Surveying and setting out
Before the construction of corrugate pipe culvert, the center line position and longitudinal and transverse axes of the corrugated pipe culverts should be confirmed on site surveying. According to the requirements of the design and relevant standards, the slope of the foundation pit should be appropriately steepened. And the foundation pit width is the same with the size of flipped foundation, When filling, fully consider the thickness of the replacement to ensure that the size is sufficient at once
Working on the foundation pits
The excavation of the foundation pit is carried our using manual and mechanical methods, slopes in areas with small depth and good soil quality, vertical excavation can be adopted the slope structure in deep and watery areas, slope according to the properties of the soil and appropriate slope ratio.
Base treatment
Gravel can be used to replace and compact the foundation normally base.The rock foundation needs to be over excavated by more than 30cm, the over excavation.thickness should be increased according to the filling height, then replace and compact with sand and gravel.Soft soil foundation can be treated with plastic inserts or gravel piles.
Assembly of corrugated pipe culverts
Before assembly the corrugated pipe culverts, check the bottom flatness, standard height,inspection of the setting of high and pre arches.Accurately determine the center of the corrugated pipe culvert,using the central axis as the reference, assemble the bottom plate:locate the first corrugated plate , using it as the starting point to extend towards both ends, At both ends of the inlet and outlet of the pipe culvert, stack the second plate on top of the first plate, Align the connecting holes , then insert the bolts into the screw holes from the inside out, Then Install the nut and pre tighten it.Splice the circular ring in a bottom-up order. When assembling the circular ring in a circumferential direction and joining it together, the cross-sectional shape should be measured and fixed with a positioning rod. After all the culvert tubes are bottled, a dedicated wrench can be used to tighten all bolts with a certain torque.
Construction of corrugated steel pipe culverts
Before the construction of corrugated steel pipe culverts, check all the tools and accessory. Check the diameter, length of the corrugated pipe culvert, to make sure all the parts is comply with the corrugated pipe regulations.
Depending on the construction site situation, place the corrugated pipe culverts in right place. From one side to put the first pipe plate, to make the center of the corrugated pipe culvert and longitudinal center line of the foundation parallel.
Back filling
The backfill material of the top and both sides material should be the same within a 2.0m range roadbed filling materials can be selected. To ensure compactness, concrete with a strength grade of C15 can be selected.
When back filling both sides of the pipe culvert, before filling, use red oil first Paint a height mark every 15cm on both sides of the pipe culvert to indicate the filling height When backfilling the top of the culvert pipe, when the filling thickness is within 50cm, It can be compacted by a hand-held vibrating roller, with a filling thickness exceeding 50cm. An 18t roller can be selected for compaction. It should be noted that culvert pipes Heavy vehicles are not allowed to pass until the minimum filling height is reached. End Culverts with retaining walls can be back filled from both ends towards the center, while those without retaining walls ,Culverts can be back filled from the center to both ends
Conclusion
The construction of corrugated pipe culverts on mountainous roads is a complex , and it is a systematic works.
It covers a wide range of content, and if there is a problem in any aspect,It can affect the quality of corrugated pipe culverts, making their function unable to be fully used. To avoid this problem,construction personnel should master the corrugated pipe culvert key construction techniques in order to Provide quality assurance for pipe culverts.