The Average Least Dimension (ALD) is a crucial concept in pavement engineering, specifically related to aggregate size and shape. It's defined as the arithmetic mean of the smallest perpendicular distances measured between parallel plates for aggregate particles, essentially the average of the smallest dimension of individual aggregate particles in a sample. This value helps determine the starting spread rate for seal coat operations, as it relates to the tendency of particles to lie with their least dimension vertical. 

The Average Least Dimension (ALD) is a crucial concept in pavement engineering, specifically related to aggregate size and shape. It's defined as the arithmetic mean of the smallest perpendicular distances measured between parallel plates for aggregate particles, essentially the average of the smallest dimension of individual aggregate particles in a sample. This value helps determine the starting spread rate for seal coat operations, as it relates to the tendency of particles to lie with their least dimension vertical. 

• As per IS Standard.

Average Least Dimension (ALD) device complete with ALD box - adjustable spacer – fine aggregates 2-9 mm, 1 x spacer set-fine aggregates spare case, spacer set extension 10-18 mm.

Average Least Dimension (ALD) device complete with ALD box - adjustable spacer – fine aggregates 2-9 mm, 1 x spacer set-fine aggregates spare case, spacer set extension 10-18 mm.