Best practices for pervious concrete mix design and laboratory tests

Abstract

Pervious concrete may be used for stormwater management since it allows the water to pass through its interconnected macropores into stormwater systems or soils below. However, there is a need for additional standards related to pervious concrete prior to its widespread use, and there are many aspects related to mix design for desired properties, compaction methods, and test procedures that are not yet completely understood. These variables may significantly affect the functional and mechanical performance of the material. In this paper, mix designs and test specimen preparation techniques were evaluated. The IBRACON method for mixture design was used to obtain the mixture proportions and the calculated density for the desired porosity of 25%. In addition, two different types of specimens (cast or cored) and compaction methods (roller or Proctor hammer compacted) were performed. The density of each specimen was controlled to obtain the same calculated density. Several tests were conducted to compare the following variables: density, porosity, surface infiltration rate, permeability and compressive strength. Additionally, the effects of mortar capping versus neoprene-rubber caps on compressive strength measurements of pervious concrete were evaluated. The experimental results showed that cast specimens have more consistent results than cores. The design method studied with strict control of density was efficient to obtain the desired porosity mainly for cast specimens. The roller leads to a more compacted top surface resulting in a decrease in the infiltration rate and permeability of the cores. The mortar capping method is more consistent than the other.

Investigation of the Effects of Compaction on Compressive Strength and Porosity Characteristics of Pervious Concrete

“…Results indicated that compressive strength increased with fresh density, whereas porosity decreased simultaneously, whatever the number of compaction layers or blow pattern. Both parameters exhibited a clear linear dependence on fresh density, as pointed out in the literature (40,41). With the increase in A/C ratio, compressive strength and fresh density reduced for all mixes.…”

Characterization of pervious concrete focusing on non-destructive testing

“…However, for some researchers [12,[15][16][17][18][19], the permeability test may be performed with constant-head permeameter for specimens with high porosity and high permeability. On the other hand, other authors [20][21][22][23] perform the test using falling-head permeameter, regardless of the porosity level of the specimens. In this sense, mix design philosophies of pervious concrete are limited.…”

A review of factors influencing performance of pervious concrete

“…Connectivity of pores can be negatively affected by the compaction method and energy due to its effect in the orientation and packing of ingredients and, hence, restriction of compaction is essential [29]. Impulsive compaction methods such as proctor hammer [17,28,[67][68][69] or Marshall hammer [41,66] are quite often used to compact porous concrete specimens for testing purposes. In the case of pavement application, pervious concrete is compacted using hand steel rollers with low compaction energy [66].…”