Assessment of the mechanical performance of recycled unbound materials for pavement subbase layers

The cyclic load triaxial test is a laboratory test that allows studying the mechanical behaviour of unbound granular materials used in base/subbase layers of road pavements. The resilient modulus and permanent strains are required as inputs in structural pavement design. This paper presents some results obtained for recycled materials (crushed concrete aggregate and blended crushed waste aggregate), with a view to promoting their use in pavement structures. Results relating to a reference material (limestone) are also presented, for comparison. All the test results discussed in this paper were obtained in variable cyclic radial pressure (VCP) tests. The tests performed (VCP) aim to study the influence of water content on the resilient modulus of recycled materials, as well as on the resistance to permanent deformation. Using the experimental data as a basis, further modelling work was carried out to establish the stresses developing in base/capping layers in typical Belgian road pavements. These numerical results allow to propose some simplifications of the stress paths applied in the testing procedures and to establish a new test protocol that also considers compaction during construction works. The results of this research work provide an excellent set of findings for the mechanical characterization of unbound base materials through the cyclic triaxial test, and contribute to a better understanding and correct application of recycled materials under geotechnical engineering background

An overview of the brewing process

The first chapter of this book has an introductory character, which discusses the basics of brewing. This includes not only the essential ingredients of beer, but also the steps in the process that transforms the raw materials (grains, hops) into fermented and maturated beer. Special attention is given to the processes involving an organized action of enzymes, which convert the polymeric macromolecules present in malt (such as proteins and polysaccharides) into simple sugars and amino acids; making them available/assimilable for the yeast during fermentation.

Icones plantarum formosanarum nec non et contributiones ad floram formosanam : or, Icones of the plants of Formosa, and materials for a flora of the island, based on a study of the collections of the Botanical survey of the Government of Formosa / By B. Hayata ...

8

Icones plantarum formosanarum nec non et contributiones ad floram formosanam : or, Icones of the plants of Formosa, and materials for a flora of the island, based on a study of the collections of the Botanical survey of the Government of Formosa / By B. Hayata ...

7

Icones plantarum formosanarum nec non et contributiones ad floram formosanam : or, Icones of the plants of Formosa, and materials for a flora of the island, based on a study of the collections of the Botanical survey of the Government of Formosa / By B. Hayata ...

1

Icones plantarum formosanarum nec non et contributiones ad floram formosanam : or, Icones of the plants of Formosa, and materials for a flora of the island, based on a study of the collections of the Botanical survey of the Government of Formosa / By B. Hayata ...

3

Icones plantarum formosanarum nec non et contributiones ad floram formosanam : or, Icones of the plants of Formosa, and materials for a flora of the island, based on a study of the collections of the Botanical survey of the Government of Formosa / By B. Hayata ...

4

Icones plantarum formosanarum nec non et contributiones ad floram formosanam : or, Icones of the plants of Formosa, and materials for a flora of the island, based on a study of the collections of the Botanical survey of the Government of Formosa / By B. Hayata ...

6

Icones plantarum formosanarum nec non et contributiones ad floram formosanam : or, Icones of the plants of Formosa, and materials for a flora of the island, based on a study of the collections of the Botanical survey of the Government of Formosa / By B. Hayata ...

10

Icones plantarum formosanarum nec non et contributiones ad floram formosanam : or, Icones of the plants of Formosa, and materials for a flora of the island, based on a study of the collections of the Botanical survey of the Government of Formosa / By B. Hayata ...

9

Icones plantarum formosanarum nec non et contributiones ad floram formosanam : or, Icones of the plants of Formosa, and materials for a flora of the island, based on a study of the collections of the Botanical survey of the Government of Formosa / By B. Hayata ...

5

Icones plantarum formosanarum nec non et contributiones ad floram formosanam : or, Icones of the plants of Formosa, and materials for a flora of the island, based on a study of the collections of the Botanical survey of the Government of Formosa / By B. Hayata ...

2

The influence of building materials on the residual action of BHC

Residual insecticide activity of BHC vapors from various building materials in controlled humidity chambers in the laboratory were significantly different. Laboratory-reared, first instar nymphs of Dipetalogaster maximus were exposed to vapors of BHC which were being released from the treated surfaces of building materials taken from Mambaí, Goiás.

Modelling the mechanical aspects of the curing process of magneto-sensitive elastomeric materials

In this paper, a phenomenologically motivated magneto-mechanically coupled finite strain elastic framework for simulating the curing process of polymers in the presence of a magnetic load is proposed. This approach is in line with previous works by Hossain and co-workers on finite strain curing modelling framework for the purely mechanical polymer curing (Hossain et al., 2009b). The proposed thermodynamically consistent approach is independent of any particular free energy function that may be used for the fully-cured magneto-sensitive polymer modelling, i.e. any phenomenological or micromechanical-inspired free energy can be inserted into the main modelling framework. For the fabrication of magneto-sensitive polymers, micron-size ferromagnetic particles are mixed with the liquid matrix material in the uncured stage. The particles align in a preferred direction with the application of a magnetic field during the curing process. The polymer curing process is a complex (visco) elastic process that transforms a fluid to a solid with time. Such transformation process is modelled by an appropriate constitutive relation which takes into account the temporal evolution of the material parameters appearing in a particular energy function. For demonstration in this work, a frequently used energy function is chosen, i.e. the classical Mooney-Rivlin free energy enhanced by coupling terms. Several representative numerical examples are demonstrated that prove the capability of our approach to correctly capture common features in polymers undergoing curing processes in the presence of a magneto-mechanical coupled load.