Slurry seal

The slurry seal with the evacuation line is designed to handle/evacuate suspended solids, crystals, sediment, and dirt in the pumpage. The seal s springs are located out of the fluid. The o-rings move and rub across a clean surface as the faces wear. The o-rings are placed away from the heat generated by the faces. 

D 3910 D 4070 Practice for Design, Testing, and Construction of Slurry Seal Specification for Adhesive Lubricant for Installation of Preformed Elastomeric Bridge Compression Seals in Concrete Structures... 

Diable AS. [Kao Cotp. SA] Amine-based slurry seal and emulsifier. 

Slurry seal 20 5.2x10-5 5.2x10-5 1.2x10-5 3.9X10 5... 

The grades and required properties of cationic emulsions according to ASTM D 2397 (2012) are presented in Table 3.15. It should be noted that the specification includes a grade of cationic emulsion, quick setting , exclusively used in slurry seal systems. 

Cold asphalts are divided into two general categories, those for surface, binder, base or subbase courses, or for pothole filling known as cold asphalt mixtures (CAM), and those for slurry surfacing (SS), known as slurry seals (SSI) or micro-surfacings (MS). 

When slurry surfacing is made of small-sized aggregates and the bituminous emulsion is not modified, it is called slurry seal. 

Slurry seals and in particular micro-surfacing, apart from being laid faster than any other bituminous mixture, have the following advantages and properties ... 

Cold asphalts for slurry surfacing are specified by international standards, specifications and guidelines, such as CEN EN 12273 (2008) for slurry surfacing, ASTM D 3910 (2011) or International Slurry Seal Association (ISSA) A105 (2010) for slurry seals and ASTM D 6372 (2010) or ISSA A143 (2010) for micro-surfacing. 

With respect to slurry seals, the aggregate requirements by the Asphalt Institute and ISSA are as follows Los Angeles abrasion loss, grading C or D, <35%, sand equivalent 45 (Asphalt Institute MS-19 2008 ISSA A105 2010). ISSA also has a requirement for soundness of aggregate, which is the same as for aggregates for micro-surfacing. 

Mix design procedure for slurry surfacing is provided by ASTM D 3910 (2011) for slurry seal and ASTM D 6372 (2010) for micro-surfacing. 

Table 6.4 Types of slurry seals and indicative ranges of bitumen content and application rates of dry aggregates...

For slurry seal, when the pavement surface is in relative good condition and surface texture does not change significantly, according to ISSAAIOS (2010). 

The mix design procedure for slurry seal according to ASTM D 3910 (2011) requires the execution of the following tests (a) consistency test, (b) set time test, (c) cure test and (d) wet track abrasion test, all described in ASTM D 3910 (2011). 

Properly designed slurry should be set at the end of 12 h. For the quick-setting slurry seal, a much shorter set time is considered acceptable. 

The cure time test is used to determine initial cohesion of slurry mat and resistance to traffic. Total cure of a slurry seal mat is obtained when complete cohesion between bitumen-coated aggregate particles occurs. 

The wet track abrasion test covers measurement of the wearing qualities of slurry seal under wet abrasion conditions. 

A slurry seal mix should not show a loss of more than 807 g/m. ... 

Both set times are determined by employing the cohesion testing device, used to measure cure time of slurry seal, measuring the torque of a micro-surfacing mixture as it coalesces and develops cohesive strength. The amount of torque developed plotted over time shows how the mixture is developing resistance to movement. 

The wet track abrasion test is used to determine the minimum bitumen content and the mixture s resistance to stripping. The test is the same as the one used in mix design for slurry seals, briefly described in the above paragraph. 

The determination of cohesion of the mix is carried out according to CEN EN 12274-4 (2003). The test method measures the development of cohesive strength and defines the time when the slurry seal or micro-surfacing can accept traffic. The test is similar to the cohesion test described in ASTM D 6372 (2010), a brief description of which is given in Section 6.8.3.2 (cohesion test). 

ASTM D 3910. 2011. Standard practices for design, testing, and construction of slurry seal. West Conshohocken, PA ASTM International. 

Indonesian MPW. 1990. Paving Specifications Utilizing Bitumen Emulsions Section 6.10 - Dense-Graded Emulsion Mixtures. Directorate General of Highways. Jakarta Ministry of Public Works. ISSA A105. 2010. Recommended performance guidelines, for emulsified asphalt slurry seal. Annapolis, MD International Slurry Seal Association. 

ISSA A143. 2010. Recommended performance guidelines, for micro-surfacing. Annapolis, MD International Slurry Seal Association. 

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