for Geological Investigation of Highway Projects (JTGC20), the survey of marine fill shall also include the following work:
1 Identify the topography and geological information of the site before filling.
2 Identify the source of the fill, _ the age of the pile and the filling method.
Appendix A Highlights of seabed-based static touch tests
Appendix B Key points of fixed static touch test in sea area
Appendix C Key points of seabed side pressure test
Appendix D Key points of flat shovel lateral expansion test in sea area
Appendix E Key points of cross-plate shear test in sea area
Appendix F Standard penetration test to determine the characteristic value of foundation bearing capacity
Appendix G Characteristic values of foundation bearing capacity determined by power touch test
1 General
2 Terminology and symbols
3 Basic provisions
4 Pre-survey and engineering survey
5 Preliminary survey
6 Detailed survey
7 Construction survey
8 Adverse geology
9 Special geotechnical characteristics
Appendix A Highlights of seabed-based static touch tests
Appendix B Key points of fixed static touch test in sea area
Appendix C Key points of seabed side pressure test
Appendix D Key points of flat shovel lateral expansion test in sea area
Appendix E Key points of cross-plate shear test in sea area
Appendix F Standard penetration test to determine the characteristic value of foundation bearing capacity
Appendix G Characteristic values of foundation bearing capacity determined by power touch test
