Precast Manhole Material Quantity

a — inner length (cm)

b — inner width (cm)

c — bottom slab length (cm)

d — bottom slab width (cm)

m — precast slab length (cm)

n — precast slab width (cm)

h — inner height (cm)

k — precast slab thickness (cm)

r — bottom slab thickness (cm)

t — wall thickness (cm)

Blinding gap (cm)

Blinding thickness (cm)