Abstract Compaction is a fundamental step in pervious concrete production and affects its mechanical hydraulic properties. In this study, two mixtures were compacted with three different energies, distributed layers. The effects on porosity, strength conductivity evaluated. increase compaction energy resulted proportional reduction porosity. Increases compressive from 17 to 36% observed. Howeve...

This paper reports the composition and horizontal distribution of an earthworm community at El Molar (Madrid), and the underlying causes of its distribution. Five species of earthworms were found. The most abundant species were Hormogaster elisae, Allolobophora rosea and Allolobophora caliginosa trapezoides, which showed an aggregate-type distribution. Coarse sand, organic matter and nitrogen a...

In this study, we measure effective diffusion coefficients for trichloroethene in undisturbed soil samples taken from Picatinny Arsenal, New Jersey. The measured effective diffusion coefficients ranged from 0.0053 to 0.0609 cm2/s over a range of air-filled porosity of 0.23-0.49. The experimental data were compared to several previously published relations that predict diffusion coefficients as ...

This paper investigates the effect of different methods of carbon nanotubes distribution in a thin matrix on static and dynamic behavior of the nanocomposite. Five different symmetric patterns of distribution are considered, including four parabolic patterns and a linear one. For each pattern, the effective mechanical properties of the resultant nanocomposite are calculated using the rule of mi...

The problem of voids and porosity has long plagued the dental technician. Many times an otherwise acceptable casting has had to be discarded because voids or porosities have developed within the casting. Because of numerous variables a technician often does not know the cause of the casting failure. Many investigators have studied variables that may affect the occurrence of voids and porosities...