4120.01DESCRIPTION
Uniform mixture of fine and coarse particles of crushed stone, gravel, or a combination of these materials with sand. Crushed recycled materials are to total no more than: • 30% of the shoulder aggregate for new construction. • 50% of the total for existing granular shoulders. 4120.02
GRANULAR MATERIAL.
A.
Granular Surfacing. Furnish material meeting the requirements of Article 4120.04, or when specified in the contract documents, meet the requirements of Article
4120.03, 4120.05, or 4120.06
B.
Granular Shoulders. 1.
Furnish material meeting the requirements of Article 4120.04 or recycled materials. When specified in the contract documents, meet the requirements of Article 4120.05 or 4120.06. For recycled materials, meet the following requirements: • Recycle PCC, RAP, or composite pavements to meet the requirements of Materials I.M. 210. • Crush PCC or composite pavement to meet the requirements for Gradation No. 11 of the Aggregate Gradation Table, Article
4109.02
• Process RAP to pass the 1.5 inch sieve.
2.
The contract documents may allow a Class C gravel and crushed aggregate mixture for granular shoulders meeting the following: • 30% to 50% crushed stone meeting soundness and abrasion requirements of Article 4120.05. Meet the requirements for Gradation No. 10 of the Aggregate Gradation Table, Article 4109.02 with the exception of 8% to 16% passing the No. 200 sieve. • 30% to 50% recycled crushed PCC or composite materials meeting the above requirements for Granular Shoulders. Meet the requirements for Gradation No. 10 of the Aggregate Gradation Table, Article 4109.02 with the exception of 8% to 16% passing the No. 200 sieve. • 30% to 50% RAP processed to pass the 1.5 inch sieve.
CLASS C GRAVEL
Meet the requirements for gradation No. 10 of the Aggregate Gradation Table, Article
and Table 4120.03-1:
4120.06
Granular Surfacing and Granular Shoulder Aggregate
Table 4120.03-1: Coarse Aggregate Quality (Class C Gravel) Coarse Aggregate Quality
Maximum Percent Allowed
Test Method
C Freeze
Shale (+ No. 4 sieve)
Iowa DOT Materials Laboratory Test Method No. 211, Method C Materials I.M. 372
Total of Clay Lumps and Friable Particles, plus % passing No. 200 sieve
Materials I.M.s 368 and 306
Total of Shale, Clay lumps and friable particles, plus % passing. No. 200 sieve
Materials I.M.s 372, 368, and 306
4120.04CLASS A CRUSHED STONE
Meet the requirements for Gradation No. 11 of the Aggregate Gradation Table, Article
and Table 4120.04-1:
Table 4120.04-1: Coarse Aggregate Quality (Class A Crushed Stone) Coarse Aggregate Quality
Maximum Percent Allowed
Abrasion
C Freeze
Clay Lumps and Friable Particles
4.0
Test Method AASHTO T 96 Iowa DOT Materials Laboratory Test Method No. 211, Method C Materials I.M. 368
Note: For Granular Shoulder Aggregate only, the abrasion limit is 50.
4120.05CLASS B CRUSHED STONE
Meet the requirements for Gradation No. 11 of the Aggregate Gradation Table, Article
and Table 4120.05-1:
Table 4120.05-1: Coarse Aggregate Quality (Class B Crushed Stone) Coarse Aggregate Quality
Maximum Percent Allowed
Abrasion
55
C Freeze
Total of Abrasion & C Freeze
65
Clay Lumps and Friable Particles
Test Method AASHTO T 96 Iowa DOT Materials Laboratory Test Method No. 211, Method C
Materials I.M. 368
4120.06CLASS D CRUSHED STONE
Refer to the contract documents for gradation and quality requirements.
Crushed Stone Base Material
4122.01
4120.07AGGREGATE FOR PAVED SHOULDER FILLETS
Crushed stone or recycled materials meeting the requirements for Gradation No. 11 of the Aggregate Gradation Table, Article 4109.02, and meeting the quality requirement of Article 4120.04. For recycled materials, meet the requirements of Article 4120.02, B.