Detail of JTG D81-2017

Introduction of JTG D81-2017

Codeofchina.com is in charge of this English translation. In case of any doubt about the English translation, the Chinese original shall be considered authoritative. According to the requirements of Document TINGGONGLUZI [2011] No.115 issued by the Ministry of Transport - "Notice on Issuing the Development and Revision Plan of Highway Engineering Standards in 2011", the Research Institute of Highway Ministry of Transport is in charge of the revision work of JTG D81-2006 Specification for Design of Highway Safety Facilities as the development organization. The Specifications is a full revision of the former JTG D81-2006 Specification for Design of Highway Safety Facilities, shall be issued and implemented in the name of JTG D81-2017 Design Specifications for Highway Safety Facilities after being approved. During revision, the revision group closely combined the characteristics and development trends of China's highway operation environment, as well as the functions, technical conditions, traffic conditions and topographical conditions of various grades of highways, comprehensively summarized the relevant domestic scientific research and design achievements since the implementation of JTG D81-2006 Specification for Design of Highway Safety Facilities, absorbed and borrowed the advanced experience and standards and specifications of developed countries, carried out special research on key technical issues, extensively solicited the comments of competent departments, highway construction and operation management organizations, and highway design and scientific research organizations in the transportation industry nationwide, discussed, modified and pre-designed the Specifications repeatedly, and finalized the Specifications finally through review. The Specifications comprises 12 chapters (General Provisions; Terms; Overall Design; Traffic Signs; Traffic Markings; Barriers and Railings; Visual Guiding Devices; Fencing; Preventing Fallen Object Fence; Anti-glare Facility; Escape Lane; and Other Traffic Safety Facilities) and 1 annex. The following main revisions have been made with respect to the former specification: 1. According to the JTG B01-2014 Technical Standard of Highway Engineering, the order of the chapters and sections is adjusted, to highlight the use functions of various types of traffic safety facilities. 2. The chapter - “Overall Design” is added to strengthen coordination and connection with highway civil engineering, highway management facilities and service facilities. 3. In the chapters - “Traffic Signs” and “Traffic Markings”, the principle content is emphasized and their roles as traffic safety facilities are highlighted. 4. In line with JTG B05-01-2013 Standard for Safety Performance Evaluation of Highway Barriers, the “anti-collision grade” of the barriers is adjusted to “protection grade” and the protection grades of the barriers are added; the conditions for arrangement and determination of protection grade of roadside barrier are more detailed to increase the operability; the structural requirements for various types of bridge barriers are refined; the protective performance of moveable highway barrier of median opening is specified; and the content of “impact attenuator” is added. 5. The former chapter - “Delineator” is restored to “Visual Guiding Devices” with appropriate extension of the coverage to enhance the edge indication of special road sections such as tunnels. 6. The height and grid specification of fencing are appropriately adjusted according to the characteristics of the isolated objects in different areas, and the requirement for arranging the “movable door” is added. 7. The scope of the preventing fallen object fence is expanded to two categories: preventing fallen article fence and preventing fallen stone fence. 8. The chapter - “Escape Lane” is added, specifying the arrangement position, structural composition, horizontal and vertical alignment, length, paving materials and ancillary facilities design of the escape lane. 9. The chapter - “Other Traffic Safety Facilities” is added, specifying the arrangement principles and scale of traffic safety facilities such as wind fence, snow fence, snow marker post, height limit gantry, speed hump and convex mirror. During the process of implementing the Specifications, all organizations concerned are kindly requested to send the problems found and opinions by letter to the routine management group of the Specifications (contact: Liu Xuehui; address: Research Institute of Highway Ministry of Transport, No.15, East Huayuan Road, Haidian District, Beijing, 100191, China; Tel.: 62062052; Fax: 62370155; e-mail: hx.liu@rioh.cn) for reference in the future revision. Contents 1 General Provisions 1 2 Terms 3 3 Overall Design 6 3.1 General Requirements 6 3.2 Characteristic Analysis of the Project and Highway Network 6 3.3 Design Objectives 7 3.4 Arrangement Scale 7 3.5 Structural Design Standards 8 3.6 Design Coordination and Interface Division 12 4 Traffic Signs 13 4.1 General Requirements 13 4.2 Arrangement Principles 14 4.3 Layout Design 15 4.4 Materials 17 4.5 Supporting Methods and Structures 18 5 Traffic Markings 20 5.1 General Requirements 20 5.2 Arrangement Principles 21 6 Barriers and Railings 25 6.1 General Requirements 25 6.2 Subgrade Barrier 25 6.3 Bridge Barriers