Highway maintenance 1, what is highway maintenance? Answer: Highway maintenance refers to regular maintenance, repair, prevention and repair of catastrophic damage to ensure the normal use of highways, as well as reinforcement, improvement and addition to improve the quality of use and service level. 2. What is the daily maintenance in expressway? Answer: Daily maintenance of highway refers to regular maintenance and repair of the slightly damaged parts of highway and facilities along the route. Including finishing the shoulder, dredging the side ditch, clearing weeds, repairing pits and grooves, pruning flowers and plants, greening, cleaning signs and so on. 3, highway maintenance projects are divided into several categories? Answer: Highway maintenance is divided into four categories according to its engineering nature, scale and technical difficulty: minor maintenance, medium maintenance, overhaul and reconstruction. 4. What is the purpose and basic task of highway maintenance? Answer: (1) Always keep roads and their facilities in good condition, repair damaged parts in time, and ensure safe, comfortable and smooth driving. (2) Take correct technical measures to improve the quality of maintenance work, thus prolonging the service life of the highway. (3) Combining prevention with control, treating patients existing in highways and gradually improving the disaster resistance of highways. (4) Improve and build sections and structures with low original technical standards and facilities along the line by stages, and gradually improve the quality of use and service level of highways. 5. What are the quality requirements for highway maintenance? Answer: Highway maintenance quality requirements are generally implemented in accordance with the Standard for Inspection and Evaluation of Highway Maintenance Quality (JTJ 075-94). The quality requirements mainly include: keeping the pavement clean, with moderate cross slope and comfortable driving; Shoulder clean, slope stability, smooth drainage; Structures, bridges and tunnels are in good condition; Perfect facilities along the line; Greening is harmonious and beautiful. Strive to form a smooth, clean, green and beautiful highway traffic environment. 6. What are the basic requirements for subgrade maintenance? Answer: (1), all parts of subgrade: always intact, the dimensions of all parts are kept in the specified standard requirements, without damage or deformation, and always in good condition. (2) Shoulder: the cross slope should be moderate, the edge should be straight, and the connection with the road surface should be smooth; The surface is solid, flat, clean and free of tall grass; Keep no ruts, potholes, bulges, sags and gaps. (3) Slope: the slope meets the specified requirements; The slope is smooth, stable and firm; No ravines, no collapses. (4) Drainage system: the longitudinal slope is moderate and the drainage is smooth; Drainage facilities without sundry, no silt floating objects; Import and export are good, and there is no water in the side ditch. (5) Protective structure: kerbs, retaining walls and other structures remain intact; Masonry expansion joints such as slope protection, snow prevention and sand prevention facilities are well filled; The drain hole is not blocked. (6) Subgrade diseases: general disease areas should be treated in time and repaired as soon as possible; Prevention, treatment and emergency repair of frost boiling, landslide, debris flow and water damage, so as to shorten the traffic jam time as much as possible. 7. What are the basic requirements for pavement maintenance? Answer: (1), maintain and repair the pavement in time and often, keep the pavement flat, with moderate cross slope, straight line, clean road capacity and good drainage. Prevent the occurrence and development of various diseases such as loose pavement, cracks and packages. (2) Through the maintenance and repair of the pavement, the smoothness and skid resistance of the pavement are maintained and improved, and the safe and comfortable driving performance of the pavement is ensured. (3) By repairing and improving the pavement, the strength of the pavement is maintained and improved, and the durability of the pavement is guaranteed. (4) Prevent pavement damage and environmental pollution caused by maintenance. (5) Strengthen road patrol inspection, master the road conditions, eliminate all kinds of factors that damage the road surface at any time, and repair the road surface as soon as possible when initial diseases are found. 8. What is unclean shoulder? Irregular? Answer: Dirty shoulder means that there are sundries, rubbish, deposits and tall grass over 15cm on the shoulder. Irregularity refers to the uneven connection between the shoulder and the road surface, which is more than 2cm below the road surface (the black hardened shoulder is less than 1cm) or higher than the road surface; The transverse slope is smaller than the pavement transverse slope; Non-uniformity and non-compactness affect lateral drainage; The shoulder width is less than the design width; The outer edge of the shoulder is not suitable, and the width difference is more than 20cm. 9. What does the regular inspection of bridges include? Answer: (1), whether the bridge deck pavement is smooth, whether there are cracks, local pits, waves and gravel, and whether there are bumps at the bridge head; (2) Whether the bridge deck drainage pipe (hole) is blocked or damaged; (3), the bridge deck is clean, with or without debris accumulation, weeds; (4), whether the expansion joint is blocked, whether the joint is loose and local damage; (5) Whether sidewalks, kerbs, railings, handrails and approach guardrails (columns) are damaged, broken, loose, missing parts, falling off and corroded; (6) Whether the wing wall (side wall and ear wall) is cracked, weathered, peeled off and deformed abnormally; (7), cone slope, slope protection for local collapse, pavement collapse, defects, garbage and weeds, bridge drainage and pedestrian steps are in good condition; (8), traffic signals, signs, markings, lighting facilities are in good condition. 10, what are the contents of bridge superstructure inspection? Answer: (1), check the superstructure of reinforced concrete and prestressed concrete, and check whether the concrete has water seepage, cracks, surface weathering, peeling, rebar exposure and rebar corrosion, and whether there is overall cracking caused by the silica-alkali reaction of active aggregate. (2), check the span, fulcrum, variable cross-section, cantilever end, bracket or middle part, steel structure, and concrete cracks and steel corrosion at joints and nodes. (3) Whether the concrete in the anchorage section of prestressed steel bar is cracked and whether there are longitudinal cracks on the surface of prestressed concrete. (4) Precast beams and bridges should pay attention to the defects in the connection parts. (5) The arch bridge mainly checks the deformation of the main arch foot, L/4, 3L/4, arch ring and the structure on the arch, as well as the defects such as concrete cracking and steel bar corrosion.