Category:413 Surface Treatments and Preventive Maintenance

District Procedure

When the District receives a proposed trial mix formula, as required by the Standard Specifications, the mixture properties, components and proportions should be checked to ensure compliance with Specifications and that they are approved for the intended use. It may be necessary for the District to advise the contractor to make changes in the proposed mixture in order to comply with Department policies. A QC plan in accordance with Field Section 1001 covering each aggregate fraction should be on file in the District Office or received with the JMF. The target gradations shown on the QC plan and JMF must match. When the District is satisfied that the proposed mixture is acceptable, a copy of the JMF and the contractor's letter shall be submitted to the Materials Field Office, accompanied by a letter of transmittal with comments, any corrections made and recommendations. The transmittal letter shall contain the following information:

Project information – Job Number, Route, County, Contract Number.

Mixture Type

Grade and Source of Asphalt Binder

Letting Date

Proposed Work – Job Location and Length

Average Daily Traffic (ADT)

Mix Use – Mainline, Shoulders, Outer Roads, etc.

Quantity of Mix

Field Office Procedure

The Materials Field Office is charged with the responsibility of processing the mix formula. General procedures for processing a micro-surfacing mix formula are as follows:

a. A letter from a District requesting a mix with a copy of the contractor's JMF and letter is received.

b. Contract specifications for the project are checked for necessary items.

c. Grade of asphalt as well as the refinery to be used and the percent asphalt recommended are reviewed.

d. Gradations of the aggregates are checked for specification compliance.

e. All calculations on the proposed JMF are checked.

f. For verification, a trial may be prepared and submitted to the Laboratory.

413.1.2.2 Scrub Seal

District Procedure

District procedures are identical to those in micro-surfacing above.

413.1.2.3 Ultra-Thin Bonded Asphalt Wearing Surface

Mix Design Procedure

In order for an Ultrathin Bonded Asphalt Wearing Surface mix formula to be approved, the contractor’s proposed job mix formula (JMF) shall be submitted as required in Standard Specification Sec 413.30.2.5. The time for approval starts when the completed design is delivered to the District. This time restarts when the District receives information omitted from the original JMF or corrected by the contractor. Review/verification time includes District and Central Office processing, therefore, each mix should be processed as soon as possible. Trial mix samples shall be obtained and submitted to the Central Laboratory in accordance with Field Section 1001. When possible, the JMF and correspondence should be transmitted electronically. The Materials Field Office e-mail address is MFO.

District Procedure

District procedures are identical to those in micro-surfacing above.

Field Office Procedure

The Materials Field Office is charged with the responsibility of processing the mix formula. General procedures for processing an ultra thin bonded asphalt wearing surface mix formula are as follows:

a. A letter from a District requesting a mix with a copy of the contractor's JMF and letter is received.

b. Contract specifications for the project are checked for necessary items.

c. Grade of asphalt as well as the refinery to be used and the percent asphalt recommended are reviewed.

d. Gradations of the aggregates are checked for specification compliance and compared with the gradations determined by the Laboratory.

e. All calculations on the proposed JMF are checked.

f. For verification, a trial mix is prepared and submitted to the Laboratory.

g. When Central Laboratory tests are completed, the results are compared to the contractor’s and against the specifications. If the mixes tested cannot be used, the mixture will be rejected.

413.1.2.4 Bituminous Fog Sealing

District Procedure

District procedures are identical to those in micro-surfacing above.

413.1.2.5 Bituminous Pavement Crack Sealing

District Procedure

District procedures shall be in accordance with the applicable sections of Materials Manual Field Section 1057.

413.1.2.6 Portland Cement Concrete Pavement Joint/Crack Sealing

District Procedure

District procedures shall be in accordance with the applicable sections of Materials Manual Field Section 1057.

413.1.2.7 Bituminous Pavement Crack Filling

District Procedure

District procedures shall be in accordance with the applicable sections of Materials Manual Field Sections 1015 and 1057.

413.1.2.8 Portland Cement Concrete Pavement Crack Filling

District Procedure

District procedures shall be in accordance with the applicable sections of Field Section 1057.

413.1.3 Report

413.1.3.1 Micro-Surfacing

A letter of transmittal will accompany the approved mixture to the district Operations Engineer with distribution as follows:

The letter of transmittal and the approved mixture will be sent by electronic mail to the individuals listed above.

A copy of the approved formula accompanied by a letter of transmittal from the District Operations Engineer is to be forwarded to the contractor.

413.1.3.2 Ultra-Thin Bonded Asphalt Wearing Surface

Reporting procedures are the same as shown for micro-surfacing.

==413.2

413.1 SCOPE. To establish procedures for Laboratory testing and reporting of Micro-Surfacing trial mixtures, Scrub Seal mixtures, Ultrathin Bonded Wearing Asphalt Surface mixtures, Bituminous Fog Seals, Bituminous Pavement Crack Sealing material, Portland Cement Concrete Pavement Joint/Crack Sealing material, Bituminous Pavement Crack Filling material and Portland Cement Concrete Pavement Crack Filling material.

