Journal of Environmental Treatment Techniques  
2020, Volume 8, Issue 1, Pages: 429-436  
J. Environ. Treat. Tech.  
ISSN: 2309-1185  
Journal web link: http://www.jett.dormaj.com  
Reducing Urban Runoff Pollution Using Porous  
Concrete Containing Mineral Adsorbents  
1
*
2
3
3
Ehsan Teymouri , Sayed-Farhad Mousavi , Hojat Karami , Saeed Farzin and Maryam  
Hosseini Kheirabad4  
1
Graduated MSc. Faculty of Civil Engineering, Semnan University, Semnan, Iran  
2
Professor, Faculty of Civil Engineering, Semnan University, Semnan, Iran  
3
Assistant Professor, Faculty of Civil Engineering, Semnan University, Semnan, Iran  
4
MSc. Student, Faculty of Civil Engineering, Payame noor University, P.O. Box: 19395-3697, Tehran, Iran  
Received: 20/09/2019  
Accepted: 12/12/2019  
Published: 20/02/2020  
Abstract  
Porous concrete has been used in sidewalks and surface pavements since the last decade for management of urban runoffs.  
Porous concrete is considered valuable for its hydraulic conductivity, adsorption capacity for pollutants, reduction of turbidity and  
contaminants, especially heavy metals. The present research examines the effect of adding minerals such as zeolite (Z), perlite (Pe),  
pumice (Pu) and LECA (L), which are able to adsorb pollutants, at different percentages (0, 5,10 and 15%) and fine-grains (0, 10  
and 20%) to porous concrete blocks to evaluate its mechanical characteristics such as compressive strength, permeability and  
porosity and the ability to improve runoff quality (EC, TDS, NaCl, COD, BOD and turbidity). Results showed that adding fine-  
grains improved runoff quality and enhanced compressive strength, but led to lower permeability and porosity. All adsorbents  
enhanced the quality of runoff and the increase was prominent at higher percentages of additives. Porous concrete had little effect  
on reducing EC, TDS and NaCl contents. The best results belonged to samples containing zeolite and LECA. The L15-0, Z15-10  
and L15-20 treatments (containing 0, 10 and 20% fine-grains and 15% adsorbent) had the highest pollution reduction and improved  
the TSS (75.8, 79.1 and 84.6%), COD (87.1, 82.6 and 89.3%) and BOD (88.1, 87.3 and 90.7%).  
Keywords: Porous Concrete; Zeolite; Perlite; Pumice; LECA; Mechanical characteristics; Runoff quality  
Introduction1  
includes interconnected pores, because of little amount of  
1
fine particles, which allow quick passage of water. The  
porosity of this concrete is from 11 to 35 percent, its  
permeability coefficient is between 1.4 and 12.3 mm/s, and  
its compressive strength is variable ranging from 3.5 to 28  
MPa [3, 4, 5]. Kevern et al. reported that aggregates with  
high level of adsorption or low specific gravity produced a  
pervious concrete with low freeze–thaw permanence. In this  
study, permeability of pervious concrete has been partially  
decreased by addition of sand. In contrast to round  
aggregates, angular aggregates were found to produce more  
actual porosities compared to the intended design porosities  
Nowadays, achieving new water resources is of great  
importance for the increasing population, water pollution  
problems and rising living standards. Urban runoffs can be  
fitted as an important source of fresh water in developing  
countries which do not use water optimally and has too  
many water-related problems [1]. In addition, runoffs on  
urban streets, roads and parking lots, cause organic and non-  
organic substances such as oils, salts, dirt and chemicals to  
be washed away. This can be considered as a runoff pollution  
problem [2].  
Considering the necessity of using runoffs for recharging  
groundwater and maintaining the environmental balance, the  
use of light-weight porous pavements in urban areas is of  
particular importance in different countries. This method can  
also be effective in improving the water quality, by removing  
some of the runoff contaminants, which influences the  
underlying soil layers. Porous concrete (Fig. 1) refers to a  
mixture of Portland cement, coarse-grained particles,  
with/without fine-grains, additives and water, with zero  
slump and open granularity. Porous concrete structure  
[6]. Ćosić et al. studied the influence of aggregate type and  
size on the properties of porous concrete in five different  
concrete mixtures which the aggregates were dolomite or  
steel slag and their diameter was in the range of 4-8 mm to  
8
-16 mm. Results showed that porosity is the main parameter  
for estimating porous concrete efficiency which was affected  
more by the aggregate type than the size [7]. According to  
the Federal Highway Administration, recycled concrete  
aggregates (RCA) is mainly used for road base. Currently,  
only 11 states allow the use of RCA as an aggregate for their  
Corresponding author: Ehsan Teymouri, Graduated MSc.  
