Gradation Bands

Sieve analysis control points for Superpave and Marshall mix designs per AASHTO M323 / ASTM D3515

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Control Points & Restricted Zone

Upper/lower limits for each sieve to ensure proper aggregate structure

Sieve Size	Control Point	Min % Passing	Max % Passing	Notes
19.0 mm (3/4")	—	100	100	100% passing
12.5 mm (1/2")	Control	90	100	Primary control sieve
9.5 mm (3/8")	Restricted	—	90	Avoid restricted zone
4.75 mm (No. 4)	—	—	90	Max 90% passing
2.36 mm (No. 8)	Control	32	67	Key workability control
1.18 mm (No. 16)	—	—	—	—
0.600 mm (No. 30)	—	—	—	—
0.300 mm (No. 50)	—	—	—	—
0.150 mm (No. 100)	—	—	—	—
0.075 mm (No. 200)	Control	2	10	Dust content control

Sieve Size	Control Point	Min % Passing	Max % Passing	Notes
25.0 mm (1")	—	100	100	100% passing
19.0 mm (3/4")	Control	90	100	Primary control sieve
12.5 mm (1/2")	Restricted	—	90	Avoid restricted zone
9.5 mm (3/8")	—	—	90	Max 90% passing
4.75 mm (No. 4)	Control	28	58	Key workability control
2.36 mm (No. 8)	—	—	—	—
1.18 mm (No. 16)	—	—	—	—
0.600 mm (No. 30)	—	—	—	—
0.300 mm (No. 50)	—	—	—	—
0.150 mm (No. 100)	—	—	—	—
0.075 mm (No. 200)	Control	1	7	Dust content control

Sieve Size	Control Point	Min % Passing	Max % Passing	Notes
19.0 mm (3/4")	—	100	100	100% passing
12.5 mm (1/2")	Control	90	100	Primary control sieve
9.5 mm (3/8")	Controlled	—	90	Max 90% passing
4.75 mm (No. 4)	Control	44	74	Key control point
2.36 mm (No. 8)	—	28	58	—
1.18 mm (No. 16)	—	—	—	—
0.600 mm (No. 30)	—	—	—	—
0.300 mm (No. 50)	—	—	—	—
0.150 mm (No. 100)	—	—	—	—
0.075 mm (No. 200)	Control	2	8	Dust content control

Sieve Size	Control Point	Min % Passing	Max % Passing	Notes
25.0 mm (1")	—	100	100	100% passing
19.0 mm (3/4")	Control	90	100	Primary control sieve
12.5 mm (1/2")	Controlled	—	90	Max 90% passing
9.5 mm (3/8")	—	—	—	—
4.75 mm (No. 4)	Control	35	65	Key control point
2.36 mm (No. 8)	—	23	52	—
1.18 mm (No. 16)	—	—	—	—
0.600 mm (No. 30)	—	—	—	—
0.300 mm (No. 50)	—	—	—	—
0.150 mm (No. 100)	—	—	—	—
0.075 mm (No. 200)	Control	2	8	Dust content control

Gradation Curve Visualization (0.45 Power Chart)

📈 0.45 Power Gradation Chart — Plot blend gradation against control points and restricted zone

Restricted Zone Avoidance

Restricted zone: Sieve sizes between control points where gradation should not pass through
Superpave 12.5mm: Avoid passing through 9.5mm restricted zone (max 90% passing)
Superpave 19mm: Avoid passing through 12.5mm restricted zone (max 90% passing)
Marshall: Controlled points act similarly — max 90% at adjacent sieve
Passing through restricted zone → tender mix, compaction problems
Use 0.45 power chart to visualize and verify compliance
Blend 3+ aggregate sources to achieve target gradation curve