and Railings 30 6.4 Moveable Highway Barrier of Median Opening 39 6.5 Impact Attenuators 40 7 Visual Guiding Devices 42 7.1 General Requirements 42 7.2 Arrangement Principles 42 8 Fencing 45 8.1 General Requirements 45 8.2 Arrangement Principles 45 9 Preventing Fallen Object Fence 47 9.1 General Requirements 47 9.2 Arrangement Principles 47 10 Anti-glare Facility 49 10.1 General Requirements 49 10.2 Arrangement Principles 49 11 Escape Lane 51 11.1 General Requirements 51 11.2 Arrangement Principles 51 12 Other Traffic Safety Facilities 53 12.1 Wind Fence 53 12.2 Snow Fence 53 12.3 Snow Marker Post 54 12.4 Height Limit Gantry 54 12.5 Speed Hump 54 12.6 Convex Mirror 55 12.7 Other Facilities 55 Annex A Calculation Methods for Width of Clear Zone 56 Explanation of Wording in the Specifications 59 1 General Provisions 1.0.1 The Specifications is formulated with a view to standardizing the design of highway safety facilities and giving full play to the functions of traffic safety facilities. 1.0.2 The Specifications is applicable to the design of highway safety facilities for all grades of constructed, renovated and expanded highways. 1.0.3 The design contents of highway safety facilities shall include traffic signs, traffic markings (including raised pavement markers), barriers and railings, visual guiding devices, fencing, preventing fallen object fence, anti-glare facility, escape lane and other traffic safety facilities (including wind fence, snow fence, snow marker post, height limit gantry, speed hump and convex mirror). 1.0.4 The overall design of highway safety facilities shall be carried out in combination with the technical conditions, topographical conditions, traffic conditions and environmental conditions of the highway network and highways. The traffic safety facilities shall be used in a coordinated and cooperated way with each other and with the civil engineering and other facilities of the highway. 1.0.5 The design of highway safety facilities shall adhere to the principle of people orientation, prevention orientation, systematic design and key point emphasis. Based on the result of comprehensive traffic safety analysis, priority shall be given to the arrangement of active guidance facilities, and passive protection facilities shall be arranged as needed. 1.0.6 The design of traffic safety facilities for newly constructed highways should take into account the effects of highway operation and maintenance factors. The design of traffic safety facilities for renovated and expanded highways shall be carried out on the basis of investigation and comprehensive analysis of existing highway and in combination with the highway, traffic and environmental conditions after renovation and expansion, and shall include rational utilization and improvement of existing facilities. 1.0.7 The design traffic volume of highway safety facilities shall adopt that of the highway project, and the design vehicle overall dimension and representative vehicle type adopted shall meet the corresponding requirements of JTG B01 Technical Standard of Highway Engineering and JTG B05-01 Standard for Safety Performance Evaluation of Highway Barriers. 1.0.8 Under the conditions of meeting safety and use functions, the reliable new technologies, new materials, new processes and new products shall be actively promoted and used. 1.0.9 In addition to the requirements stipulated in the Specifications, the design of highway safety facilities shall also comply with those specified in the current relevant national and professional standards.   2 Terms 2.0.1 clear zone strip zone outside the highway carriageway, where no obstacle exists and vehicles can be parked or driven back to the highway after being driven out of the carriageway 2.0.2 standard sections of highway barriers structure section of highway barriers, in which the cross section structure remains unchanged and is continuously arranged within a certain length 2.0.3 transition sections of highway barriers structure section of highway barriers, which is arranged between two different structural forms or different protection grades, is smoothly connected, and has smooth transition of the structural stiffness 2.0.4 roadside barrier barrier arranged outside the roadside structure gauge 2.0.5 median barrier barrier arranged in the median barrier of the highway 2.0.6 moveable highway barrier of median opening structure section of highway barriers, which is arranged at the opening of median divider of the highway and has the opening function 2.0.7 rigid barrier a kind of barrier that is basically not deformed after being impacted by a vehicle, with the major representative type of concrete barrier, which absorbs the impact energy of vehicle through climbing motion and turning of the vehicle 2.0.8 semi-rigid barrier a kind of barrier that is deformed to a certain extent but is provided with certain strength and stiffness, with the major representative type of corrugated beam barrier, which absorbs the impact energy of vehicle upon the deformation of soil base, post and corrugated steel plate 2.0.9 flexible barrier a kind of tough barrier structure with relatively large buffer capacity, with the major representative type of cable barrier, which absorbs the impact energy of vehicle upon the tensile stress of cable 2.0.10 impact attenuator facility installed at the diverging nose end