The last small series introduced some common stones used in backfill foundation of New Zealand to you, and this issue introduced different types of excavations in New Zealand.
So just to give you a little bit of an overview of the soil layer in New Zealand,First of all, the surface layer will have a plant layer about 100-200mm thick.And then you see that the black soil layer that we call Topsoil is about 100 — 500mm thick.And then down here is the loess layer which is what we usually call good Clay.The depth of the layers varies from region to region, and some areas even have layers of stone.
According to New Zealand regulations NZS3604, the geological strength of light wood structure buildings must exceed 300kpa.Because the geological strength of the plant layer and the black soil layer is not enough, the black soil layer must be removed before making the foundation, or a certain amount of stones must be backfilled to achieve the geological strength of building.
What kind of soil would you have when you officially opened it?And what types of soil do the reclaimers classify?
T2: Clean & DryTopsoil or Clay
Clean pure black soil, or pure loess
T3: All type mixed soil
plants/stones/cement blocks/wet soil less than 10% of the mixture, and no waste.This type of soil is usually the surface of a house after the old division, there will be a small amount of grass, broken stone, and after rain slightly moist soil.The price is high because it is difficult to classify all kinds of mixed with excavators
T4: Clean Concrete
Solid cement or stone less than 500mm in diameter (for those exceeding the specification, T3 will be charged)
T5: Vegetation without Dirt/ stumps /Rubbish plants
Including tree trunks, plant layers of grass, plants, etc., which do not contain (soil/roots/garbage),The difference between T5 and T3 is that the plant content of T3 must be less than 10% of the total vehicle.If it exceeds 10%, it will be charged according to T5. Since plants are difficult to deal with, T5 will be more expensive than T3.
T6:Rubbish without Dirt!
(plants/stones/cement blocks/wet soil) anything above 10% is garbage, which is the most expensive because it is the most difficult to dispose of.
T7: Slush Soil
Soil with a moisture content of more than 30% (usually more in winter and rainy seasons) is difficult to treat and expensive due to its high moisture content.