Papp Jr., Recycled Asphalt Pavement as a Base and Subbase
Material: Testing Soil Mixed with Waste or Recycled Materials, ASTM STP 1275, pp.
While the true finesse of Trimble's averaging beams will not be evident until January 2018, when the laying of the wearing course begins, another system from Sitech Gulf has already resulted in a big increase in the productivity over the course of laying the subbase
In MCHW Series 800 (MCHW, Volume 1, SHW, Series 800, 2007), four types of unbound mixtures for subbase
are defined (Type-1, Type-2, Type-3 and Type-4).
The slabs in section 4-0 placed in the morning showed relatively larger elastic moduli and the slabs in section 5-0 showed relatively lower elastic moduli for both the concrete slab and the lean concrete subbase
. In contrast with the results of the AREA method, the cyclic trend of the elastic moduli of the slabs in section 4-0 backcalculated by the MET was very clear.
The best option to improve subbase
drainage and reduce the risk of premature pavement failure in an existing parking lot is to install an underdrain system to allow moisture a point of relief.
"On the other hand, porous and nonporous steel-slag aggregates should never be used in the bases or subbases
without any proper curing that satisfies the limitation specified by ASTM D2940," they write.
As the placement continued, the temperature of the subbase
surface increased due to continuous sun exposure.
For example, a heavily trafficked, rural interstate highway built over a relatively weak subgrade might have a design thickness of 11.1 inches if a 6-inch low-quality, unbound granular subbase
is spread, depth is controlled by holding the shovel handle on top and adding or removing material until the beam lilts the bottom mark.
Not much literature is available on combined use of lime-stabilized soil and brick powder as a subbase
in flexible pavements.
Full scale road trials were constructed on Qatar Steel site to demonstrate the successful use of steel slag in the various road layers of asphalt base and unbound subbase
Updated from a charter 2008 version and available in a free trial, Permeable Design Pro Software v2.0 for permeable interlocking concrete pavement (PICP) generates time-saving cross section drawings with base and subbase
thicknesses, plus CAD drawings illustrating calculated hydrologic and structural requirements from user-designated rainfall events, runoff flows from contiguous surfaces, traffic loads, underdrains and soil subgrade characterizations.