at the exit of highway interchange, service area and parking area, the head of toll island, or the end of barriers, etc. to reduce the impact and reduce the damages to the impacted vehicle and people inside the vehicle, with main forms of crashworthy terminal, crash cushion, etc. 2.0.11 crashworthy terminal facility that is arranged at the starting point facing the vehicle flow of barrier and is connected to the barrier to block, buffer and guide the impacted vehicle 2.0.12 crash cushion a kind of impact attenuator that is arranged in front of the obstacle at the highway traffic diverging site or the obstacle at other places, absorbs the impact energy of vehicle by self-deformation so as to reduce the degree of damage of the occupants and may be divided into redirective crash cushion and non-redirective crash cushion 2.0.13 traffic separation facilities facilities used for separating two-way or one-way traffic, motor vehicles and non-motor vehicles, and vehicles and pedestrians 2.0.14 visual guiding devices facilities indicating the highway alignment and contour and the traveling direction, mainly including delineator, converging guiding sign, alignment guiding sign, tunnel contour belt, warning pile, warning pier and intersection guard post 2.0.15 fencing facilities arranged on both sides of the highway to prevent people and animals from entering the highway or other prohibited areas along the line and to prevent illegal occupation of highway land 2.0.16 preventing fallen object fence facilities arranged on both sides of the highway bridge to prevent the thrown objects, sundries or transportation debris from entering the railway, navigable rivers or highways with large traffic volume under the bridge, which are referred to as preventing fallen article fence flexible protective facilities arranged on the cutting slope of highway to prevent the falling stone from entering the structure gauge of highway, which are referred to as preventing fallen stone fence preventing fallen article fence and preventing fallen stone fence are collectively referred to as preventing fallen object fence 2.0.17 anti-glare facility facility preventing the headlight glare of vehicles in opposite direction during night driving 2.0.18 wind fence facility arranged on the windward side or both sides of the highway to mitigate the influence of strong wind on the vehicles running on the highway 2.0.19 snow fence facility arranged on the windward side or both sides of the highway to mitigate the influence of snowdrift on the highway 2.0.20 snow marker post facility arranged on both sides of the highway in the road sections possibly with thick snow coverage to indicate the edges of highway pavement 2.0.21 speed hump arc-shaped raised area that is arranged on the carriageway or is extended to the entire highway pavement width, and is used in conjunction with corresponding traffic signs and markings to remind the drivers to control the vehicle speed   3 Overall Design 3.1 General Requirements 3.1.1 The highway safety facilities must be designed, constructed, and put into production and application at the same time as the highway civil engineering. 3.1.2 The highway safety facilities shall be subject to overall design. 3.1.3 The overall design of highway safety facilities shall be carried out on the basis of adequate collection of the planning, technical requirements, design drawings and traffic safety evaluation conclusions of the project and the highway network, as well as the on-site survey. 3.1.4 The overall design of highway safety facilities shall include the characteristic analysis, design objectives, arrangement scale, structural design standards, design coordination and interface division of the project and highway network. 3.1.5 In addition to the requirements stipulated in 3.1.4 herein, the overall design of renovated and expanded highway safety facilities shall also be based on the conclusions of investigation and comprehensive analysis on existing highway, including the reuse scheme of existing facilities and design scheme of temporary traffic safety facilities. 3.2 Characteristic Analysis of the Project and Highway Network 3.2.1 The analysis of the project-related data shall include the following: 1 The functions and orientation of the project in the highway network; 2 The scope of direct and indirect services of the project; 3 The distribution of important facilities such as traffic hubs, tourist attractions and drinking water source protection areas along the line of the project; 4 The technical standards, topographical conditions, traffic conditions and environmental conditions of the project. 3.2.2 The analysis of the relationship between the project and the highway network shall include the following: 1 The stake No. information transferred by the mileage from starting point to ending point; 2 The starting and ending point information of the coincident section; 3 The starting and ending point information of the cross-town section; 4 The route information constituting multiple paths; 5 The naming and numbering information of related routes; 6 The information about the highways, railways and waterways being crossed. 3.2.3 The comprehensive traffic safety analysis of the project from the perspective of the highway users shall include the following: 1 The safety risks and hidden dangerous road sections (points) that may exist during highway operation; 2 The safety design focus of traffic safety facilities. 