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Recognising the different types of building stone
Published in John A. Hudson†, John W. Cosgrove, Understanding Building Stones and Stone Buildings, 2019
John A. Hudson†, John W. Cosgrove
To finish this chapter on artificial stones, we should also remember ‘gabions’, which were mentioned earlier at the end of Section 3.6 on flint. A gabion is a wire mesh box filled with natural or artificial stones, the word gabion coming from the Italian gabbia for a cage or basket. The content of a gabion can be any stone or stone-like material that has a good resistance to weathering, and the wire mesh frame should be galvanised wire or stainless steel wire. So, although the gabion is generally created using natural stone, as a structural building element it is an artificial building block. Examples of a wall with gabion components are shown in the dedication at the beginning of the book and in Figure 3.115.
Concepts for geometrical design
Published in Thompson Roger J., Peroni Rodrigo, Visser Alex T., Mining Haul Roads, 2019
Thompson Roger J., Peroni Rodrigo, Visser Alex T.
A suitable headwall should be constructed from 2 × 1 × 1 m gabions and 2 × 1 × 0.30 m Reno mattress. Gabions are rectangular woven wire mesh baskets filled with rock to create flexible, permeable structures for erosion protection. Reno mattresses are thin, flexible rectangular mesh cages filled with rock to limit movement during high-flow conditions. Because of their flexibility, a Reno mattress is used mainly for scour protection and embankment stability in channel linings.
FLOW Stability
Published in Gerrit J. Schiereck, Introduction to Bed, Bank and Shore Protection, 2017
Gabions consist of loose stones, packed together into larger elements, see appendix A. Gabions can be useful when available stones are not large enough for the flow to be expected or they may be used because they are easy to place. Due to the pores between the stones, a gabion has a smaller relative density than solid rock:
The local scour around bridge piers—a review of remedial techniques
Published in ISH Journal of Hydraulic Engineering, 2022
Ningombam Bishwajit Singh, Thiyam Tamphasana Devi, Bimlesh Kumar
Among the bed armoring countermeasure alternatives to riprap include articulating concrete block (ACB) system, concrete armor units, gabions, etc. Articulating concrete block consists of preformed units that are interlocked and held together by steel rods or cables. They can also be bonded to a geotextile or filter fabric to form a continuous blanket or map. However, scanty information is available on the use of ACB as countermeasure for bridge pier alone. Concrete armor units also known as artificial riprap is another alternative. It comprises of precast concrete units that are placed individually or in interconnected groups. Parker et al. (1998) provide a review of studies conducted on the use of concrete armor units and ACB system as pier scour countermeasures. The advantage of armor units as compared to riprap is that they have greater stability due to interlocking characteristics of their complex shapes. Gabions systems are containers constructed of wire mesh or other materials and filled with loose stones. Either angular rocks or large cobbles can be used to fill the containers of gabions. Maccaferri first developed the gabions in 1884. Like riprap, gabions are also porous and hence not susceptible to uplift forces. Figure 3 shows some typical concrete armor units and gabions. Some researchers like Simons et al. (1984), Parker et al. (1998), etc. attempted to obtain quantitative design guidelines for gabion mattresses. But information on the design and use of gabions as pier scour countermeasure is still scarce.
Comparative evaluation of energy dissipation over short stepped gabion and rigid spillways
Published in Journal of Hydraulic Research, 2020
Seyed Hossein Rajaei, Saeed Reza Khodashenas, Kazem Esmaili
In some of these structures, the application of stepped gabion spillways is a conventional approach. Gabion spillways may be formed into two shapes. In high chutes, a row of gabion boxes is constructed over the body of the dam or over the bed without throughflow (Fig. 2a). In this condition, rather than being the main structure, the gabion is a protective structure that protects the bed and walls of the chute against erosion. The second shape of gabion structures is where the whole body of the dam is constructed as a gabion. In this condition, the gabion spillway is a part of the main body of the structure (Fig. 2b). This shape of the gabion spillways is used in short diversion dams, soil conservation structures, and river engineering plans. This type of gabion structure is most often used in rivers with seasonal flow and flooding regime, with the aim of controlling erosion or river protection, and they are not used in storage structures and high dams, due to the porous body.
Prediction of discharge coefficients for broad-crested weirs using expert systems
Published in ISH Journal of Hydraulic Engineering, 2023
Farzin Salmasi, Farnaz Nahrain, John Abraham, Ali Taheri Aghdam
Broad-crested weirs can be made using a porous medium known as a gabion. Gabion structures are used because of their high permeability and ease of construction. Recently, some researchers simulated flow in rectangular broad-crested porous weirs (Safarzadeh and Mohajeri 2018). They used three stone sizes in the gabion baskets, dm= 0.003 m, 0.007 m, and 0.029 m where dm is the mean grain diameter of the filling material. In a discussion presented by Salmasi and Abraham (2020a), they discuss unexpectedly high values of hydraulic gradient (i) and hydraulic conductivity (k) for flow through the gabion weir reported by (Safarzadeh and Mohajeri 2018).