(2) The construction of cement concrete panel in high temperature period shall be avoided..
(5) If the road works are damaged, they shall be repaired in time.
（4） Asphalt concrete surface course (1) the asphalt mixture surface course of urban expressway and trunk road shall not be constructed in winter.
The operation procedures in rainy season shall be closely connected, and the pouring, vibration, plastering and curing shall be carried out in time.
Antifreeze and early strength agent can be added, and the mixing time shall be extended appropriately.
When the curing period of the above materials enters the winter period, antifreeze shall be added to the base material during the base construction.
(2) The construction of cement stabilized soil (granular) base should be stopped 15 ~ 30 days before entering the winter period.
(3) In winter construction, we should not only freeze, but also quickly, so as to ensure the quality.
Canopy shall be erected in the stockyard and mixing plant, or movable canopy shall be erected on the construction site.
（3） Base course construction (1) for the base course of stable materials, we should adhere to the number of mixing, paving, pressing and completion.
(2) Adjust the construction steps and concentrate on sectional construction.
In the section with churning due to rain, it is necessary to refuel and redo.
(2) The cement concrete mixing plant shall frequently measure the moisture content of coarse and fine aggregates, and adjust the water addition in time to ensure the accuracy of mix proportion.
3、 Construction in high temperature period (I) provisions for construction of cement concrete pavement (1) when the temperature is higher than 30 ℃, the temperature of concrete mixture is 30-35 ℃, and the relative humidity of air is less than 80%, it shall be carried out in accordance with the provisions for construction in high temperature period.
(3) For the construction of graded sand (gravel) and graded crushed stone, the antifreeze solution shall be distributed according to the minimum temperature of the construction environment, and the antifreeze solution shall be distributed and rolled at the same time.
(3) The subgrade of urban expressway and trunk road shall not be filled with soil materials containing frozen soil blocks.
(2) Winter construction of tack coat, prime coat and seal coat is strictly prohibited.
（2） Subgrade construction (1) for the construction of soil subgrade, it is necessary to organize the rapid construction in a planned way, excavate in sections, and avoid full excavation or too long excavation section.
construction quality control in rainy season (I) basic requirements for construction in rainy season (1) strengthen contact with meteorological stations, master weather forecast and arrange construction when it doesn’t rain.
Supplement: when the asphalt pavement must be constructed in winter, appropriate measures shall be taken to increase the mixing, delivery and construction temperature of the asphalt mixture, cover the insulation during transportation, and take measures such as rapid unloading, rapid paving, rapid leveling and rapid compaction.
(2) During construction, thermal insulation and anti freezing measures shall be taken according to the temperature change.
(2) If the design elevation cannot be reached on that day, the operating surface shall be planed loose or covered before work to prevent freezing.
（3） Base course construction (1) lime and lime fly ash stabilized soil (granular material, steel slag) base course should be stopped 30 ~ 45d before entering the winter period, and shall not be constructed in the winter period.
Prepare rainproof facilities such as rainproof shed before construction.
In rainy season, the construction length shall be shortened, the contact between the construction site and the asphalt mixing plant shall be strengthened, and the paving and rolling shall be completed in time.
The world is so big, in case of separation.
(4) Establish and improve the drainage system and combine prevention and drainage; The patrol inspection shall be strengthened, and the ponding and water retaining places shall be dredged in time.
The minimum temperature of concrete surface during curing period shall not be lower than 5 ℃.
Rain proof measures shall be taken for transport vehicles.
(II) subgrade construction (1) excavate frozen soil mainly by machinery and supplemented by labor, and roll it into shape immediately after reaching the design elevation.
(3) the temperature of concrete mixture should not be higher than 35 ℃.
When the day and night average temperature is lower than – 5 ℃ or the minimum temperature is lower than – 15 ℃, the construction should be stopped.
Sand and stone with ice and snow shall not be used in the mixture.
(6) Try to shorten the time of each process and construct quickly.
(2) When the daily average temperature is lower than 5 ℃ for 5 consecutive days or the minimum ambient temperature is lower than – 3 ℃, it shall be regarded as entering winter construction.
（4） Surface course construction (1) the asphalt surface course shall not be constructed when it rains or the lower layer is wet.
During the construction of road mixing method, the water on the surface of the lower bearing layer shall be drained to prevent the aggregate from being too wet.
(2) Cross slope and intercepting ditch shall be reserved in the excavation section.
The construction shall be stopped during rainfall, and the paved cement mixture shall be compacted as soon as possible.
(3) In rainy areas, lime soil base construction in rainy season shall be avoided; When lime is used to stabilize medium grained soil and coarse-grained soil, measures to drain surface water shall be taken to prevent excessive moisture of aggregate, and lime shall be protected from rain.
(3) Rain proof preparation shall be made.
2、 Winter construction quality control (I) basic requirements for winter construction (1) earthwork and soil foundation construction projects shall be completed before freezing as far as possible.
Click “Cao Mingming Municipal Administration” at the top → click “…” at the upper right corner Click “set as star Mark ★” (corresponding to lecture 26 of intensive lecture class) 1k420094 construction quality assurance measures in winter and rainy season I.
(2) When it rains too late to complete, it shall be rolled as soon as possible to prevent rainwater infiltration.
（5） Cement concrete surface course (1) the mixing plant shall be provided with a shed or other wind proof equipment.
When the construction temperature of secondary trunk road and roads below it is lower than 5 ℃, the construction shall be stopped.
After forming, the thermal insulation layer shall be covered in time to slow down the heat loss and make the strength of concrete reach the design strength before its temperature drops to 0 ℃.
The discharge temperature of the mixer shall not be lower than 10 ℃ and the paving concrete temperature shall not be lower than 5 ℃.
(3) The construction of filling section shall be leveled and compacted according to the cross slope of 2% ~ 3% to prevent ponding.
(4) When constructing cement stabilized soil, especially cement soil base course, in rainy season, special attention shall be paid to weather changes to prevent cement and mixture from being drenched by rain.
(4) When the flexural tensile strength of concrete slab is lower than 1MPa or the compressive strength is lower than 5MPa, it shall not be frozen.
Insist on digging and pressing on the same day, leaving no future trouble.
The paving time shall be arranged when the temperature is high within a day to ensure that the asphalt surface has sufficient rolling temperature and compactness.
(4) Prepare materials such as antifreeze cover, wind proof, heating and thermal insulation.
(5) Before concrete slab pouring, the base course shall be free from freezing and ice and snow, and the temperature during concrete paving shall not be lower than 5 ℃.
When the wind force is level 6 or above, the asphalt mixture surface course shall not be constructed.
