Precast reinforced concrete box culvert is made of concrete which is automatically mixed and batched .Designed length is short , generally, it’s 1.0m to 3.0m for one joint which is joint by soft rubber ring .
The connection end is laying on soil foundation directly without concrete cushion thus save the cost. But because the construction conditions are very bad , safe operation is very important. precast reinforced concrete box culverts is produced in workshop with high automatic euqipment, the labor working strength is much lower and almost no any dust and noise. precast reinforced concrete box culvert mold casting in place with closed working place because if there are too many people with disorder, it may cause safety problems. When construction starts to dig ditch, earth can’t covered for long time. If there is underground water is out or long time raining, there is very high risk for safety.