Faculty of Civil Engineering, Semnan University, Semnan,  
Iran. E-mail: teymuri.e91@gmail.com, Cellphone: (+98)  
9156906585.  
4
29  
Journal of Environmental Treatment Techniques  
2020, Volume 8, Issue 1, Pages: 429-436  
new concrete projects [8]. Yap et al. showed that using  
recycled coarse aggregates (RCA) decreased compressive  
strength of the porous concrete [9].  
samples, 85, 43 and 76% for samples containing vermiculite  
and 78, 45 and 84% for samples containing quartz,  
respectively [22].  
Using porous concrete in large cities and developed  
countries is a proper method to reduce runoff and prevent  
urban stormwater events. Adding inexpensive minerals to  
porous concrete that has a low specific weight and the ability  
to adsorb contamination, can reduce the volume and improve  
the quality of runoff. In the present study, in addition to  
adding 0, 10 and 20% fine-grains, different percentages of  
mineral adsorbents such as zeolite, perlite, pumice and  
LECA were added to the mixing design. Mechanical  
characteristics of porous concrete such as compressive  
strength, permeability coefficient and porosity, which are  
important factors in the urban roads, were investigated.  
Using the results of mechanical characteristics for each  
percentage of fine grains, 3 samples that had better  
performance in terms of compressive strength were selected  
for quality tests. The COD, BOD, TSS, EC parameters,  
percentage of NaCl and turbidity of selected samples were  
calculated.  
Figure 1: Blocks of porous concrete  
It is important to use filters to improve water quality by  
replacing appropriate materials that can reduce water  
pollution. Some minerals such as zeolite, fly ash, iron slag,  
perlite, LECA, pumice, vermiculite, silica and quartz have  
been used in previous studies to reduce contamination in  
addition to the cost-effective adsorption of contaminants [10,  
2 Material and Methods  
1.2 Concrete and mixing design  
To prepare the mixing design for porous concrete, ACI  
211.3R standard was used to determine the mixing ratios of  
zero-slump concrete [23]. The aggregate and cement values  
were selected to be 1400 and 330 kg/m3, respectively. In  
order to increase the strength of concrete against sulfate  
environments, type 5 cement was used. The water to cement  
ratio was fixed to 0.38 for all samples. Four different  
percentages of the zeolite, perlite, pumice and LECA  
adsorbents (0, 5, 10 and 15% w/w), with 0.6 to 1.2 mm  
average diameter, and three different percentages of fine-  
grains (0, 10, 20) (0, 140 and 280 kg/m3, respectively) with  
size of 2.36 to 4.75 mm, were tested. Figure 2 shows the four  
adsorbents. Figure 3 presents granulometric curves of the  
aggregates and additives. For each sample, three replicates  
were considered to ensure the desired accuracy. The  
adsorbents were saturated before mixing. Chemical  
characteristics of the adsorbents are shown in Table 1. Each  
mixing design was encoded using type of adsorbent in it.  
Letter C is used for control sample, and letters Z, Pe, Pu and  
L are used for samples containing Zeolite, Perlite, Pumice  
and LECA, respectively. The percentage of adsorbents and  
fine-grains is mentioned after the sample’s letter. The first  
number after the letter is percentage of the adsorbent and the  
second number is percentage of the fine grains. For example,  
Z15-10 is porous concrete sample containing 15% zeolite  
and 10% fine-grains.  
1
1, 12, 13]. Using these mineral adsorbents in porous  
concrete, that is applicable to urban roads, is important  
because in addition to preventing the urban storm-runoff,  
they can have positive effects on the improvement of runoff  
quality.  
Tsai et al. used silica to eliminate color from aqueous  
solution [14]. Al-Anber found that bentonite and quartz  
could remove Fe(II) from wastewater [15]. Körlü et al. used  
waste pumice stones to reduce the BOD and COD  
concentration [16]. Verbinnen et al. indicated that perlite-  
supported magnetite is suitable for treating real wastewaters  
by eliminating several oxyanions simultaneously from the  
considered industrial wastewater [17].  
Zhang et al. showed that porous concrete containing  
pumice was able to reduce COD and BOD up to 60% [18].  
