1 General provisions
1.0.1 This specification is formulated in order to implement the national policies on technical, economic and social development, scientifically and reasonably design intersections on urban roads, and realize people orientation, reasonable economy, safety, reliability, land conservation, beauty and environmental protection by using advanced technologies.
1.0.2 This specification is applicable to the design of new and renovated intersections on urban roads. New intersections must be designed in accordance with the requirements of this specification; in case of limited conditions for renovated intersections, the technical indexes of short-term design may be adjusted reasonably, but the long-term renovation design shall meet the requirements of this specification.
1.0.3 The design of intersections on urban roads shall be consistent with the urban master planning and shall meet the requirements in terms of the types, grades, boundary line widths, cross-sectional combinations and control elevation of intersected roads, the positions, traffic functions and planned range of land use of intersections in the urban road network determined by urban traffic planning. The following requirements shall also be met:
1 In the design of intersections on urban roads, main technical indexes shall be reasonably selected based on the forecast traffic volume, direction and characteristics, actual terrain and its features and the requirements for environmental protection.
2 In the design of intersections on urban roads, the relationship among people, vehicles, roads and environment shall be properly handled in accordance with the traffic organization design and traffic engineering requirements.
3 Road planes, profiles and cross-sections within the intersections on urban roads shall be subjected to integrated design and coordinated with each other. For interchanges, perspective drawing should be used check the coordination between design modeling and surrounding landscape. The control elevation in the design shall fit with ground drainage, underground pipelines and surrounding buildings and structures, etc.
4 When phased construction is adopted, an overall design scheme must be made according to the planning, and then corresponding phased construction design shall be carried out according to the near- and long-term traffic volume and fund raised. Phased construction design shall allow the works to be completed in early phase to be made full use of in later phase and to leave room for control and create favorable conditions for the construction of works to be completed in later phase.
1.0.4 In addition to this specification, the design of intersections on urban roads shall also meet the requirements specified in current relevant standards of the nation.
2 Terms
2.0.1 key interchange
key traffic node where expressways intersect expressways, freeways or strategic trunk roads in megacities and big cities for main line traffic flows pass by layers
2.0.2 common interchange
traffic transition node where an urban trunk road or secondary trunk road intersects an urban expressway or freeway for main line traffic flows pass by layers
2.0.3 signalized intersection
intersection using traffic signals to organize and direct the running order of conflicting traffic flows
2.0.4 stop sign intersection
intersection, where a main road intersects a secondary road, using stop and yield signs to organize and allocate the passing time of conflicting traffic flows, and requiring that vehicles on the secondary road must stop and observe to ensure safety before driving on the intersection
2.0.5 uncontrolled intersection
intersection without any traffic control measures, where traffic flows in various directions pass in the order specified by traffic laws and regulations
2.0.6 traffic island
various island-like facilities arranged on the road surface for channelizing and separating traffic flow and for pedestrians to stop before crossing the street, which may be structures or lines drawn on roads and can be divided into center island, channelization island and refuge island based on functions
2.0.7 channelinged design at road intersection
design using means such as marking, signs, physical facilities and local widening of the entrance end to diverge and guide traffic flows, so as to eliminate the mutual interference between traffic flows in all directions at intersections. The design content includes lane function division, directional marking and directional island
2.0.8 left turn vehicles stopped ahead crosswalk line waiting for green light
method, to improve the traffic capacity of a large intersection controlled by signal lights, in case of heavy traffic of left turn vehicles, a proper amount of left turn vehicles cross the crosswalk line (the straight stop line at the entrance end in the same direction if there is no crosswalk line) to park and wait for driving, so that when the green light is on, the left turn vehicles waiting for driving ahead can pass the conflict point before the opposite straight vehicles reach the conflict point between left turn and going straight
2.0.9 center line of road deflective method
marking measure to shift the center line of roads towards the exit lanes in the channelinged design at road intersection in order to increase the number of lanes in the entrance lanes and thus improve the traffic capacity
2.0.10 auxiliary lane
lane added on the main line side at the upstream of the diversion section and downstream of the confluence section of an interchange in order to balance the number of lanes on the main road upstream and downstream of the ramp and keep the basic number of lanes on the main line
2.0.11 collection-distributed lane
lanes, parallel to and laterally separated from the main line and connected with the main line at both ends, set on one side or both sides of the main line for vehicles entering and leaving the main line to run in order to reduce the number of entrances and exits on the main line of an interchange and the interweaving of traffic flow
2.0.12 variable velocity lanes
additional lanes (including transition zone), at the entrances and exits of an interchange, for vehicles to enter and exit the main line for acceleration and deceleration
2.0.13 interweaved section
road section, in an interchange, from the wedge-shaped end on the confluence side to the wedge-shaped end on the diversion side, used for vehicles to interweave from confluence to diversion
2.0.14 detour type interchange
basic form of interchange, characterized in that the left turn vesicles need to turn right to be far away from the intersection and then turn around to 180° to realize the left turn
2.0.15 relief road
one-way or two-way roads for collecting and distributing expressway traffic, which are set on both sides or one side of expressway, including, as required, intermittent relief roads between two interchanges or continuous relief roads passing through interchanges
3 Basic requirements
3.1 Classification and selection of road intersections
3.1.1 Intersection on urban roads should be divided into two types: intersections and interchanges, which shall be reasonably determined according to the planning of road traffic network, the grade of intersecting roads and the analysis of relevant technical, economic and environmental benefits.
3.1.2 Intersections shall be classified according to the traffic organization mode, and shall meet the following requirements:
1 Class A: signalized intersections
Class A1 intersection: controlled by traffic signals, intersection widened at entrance lane.
Class A2 intersection: controlled by traffic signals, intersection not widened at entrance lane.
2 Class B: unsignalized intersections
Class B1 intersection: a type of intersection where the center of the trunk road is isolated and closed and the branch road is only allowed to turn right (hereinafter referred to as “right turn intersection”).
Class B2 intersection: a type of intersection controlled by yield sign or stop and yield sign (hereinafter referred to as “yield intersection”).
Class B3 intersection: uncontrolled intersection.
3 Class C: roundabouts
Class C intersection: roundabouts.
3.1.3 The type of intersections selected shall meet those specified in Table 3.1.3.
Foreword ii
1 General provisions
2 Terms
3 Basic requirements
3.1 Classification and selection of road intersections
3.2 Design principles
3.3 Design vehicle, design speed and design life
3.4 Construction clearance and seismic fortification
4 Grade crossing
4.1 Design principles
4.2 Traffic organization and design of entrance and exit lanes
4.3 Grade and vertical design
4.4 Arrangement of bus stops and exclusive lanes
4.5 Crossing facilities for pedestrian and non-motor vehicles
4.6 Roundabout
4.7 Ancillary facilities
4.8 Grade crossing under viaduct
5 Grade separation
5.1 Cross section of main line
5.2 Horizontal and vertical alignment of main line
5.3 Ramp
5.4 Auxiliary lane
5.5 Variable velocity lane and collection-distributed lane
5.6 Service level and traffic capacity
5.7 Ancillary facilities
6 Intersection between road and railway
6.1 Design principle
6.2 Grade crossing
6.3 Grade separation
Annex A Evaluation of grade separation scheme
Annex B Figures of ancillary facilities structure in grade separation
Explanation of wording in this specification
List of quoted standards
