SECTION 401
2.7.2. The general composition limits given in Table 411-1 indicate target value ranges of mixtures permissible under
Section 411. The job mix formula shall lie within the target value ranges indicated for the particular type of hot asphalt mix.
2.8 General - Bridge pavement base course shail be 3/8” wearing course.
2.9 General - Non-modified asphalt binder shall contain silicone additive with the concentration being 3 parts per million plus
or minus 1 part per million of silicone to asphalt binder, unless otherwise directed. Silicone additive shall be in liquid form and
have a viscosity of 1,000 centipoises (1 Pas) at 77 °F. Asphalt binder containing silicone shall meet the requirements of 401.2.2
2.10 Allowed Recycled Materials — General.
2.10.1 Reclaimed asphalt pavement (RAP) may be used in the production of hot mix asphalt. The allowed dust to asphalt
ratio shall be as identified in AASHTO M 323. The maximum allowable total reused “ asphalt” binder (TRB) in HMA mixes
shall be 1.5%. Any changes in the combination of recycled materials shall require a new mix design unless otherwise approved
by the Bureau of Materials & Research.
2.10.2 Reclaimed Asphalt Pavement (RAP).
RAP shall consist of recycled asphalt pavement and shall be processed by crushing, cold milling, or other approved sizing
techniques approved by the Bureau of Materials and Research to meet the required gradation specifications. The mixture of RAP
and new aggregate shall meet the requirements specified in Table 401-1 for aggregate gradation. The RAP shall be tested every
1,000 tons for gradation and asphalt binder content as a stockpile is being built. These test results shall remain on file by the
Contactor until such time as the entire RAP stockpile has been utilized.
2.10.2.1 The PG grade of added asphalt shall be as specified by the Bureau of Materials and Research. The aggregate
component of the RAP shall meet the requirements of 401.2.1. The bitumen component of the RAP shall be asphalt cement and
shall be free of significant contents of solvents, tars, and other volatile organic compounds or foreign substances that will make
the RAP unacceptable for recycling as determined by the Bureau of Materials and Research.
2,10.2.2 RAP materials may be rejected if deemed unsuitable for any reason or require an increase or decrease in the mix
asphait content. The Contractor shall submit representative samples, and gradation and asphalt cement content test results of the
RAP to be incorporated into the Recycled Mixture for approval by the Bureau of Materials and Research at least 30 calendar
days prior to the start of paving.
2.10.3 For afl designs containing TRB in an amount greater than 1% of the total mix:
(a) RAP stockpiles shall be covered by a roof.
(b) Prior to the start of production, the composite RAP and virgin binder shall be tested by the Contractor to
determine the appropriate grade of virgin binder to be added.
(c) Only allowed in a drum mixer.
(d) Only allowed for binder & base courses.
(ec) Test RAP for gradation & AC% every 1000 tons.
(f) Run split samples at start of production and every 10k tons thereafter for composite binder testing.
2,11 Asphalt Modifiers.
General. The generic type of each asphalt binder admixture, modifier and/or additive shall be identified on the certificate
of analysis, which shall be furnished by the manufacturer for each load of asphalt delivered. Modifiers shall be pre-blended with
the asphalt binder.
2.41.1 Asphalt binder modification to produce high-strength mix shall utilize either a styrene-butadiene or styrene-butadiene-
styrene polymer to achieve the specified performance grade of asphalt. The Section 401 contract Special Provision specifying
the asphalt binder grade shall also identify the AASHTO test method by which the binder grade shall be determined. The
modified binder shall be pre-blended, storage-stable and homogencous.
2.11.2 The use of Warm Mix Technologies is permitted in mix production. Qualified technologies are listed on the Qualified
Warm Mix Asphalt (WMA) Technologies List.
2.12 Pavement Joint Adhesive.
Pavement Joint Adhesive shall be a product that is listed on the Qualified Products List.
2.12.1 Joint adhesive shall meet the following requirements:
2016 NHDOT
Go To= TOC Division 100 Division206 Division 300 Division 400 Standard
Division S00 Division 600 Division 700 Specifications
