Comparative laboratory measurement of pervious concrete permeability using constant-head and falling-head permeameter methods

The methods of measuring the permeability of clays in the laboratory are investigated. Constant head tests in the triaxial are best suited for testing large specimen under field stress conditions provided the cell is modified to eliminate leakage. Using this type of test, the validity of Darcy's law is confirmed.Falling head tests in the oedometer are very simple to perform and subject to minimal sources of errors. However, small size specimens may not be totally representative.Indirect evaluations of the permeability from consolidation tests are shown to be unreliable particularly in structured natural clays: evaluation of k from cv measurements in step-loaded tests gives much too low values, constant rate of strain tests strongly overestimate k in the vicinity of σp′ and give nonrepresentative e vs. lg k relations; controlled gradient tests tend to underestimate k at all void ratios. Keywords: permeability, clays, laboratory tests, test equipment, consolidation tests.

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Comprehensive study to accurately predict the water permeability of pervious concrete using constant head method

Construction and Building Materials ◽

10.1016/j.conbuildmat.2021.125046 ◽

2021 ◽

Vol 308 ◽

pp. 125046

Author(s):

Ahmed Abdelhady ◽

Li Hui ◽

Hengji Zhang

Keyword(s):

Water Permeability ◽

Pervious Concrete ◽

Constant Head ◽

Constant Head Method ◽

Comprehensive Study

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Pervious concrete made with electric furnace slag (FEA): mechanical and hydraulic properties

Revista IBRACON de Estruturas e Materiais ◽

10.1590/s1983-41952019000300009 ◽

2019 ◽

Vol 12 (3) ◽

pp. 590-607 ◽

Cited By ~ 1

Author(s):

G. F. B. SANDOVAL ◽

I. GALOBARDES ◽

C. DIAS ◽

A. CAMPOS ◽

B. M. TORALLES

Keyword(s):

Compressive Strength ◽

Hydraulic Properties ◽

Tensile Tests ◽

Pervious Concrete ◽

Hydraulic Behavior ◽

Grain Sizes ◽

Flexural Tensile Strength ◽

Constant Head ◽

Natural Aggregates ◽

Furnace Slag

Abstract The objective of this work is to make feasible the use of FEA slag instead of the conventional bulk aggregate in the pervious concrete (PC) production, reaching the minimum parameters required by NBR16416/2015 and ACI 522R-10. This substitution would minimize the use of natural aggregates, besides taking advantage of a residue that has no specific destination. In order to reach the objective, three FEAs with different grain sizes were chosen: 6-10 mm (A), 10-20 mm (B) and finally a mixture of the two previous ones (C) in the proportion 30-70 respectively. In order to evaluate its mechanical behavior, tests of compressive strength and flexural tensile tests were carried out, while the evaluation of the hydraulic behavior, porosity and constant head permeability test were performed. The compressive strength varies from 19-31MPa and 3-4MPa for flexural tensile strength was obtained. In hydraulic terms, the porosity varied from 15-20% and the permeability coefficient was 10-12mm/s. There is also a direct influence of grains of size less than 4.8 mm (small aggregate) on the compressive strength and permeability of PCs. At the end of the results, it was possible to establish a correlation between the compressive strength, the permeability and the percentage of grains inferior to 4.8mm (sand%), being this positive in relation to the studied variables, that is, the mechanical and hydraulics. Therefore, it has been concluded that the total substitution of conventional aggregates by FEA in CoPe manufacturing will comply with the minimum parameters of NBR 16416/2015.

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Water Permeability of Pervious Concrete Is Dependent on the Applied Pressure and Testing Methods

Advances in Materials Science and Engineering ◽

10.1155/2015/404136 ◽

2015 ◽

Vol 2015 ◽

pp. 1-6 ◽

Cited By ~ 16

Author(s):

Yinghong Qin ◽

Haifeng Yang ◽

Zhiheng Deng ◽

Jiang He

Keyword(s):

Water Permeability ◽

Applied Pressure ◽

Pervious Concrete ◽

Testing Methods ◽

Applied Water ◽

Apparent Permeability ◽

Testing Method ◽

Water Head ◽

Constant Head ◽

Constant Head Method

Falling head method (FHM) and constant head method (CHM) are, respectively, used to test the water permeability of permeable concrete, using different water heads on the testing samples. The results indicate the apparent permeability of pervious concrete decreasing with the applied water head. The results also demonstrate the permeability measured from the FHM is lower than that from the CHM. The fundamental difference between the CHM and FHM is examined from the theory of fluid flowing through porous media. The testing results suggest that the water permeability of permeable concrete should be reported with the applied pressure and the associated testing method.

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Correlation between Permeability and Porosity for Pervious Concrete (PC)

DYNA ◽

10.15446/dyna.v86n209.77613 ◽

2019 ◽

Vol 86 (209) ◽

pp. 151-159 ◽

Cited By ~ 3

Author(s):

Gersson Fernando Barreto sandoval ◽

Isaac Galobardes reyes ◽

Nicole Schwantes-Cezario ◽

André Campos Moura ◽

Berenice Martins Toralles

Keyword(s):

Pervious Concrete ◽

Hydraulic Parameters ◽

Hydraulic Efficiency ◽

Exponential Equation ◽

Efficient Tool ◽

Construction Waste ◽

Structural Applications ◽

Strength Tests ◽

Porosity And Permeability ◽

Constant Head

The aim of this study was to propose a correlation for the hydraulic parameters of pervious concrete (PC). Thus, three aggregates from civil construction waste and one basalt aggregate (reference) were used to produce PC. The ratio c/a (cement: aggregate) 1:3.26 and a w/c ratio of 0.34 were used in all mixtures. Compressive and flexure tensile strength tests were performed to mechanically characterize the mixtures produced, whereas porosity and constant head permeability tests were also carried out to assess the material hydraulic properties.Firstly, the experimental results were compared with the requirements established in international guidelines (ACI 522R-10, NBR 16416(2015) and VTT-R-080225-13). The results complied with the guidelines indicating it is feasible to produce pervious concretes with the sustainable aggregates used in the study in low structural applications such as walkways. On the other hand, a correlation between permeability and porosity was proposed based on Darcy’s and Bernoulli’s laws. The proposed equation, obtained by means of a non-linear regression, is an exponential equation that characterizes the hydraulic efficiency of the internal channels of the material considering the pores interconnection. The correlation between porosity and permeability was finally validated using results from the literature showing the same trend found in laboratory, and therefore it was demonstrated that the proposed correlation in an efficient tool to predict the hydraulic efficiency of pervious concrete.

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Study on the hydraulic conductivity by constant and falling head methods for pervious concrete

Revista IBRACON de Estruturas e Materiais ◽

10.1590/s1983-41952015000300002 ◽

2015 ◽

Vol 8 (3) ◽

pp. 248-259 ◽

Cited By ~ 4

Author(s):

R. BATEZINI ◽

J. T. BALBO

Keyword(s):

Hydraulic Conductivity ◽

Coarse Aggregate ◽

Aggregate Size ◽

Test Methods ◽

Pervious Concrete ◽

Test Results ◽

Permeability Characteristics ◽

Constant Head

The main goal of this paper is to show the analysis of the permeability characteristics of three different mixes of pervious concrete produced with the variation of the coarse aggregate size. Two different test methods were used to achieve the hydraulic conductivity of the samples: falling head and constant head permeability tests. Based on test results it is concluded that the pervious concrete mixes have shown to be good drainable materials. Besides, it was found that the permeability of the mixtures does not seem to depend on the size and gradation of the coarse aggregate.

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