413.2 PROCEDURE.

413.2.1 Micro-Surfacing. Micro-Surfacing mix properties shall be determined, when required, in accordance with the applicable International Slurry Surfacing Association (ISSA) Technical Bulletins.

413.2.2 Scrub Seal – This section left blank intentionally.

413.2.3 Ultrathin Bonded Asphalt Wearing Surface. Test results and calculations required for Ultrathin bonded asphalt wearing surface trial mixtures are as shown in paragraphs 413.2.3.1 through 413.2.3.11. Test results and calculations shall be recorded through SiteManager.

413.2.3.1 The Los Angeles Abrasion value of the aggregate shall be determined, when required, in accordance with AASHTO T 96. Los Angeles Abrasion shall be determined on an individual ledge basis.

413.2.3.2 Sodium sulfate soundness of the aggregate shall be determined, when required, in accordance with AASHTO T 104. Soundness shall be determined on an individual ledge basis.

413.2.3.3 Flat and Elongated Particles in Coarse Aggregate, 3:1, shall be determined in accordance with ASTM D 4791. Flat and Elongated Particles shall be determined on the aggregate blend.

413.2.3.4 Percentage of Fractured Particles in Coarse Aggregate shall be determined in accordance with ASTM D 5821. Percentage of Fractured Particles shall be determined on the aggregate blend.

413.2.3.5 Micro-Deval shall be determined in accordance with AASHTO TP 58. Micro-Deval shall be determined on an individual ledge basis.

413.2.3.6 Plastic Fines in Graded Aggregates and Soils by Use of the Sand Equivalent Test shall be determined in accordance with AASHTO T 176. The Sand Equivalent shall be determined on the aggregate blend.

413.2.3.7 Methylene Blue shall be determined in accordance with AASHTO TP 57. Methylene Blue shall be determined on the aggregate blend.

413.2.3.8 The Uncompacted Void Content shall be determined in accordance with AASHTO T 304. The Uncompacted Void Content shall be determined on the aggregate blend.

413.2.3.9 The Acid Insoluble Residue (AIR), when required, shall be determined in accordance with MoDOT Test Method TM 76. AIR is to be determined on the aggregate blend.

413.2.3.10 Drain Down of the loose mixture shall be determined in accordance with AASHTO T 305.

413.2.3.11 The Tensile Strength Ratio (TSR) shall be determined in accordance with AASHTO T 283, with the following modifications:

(a) Section 6.2 - Specimens 4 inches (100 mm) in diameter and 2.5 inches (63.5 mm) thick shall be used.

(b) Section 9.4 – Calculate the volumetric bulk specific gravity Gmb as follows:

where:

W = Weight – air dry (pounds) D = Diameter of specimen (inches) h = Height of specimen (inches)

(c) Section 10.3.2 - Prior to placing the specimen in the vacuum vessel, a sheet of plastic film shall be placed on the balance to ensure any water draining from the specimen is not lost, and the balance shall be zeroed. The SSD mass of the specimen shall be determined within two minutes of removing the sample from the vacuum vessel.

(d) Section 10.3.7 - If the degree of saturation is acceptable, the specimen shall be wrapped with the plastic film and placed in a plastic bag containing 0.003 gallon (10 mL) of water. Within two minutes of placing the specimen in the bag, the specimen shall be placed in the freezer. All moisture draining from the specimen during the process shall be collected by the plastic film and shall not be discarded.

413.2.4 Bituminous Fog Sealing – This section left blank intentionally.

413.2.5 Bituminous Pavement Crack Sealing. The sealing material shall be tested in accordance with AASHTO M 301 with the following modifications:

(a) The sealant shall be capable of being reheated to pouring temperatures at least once after the initial heating, while retaining the sealant’s physical characteristics.

(b) Penetration at 77 F (25 C), 150 grams, 5 seconds, shall be no less than 50 or greater than 90.

(c) When tested at 77 F (25 C), the resilience recovery shall be a minimum of 50 percent.

(d) The sealant shall meet all physical requirements after prolonged heating for six hours with constant mixing in a laboratory melter at the recommended field pouring temperature, complete cool down, and reheating to the recommended pouring temperature.

413.2.6 Portland Cement Concrete Pavement Joint/Crack Sealing. The sealing material shall be tested in accordance with the applicable sections of Laboratory Section 1057.

413.2.7 Bituminous Pavement Crack Filling. The sealing material shall be tested in accordance with the applicable sections of Laboratory Sections 1015 and 1057.

413.2.8 Portland Cement Concrete Pavement Crack Filling. The sealing material shall be tested in accordance with the applicable sections of Laboratory Sections 413.2.5 and 1057.