Polyethylene Manholes Superiority Over Concrete Manholes
Absence of sewage leak from polyethylene manholes compared to brick or concrete counterparts with concrete gutter due to concrete disintegration against chemicals and its little vulnerability during the passage of suspended particles in the sewage flow.
Against chemical and sulfated materials in the groundwater, in places such as the south of the country and also during rain, permeation of these chemicals can cause concrete and brick corrosion in concrete and brick manholes
Due to abundant openings in brick manholes and also concrete’s permeability, at the joint of pre-made segments, the inner wall is consistently wet and in addition to forming extra current, the possibility of pests, such as cockroaches and mice, nesting would be high, while such cases are not seen in polyethylene manholes at all.
- During earthquake, especially in Iran, plenty of examinations indicate the demolition of brick manholes, while polyethylene manholes are completely durable and flexible against these shakes and tremors.
The connections of pipes to manholes in brick and concrete manholes have always been problematic and when there is a slight subsidence, this subsidence reaches its maximum amount and with the infiltration of tree roots, the manhole gradually disintegrates. The pipe connection in polyethylene manholes don’t suffer from leakage with change in the angle to 10 degrees.
The formation of sewer gas (Hydrogen Sulfide (H2S)) and humidity produce sulfuric acid on the walls of brick and concrete manholes and demolish the manhole in the course of time. However, this doesn’t affect the walls in polyethylene manholes.