Summary of Common Technical Parameters in Municipal Engineering Construction 1Warm-mix asphalt mixture surface layer: Warm-mix asphalt mixture produces foaming lubrication by adding synthetic zeolite in the mixing process. The asphalt mixture produced under mixing temperature 120-130 degrees C has the same application range as hot-mix asphalt mixture. 2Fiber stabilizers do not deteriorate at 250 C. 3Capillary water can rise to a certain height in the direction of Counter-gravity under capillary action, and can still move and accumulate below 0 C, resulting in frost heave. 4Lime stabilized soil has good slab properties, but its water stability, frost resistance and early strength are not as good as cement stabilized soil.The strength of limestone soil increases with age and is closely related to curing temperature. The strength hardly increases when the temperature is lower than 5 C. 5The early strength of lime-fly ash stabilized soil is lower, but the strength increases with age and is closely related to the curing temperature. The strength hardly increases when the temperature is lower than 4 C. The more the amount of fly ash used in lime-fly ash, the lower the early strength, the greater the strength increase during the three- month period. 6Lime stabilized soil base, cement stabilized soil base and lime fly ash stabilized gravel (gravel) base should be constructed at the end of spring and in the high temperature season, with the lowest temperature being 5 C. 7Geotechnical network or geogrid should be selected as reinforcement material. The tensile strength (kN/m2) should be greater than 6 (longitudinal) and 5 (transverse), and the tensile modulus (kN/m) should be greater than 100 at 20 C. 8Geotextiles should be able to withstand high temperatures above 170 C. 9The ironing plate of the paver should be pre- heated 0.5-1 h before paving the asphalt mixture surface so that it is not less than 100 C. 10The lowest paving temperature is 140 C, 135 C and 130 C when the surface temperature of the underlying layer is 15-20 C, the thickness of the paving layer is less than 50 mm, 50-80 mm and more than 80 mm respectively. 11Hot mix asphalt mixture pavement should wait for paving layer to cool down naturally until the surface temperature is below 50 degrees Celsius before traffic can be opened. 12The production temperature of modified asphalt mixture should be increased by 10-20 C compared with that of ordinary asphalt mixture. 13The mixer should be equipped with a warehouse of finished products with good thermal insulation. During storage, the temperature drop of the mixture should not be greater than 10 C, and it has the function of bitumen dripping and leaking. 14The construction temperature of modified asphalt SMA mixture should be determined by test. Generally, the paving temperature should not be lower than 160 C.The initial pressing temperature should not be less than 150 C, and the surface temperature at the end of rolling should not be less than 90 - 120 C. 15According to the construction progress, traffic volume, distance and road condition, the vehicle type and the total number of vehicles should be selected.The maximum allowable time for concrete mixtures of different paving processes from the discharging of mixer to the completion of paving shall be in accordance with the regulations.For example, when the construction temperature is 10- 19 C, the construction of sliding form and track machinery is 2.0 h, the construction of three-bar shaft units and small machines is 1.5 h, the former is 15 h at 20-29 C, the latter is 1.25 h, and the former is 1.25 h at 30-35 C, and the latter is 1.0 H. 16Thermal insulation and maintenance measures should be adopted for concrete slabs constructed in areas where the temperature difference between day and night is greater than 10 degrees Celsius or where the daily average temperature is lower than 5 degrees Celsius. 17When the temperature is lower than 5 C, thermal insulation measures should be taken, and concrete should not be sprinkled and maintained. 18In the course of grouting and within 48 hours after grouting, the temperature of structural concrete should not be lower than 5 C, otherwise thermal insulation measures should be taken.When the daytime temperature is higher than 35 C, grouting should be carried out at night. 19When laying waterproof membrane, the ambient

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