Abedi Kupai et al. succeeded in reducing COD, turbidity,  
TSS and lead (Pb) concentration by adding iron slag to  
porous concrete and using sand filter. Contaminants  
concentrations were measured before and after passing the  
samples through the filter. Results showed that COD,  
turbidity, lead (2 mg/l), lead (5 mg/l) and TSS were  
decreased by 11, 38, 44, 42 and 53% and for samples  
containing iron slag these parameters were decreased by 43,  
9
1, 91, 95 and 70%, respectively [19].  
Ong et al. used fly-ash, iron-slag, and limestone powder  
1.2 Porosity test  
in porous concrete to improve urban runoff quality [20].  
Shabalala et al. eliminated some of the heavy metals from  
aqueous solution using porous concrete containing fly-ash  
Porosity was measured in cubic samples (10×10×10 cm)  
using the ASTM C1754 standard [24]. Samples were placed  
in a 105 °C oven for 24 hours. Then, the samples were  
weighed to get their dry weight. Then, they were immersed  
in water and their buoyant weight was measured by an  
Archimedes scale. Porosity of each sample was calculated  
by the following equation:  
[21]. Azad et al. by using vermiculite and quartz in porous  
concrete, managed to reduce TSS, COD and turbidity.  
Results showed that by adding 30% adsorbents to porous  
concrete, the quality parameters such as TSS, COD and  
turbidity were reduced by 45, 14 and 54% for control  
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30  
Journal of Environmental Treatment Techniques  
2020, Volume 8, Issue 1, Pages: 429-436  
2
.5 Runoff-quality tests  
To perform the runoff quality tests, some specimens  
W W  
2
1
)) 100  
A  (1 (  
(1)  
t
V
w
were selected based on higher compressive strength, which  
is a key factor of pavement’s design in urban areas.  
According to Table 2, for each percentage of fine-grains,  
three samples that had the highest compressive strength were  
chosen.  
3
t w  
where, A is porosity (%), V is sample volume (cm ), ρ is  
3
density of water (g/cm ), W2 is sample dry weight (gr) and  
W1 is sample weight in water (gr).  
100  
9
0
8
0
7
0
6
0
5
0
4
0
3
20  
0
Zeolite  
Perlite  
1
0
0
1/5  
2/5  
3/5  
4/5  
5/5  
Sieve size (mm)  
100  
9
0
8
0
7
60  
0
Pumice  
LECA  
Figure 2: Applied additives in porous concrete mixture designs  
5
0
2
.3 Permeability test  
To conduct permeability tests, a falling-head type  
40  
30  
apparatus, 10.1×10.1×80 cm, made of plexiglass (Figure 4),  
was designed in the Structure Laboratory of Semnan  
University. The system consists of a 20 cm layer of coarse  
gravel on the bottom, the porous-concrete sample (sealed  
tightly to the walls), and 50 cm of water head on the top of  
the sample. Permeability (hydraulic conductivity) of each  
sample is calculated by using Eq. (2), which is based on  
Darcy’s Law and similar device has been mentioned in AC  
2
0
1
0
0
0
1
2
3
4
Sieve size (mm)  
Figure 3: Granulometric curves of the aggregates (above) and  
additives (below) used in the mixing designs  
5
22R standard [25]:  
Table 1: Chemical analysis of Zeolite, Perlite, Pumice,  
LECA and coarse aggregates  
h
1
)
h
2
aL  
At  
(
2)  
K   
ln(  
Chemical Zeolite Perlite Pumice LECA  
Coarse  
(%) aggregates  
%)  
Feature  
(%)  
(%)  
(%)  
(
where, K is permeability (mm/s), a is cross section area of  
the plexiglass container (mm ), A is cross section area of the  
porous-concrete sample (mm ), t is time of water-level drop  
1 2 1  
s) from level h to level h , h is initial height of water level  
mm) and h is final height of water level (mm).  
SiO2  
Al2O3  
Fe2O3  
CaO  
MgO  
Na2O  
K2O  
65.15  
11.83  
1.2  
2.51  
0.64  
1.96  
*
69.5  
12.8  
0.94  
0.8  
0.5  
3.0  
*
48.37 66.05  
12.49 16.75  
38.2  
15.4  
13.6  
4.3  
18.2  
*
7.0  
*
6.8  
2
2
8.07  
8.43  
9.58  
4.36  
*
7.1  
2.46  
1.99  
0.69  
*
(
(
2
2
.4 Compression strength test  
Compressive strength tests were carried out according to  
the BS 1881 standard [26], on the 15×15×15 cm porous  
concrete samples which have been cured for 42 days prior to  
the compressive strength test.  
P2O5  
LOI  
0.27  
12.81  
*
5.1  
1.79  
0.6  
0.21  
20.81  
*
Zero or less than 0.1%  
4
31