3.3 Design Objectives 3.3.1 The design objectives of traffic safety facilities shall be proposed from the aspects such as service, safety, management, environment and cost in combination with the analysis results of project and highway network characteristics. 3.3.2 For the highway renovation and expansion projects, the design objectives of reusing existing traffic safety facilities and arranging temporary traffic safety facilities shall be proposed. 3.4 Arrangement Scale 3.4.1 The arrangement scale of highway safety facilities shall be reasonably determined according to the determined design objectives, taking into account factors such as the highway network planning, highway function, technical level, traffic volume, vehicle type composition and environment. 3.4.2 For the main arterial highways, systematic and perfect traffic signs, markings, visual guiding devices, fencing, and necessary preventing fallen object fence and anti-glare facilities shall be arranged according to the provisions of the Specifications; for the bridges and high-embankment road sections, roadside barriers must be arranged; where the central strip width of integral cross-section is less than or equal to 12m, the median barrier must be arranged continuously; in case of a connection between the barriers of different types, transition design shall be carried out; moveable highway barrier of median opening must be arranged; crash cushion shall be arranged at the exit triangular diverging end. 3.4.3 For the secondary arterial highways, perfect traffic signs, markings, visual guiding devices, and necessary fencing and preventing fallen object fence shall be arranged according to the provisions of the Specifications; for the bridges and high-embankment road sections, roadside barriers must be arranged; where the central strip width of integral cross-section of Class I highway is less than or equal to 12m, the median barrier must be arranged continuously; in case of a connection between the barriers of different types, transition design shall be carried out; moveable highway barrier of expressway median opening must be arranged; and anti-glare facility may be arranged for Class I highway as needed. 3.4.4 For the main collector-distributor highways, relatively perfect traffic signs, markings, and necessary visual guiding devices and fencing shall be arranged according to the provisions of the Specifications; for the bridges and high-embankment road sections, roadside barriers must be arranged; for Class I highway, traffic separation facilities ensuring driving safety shall be arranged at the central strip of integral cross-section. 3.4.5 For the secondary collector-distributor highways, relatively perfect traffic signs, markings and necessary visual guiding devices shall be arranged according to the provisions of the Specifications; for the bridges and high-embankment road sections, roadside barriers must be arranged. 3.4.6 For the branch highways, traffic signs shall be arranged according to the provisions of the Specifications; for the road sections with poor sight distance, sharp turn or steep slope, traffic markings and necessary visual guiding devices shall be arranged; and for the road sections with cliff, deep valley, deep trench, river, lake and sea not meeting the requirement for the calculated width of clear zone existing on the road side, roadside barriers shall be arranged. 3.4.7 For continuous long and steep downhill section of highway, it is necessary to demonstrate whether escape lane needs to be arranged according to the provisions of the Specifications in combination with the results of comprehensive traffic safety analysis. Where an escape lane is arranged, supporting traffic signs, markings, and traffic separation facility, protection facility, impact attenuator and other facilities shall be arranged. 3.4.8 For the road sections where the highway traffic safety is endangered by wind and snow, traffic safety facilities such as wind fence, snow fence and snow marker post shall be arranged according to the provisions of the Specifications; according to the requirements of operation management and traffic management, traffic safety facilities such as height limit gantry, speed hump and convex mirror may be arranged according to the provisions of the Specifications. 3.5 Structural Design Standards 3.5.1 The actions adopted in the structural design of highway safety facilities shall meet the requirements of Table 3.5.1. Except for the impact load of vehicle borne by the bridge barriers, the standard value, representative value and combined effect design value of other actions shall be calculated by reference to the current JTG D60 General Specifications for Design of Highway Bridges and Culverts. In case of any other non-negligible action in the structure, its standard value, representative value and combined effect design value shall be calculated according to the requirements of the relevant specifications. Table 3.5.1 Actions Adopted in Structural Design of Highway Safety Facilities Facility type Action name Action classification Barriers Structure gravity (including additional gravity of structure) Permanent action Soil gravity (subgrade barrier) Soil lateral pressure (subgrade barrier) Pre-applied force (cable barrier) Wind