Otro amigo me comenta:
Yo creo que es una variante más del "hormigón ciclópeo".
Puedes hacer un
hormigón fluido y echarle las piedras encima, y se las va tragando....más
volumen y más masa con casi igual coste que lo que tenías antes, o haces lo
contrario, acumulas piedras y les echa el hormigón fluido para que rellenes los
huecos.
En ambos casos se consigue un hormigón de poca resistencia pero que si lo que
necesitas es masa te vale perfectamente: presas de gravedad.
Para terraplenes me parece un poco
excesivo, ¿no?
Un amigo me comenta:
He encontrado este artículo en inglés que
creo que tiene que ver con lo que pedías sobre el hormigón relleno de
rocas. http://management.kochi-tech.ac.jp/PDF/ssms2009/sms09_109.pdf
Yo tengo una experiencia personal positiva
en esto, pero para construcción de relleno de trasdós en el
refuerzo de una pared en una bodega de casa. Lo cierto es que ha
respondido muy bien, pero no aplicamos ningún criterio técnico. Fuimos mezclando hormigón e íbamos echando cantos rodados grandes
que teníamos acumulados. Me consta que ha quedado todo hecho un bloque
macizo. De eso hace ya unos 30 años, sin novedad.
Si sabes algo más de este método, dímelo
por favor.
Puede ser útil también para inserción
medioambiental y paisajística, de obras concretas.
¿ESTO PUEDE SERVIR PARA TERRAPLENES
DE PASO SUPERIOR SOBRE FFCC?
CREO QUE SÍ; PERO NO TENGO EXPERIENCIA
EN
RFC + SCC ; ¿ALGUIEN CONOCE MÁS EL
TEMA?
Rock-Filled Concrete (RFC) - development, investigations and applications: engineers in China are employing Self-Compacting Concrete (SCC) technology to develop and implement Rock-Filled Concrete (RFC) in increasing numbers of hydraulic structures.(CHINA)
A new type of concrete has been under
development in China called Rock-Filled Concrete (RFC). Based on Self-Compacting
Concrete (SCC) technology, engineers have been working on the RFC system since it was first developed in 2003. It has been
employed in a number of hydraulic engineering structures already, in
China.
RFC is produced by pouring ready-mixed SCC into forms con
taining large blocks of rock at least 30cm wide, which are
typically obtained easily near dam sites without the need for crushing.
The SCC fills the void space between the blocks due to its
good fluidity, and thereafter the mix sets to form the RFC mass (see
Fig.l).
[FIGURE 1 OMITTED]
The properties of RFC are affected by the gradation of the
rock blocks, unit rock block content, unit SCC content, and so on. To study the
properties of RFC, tests carried out included compaction, static load,
permeability and in-situ. In addition, cost and environmental impact assessments
of RFC have also been carried out to evaluate the social impacts.
From the results of the tests, it has been
confirmed that the RFC can satisfy the required properties
as a material for dam structures. In addition, the results of the
assessments show that employment of RFC could lead to cost
reduction and improved environmental protection.
Development of RFC
What is RFC
Since its development in 1988, in
Japan, SCC has been used in many practical structures in the world (1),
(2).
However, compared with conventional vibro-compacted
concrete, SCC displays a lower E-modulus, higher shrinkage, a greater rate of
creep and is also more costly in seeking to achieve the same compressive
strength (3). Thus, SCC has seldom been used as a standard
concrete in dam construction. Yet, scope exists to employ SCC in some
degree, especially in light of the further challenge faced by dam engineering of
the need to pay more attention to reducing costs and environmental impacts in
future projects.
To overcome such challenges of the limitations of the use
of SCC, and to improve the economics and environmental performance of dam
projects, engineers in China began to develop RFC technology
as a new type of concrete for structures, especially large-scale structures such
as dams (4). This paper mainly describes the new RFC technology that is
being comprehensively studied and field-tested.
In general, as shown in Fig.2, there are two main
sub-processes in RFC construction: filling the working space
with large-scale blocks of rock (again, generally of size larger than 30cm in
width) to form a rock-block mass; then, either pump SCC into the working space
or pour it directly on to the surface of rock-block mass, and thereafter the SCC
flows down to fill all the void spaces by merit of its own weight and given its
good fluidity and high segregation resistance. It should be noted that the
thickness of rock-block mass is proposed to be less than 1.5m to ensure
effective compactness after the RFC sets.
[FIGURE 2 OMITTED]
Massive concrete structures, in particular concrete dams,
require a reduction of the unit cement content to lower the financial cost as
well as the …
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