load Variable action Railing load of sidewalk and bikeway Impact load of vehicle Accidental action Traffic signs, preventing fallen article fence, fencing, anti-glare facility, wind fence, snow fence and height limit warning gantry Structure gravity (including additional gravity of structure) Permanent action Soil gravity (arranged at the soil base) Soil lateral pressure (arranged at the soil base) Wind load Variable action Temperature action Anti-crash height limit gantry Structure gravity (including additional gravity of structure) Permanent action Soil gravity (arranged at the soil base) Soil lateral pressure (arranged at the soil base) Permanent action Wind load Variable action Temperature action Impact load of vehicle Accidental action Raised pavement marker Wheel load of vehicle Variable action 3.5.2 The structural design safety grade of highway safety facilities shall comply with the current GB/T 50283 Unified Standard for Reliability Design of Highway Engineering Structures. The structural design safety grade may be adjusted according to the specific conditions of the location of the traffic safety facilities, but shall not be less than the grade specified in Table 3.5.2.   Table 3.5.2 Structural Design Safety Grade of Highway Safety Facilities Structural design safety grade Facility type Grade II Barriers, preventing fallen article fence, wind fence and snow fence arranged on grand bridge; Cantilever type and gantry type traffic signs arranged on expressway and Class I highway Grade III Other traffic safety facility structures 3.5.3 Permanent actions shall meet the following requirements: 1 The standard value of structure gravity may be determined through calculation according to the design dimensions of structural members and the material weight. 2 The pre-applied force, soil gravity and soil lateral pressure shall be calculated according to the current JTG D60 General Specifications for Design of Highway Bridges and Culverts. 3 The design of concrete barrier and steel-concrete composite barrier should take into account the shrinkage and creep of concrete. 3.5.4 Variable actions shall meet the following requirements: 1 The standard value of wind load shall be calculated according to the current JTG D60-01 Wind-resistant Design Specification for Highway Bridges, and the recurrence interval of basic wind pressure shall be 50 years. 2 The standard value of the vehicle wheel load on raised pavement marker shall be 70kN, and the wheel touchdown length×width shall be 0.6m×0.2m. 3 The standard value of temperature action shall be calculated according to the current JTG D60 General Specifications for Design of Highway Bridges and Culverts. 4 The standard value of horizontal thrust acting on the top of railing post on sidewalk and bikeway shall be 0.75kN/m, and that of vertical force acting on handrail shall be 1.0kN/m. 3.5.5 Accidental actions shall meet the following requirements: 1 The impact vehicle type, impact speed and angle of impact adopted for the structural design and safety performance evaluation of barriers shall meet the requirements of the current JTG B05-01 Standard for Safety Performance Evaluation of Highway Barriers. Where the vehicle composition of a specific road section of highway does not include a certain specified impact vehicle type, the structural design and safety performance evaluation of barriers may not take this vehicle type into account. 2 During the design of bridge barrier specimen, the standard value of lateral impact load of the vehicle born by the specimen shall meet the requirements of Table 3.5.5. On the basis of comprehensive analysis of factors such as highway alignment, roadside hazard degree, operating speed, traffic volume and vehicle composition, where the protection grade of barriers adopted is lower than Grade 1(C), the lateral impact load of vehicle shall be calculated according to Grade 1(C); where the protection grade of barriers adopted is higher than Grade 8(HA), the lateral impact load of vehicle shall be determined according to the actual impact conditions.

Contents of JTG D81-2017

Contents 1 General Provisions 2 Terms 3 Overall Design 3.1 General Requirements 3.2 Characteristic Analysis of the Project and Highway Network 3.3 Design Objectives 3.4 Arrangement Scale 3.5 Structural Design Standards 3.6 Design Coordination and Interface Division 4 Traffic Signs 4.1 General Requirements 4.2 Arrangement Principles 4.3 Layout Design 4.4 Materials 4.5 Supporting Methods and Structures 5 Traffic Markings 5.1 General Requirements 5.2 Arrangement Principles 6 Barriers and Railings 6.1 General Requirements 6.2 Subgrade Barrier 6.3 Bridge Barriers and Railings 6.4 Moveable Highway Barrier of Median Opening 6.5 Impact Attenuators 7 Visual Guiding Devices 7.1 General Requirements 7.2 Arrangement Principles 8 Fencing 8.1 General Requirements 8.2 Arrangement Principles 9 Preventing Fallen Object Fence 9.1 General Requirements 9.2 Arrangement Principles 10 Anti-glare Facility 10.1 General Requirements 10.2 Arrangement Principles 11 Escape Lane 11.1 General Requirements 11.2 Arrangement Principles 12 Other Traffic Safety Facilities 12.1 Wind Fence 12.2 Snow Fence 12.3 Snow Marker Post 12.4 Height Limit Gantry 12.5 Speed Hump 12.6 Convex Mirror 12.7 Other Facilities Annex A Calculation Methods for Width of Clear Zone Explanation of Wording in the Specifications