Introduction
Geosynthetics have been widely used in geotechnical and environmental engineering for the last 4 centuries ,these products helped in construction engineering field specially in the construction of conventional construction materials that were restricted or very expensive.
The advances on the use of geosynthetics materials in reinforcement and in environmental protection:
there are common types of geosynthetics used for soil reinforcement include geotextiles ,geogrids and geocells. Geotextiles are continous sheets of woven, nonwoven, knitted or stich-bonded fibers or yarns. The sheets are flexiable and permeable and looks like a fabric. Geogrids have a uniformaly distributed array of apertures between their longitudinal and transverse elements. These apertures allow direct contact between soil particles on either side of the sheet. Geocells are thick, three-dimensional networks constructed from strips of polymeric sheet. The strips are connected together forming a net cell that is filled by soil or concrete. In some cases 0.5m to 1m wide strips of polyolefin geogrids are linked together with vertical polymeric rods used to form deep geocell layers called geomattresses.
There are many types of geosynthetics products can be used in environmental protection projects,including geomembranes, geosynthetic clay liners (GCL), geonets, geocomposites and geopipes. Geomembranes are continuous flexible sheets manufactured from one or more synthetic materials. They are impermeable and used as liners for fluid or gas containment and as vapour barriers. Geosynthetic clay liners (GCLs) are geocomposites that are prefabricated with a bentonite clay layer typically incorporated between a top and bottom geotextile layer or...
... middle of paper ...
...il as the backfill if necessary.
The use of relatively short reinforcement.
The staged construction method (Fig. 8), which is one of the main features of this RW system,
consists of the following steps:
1) a small foundation element for the facing is constructed
2) a fullheight GRS wall with wrapped-around wall face is constructed by placing gravel-filled bags at the shoulder of each soil layer and
3) a thin (i.e., 30 cm or more in the thickness) and lightly steelreinforcedconcrete facing (i.e., a FHR facing) is constructed by cast-in-place fresh concrete directly on the wall face after the major part of ultimate deformation of the backfill and the subsoil layer beneath the wall has taken place.
A good connection can be made between the RC facing and the main
body of the wall by placing fresh concrete directly on the geogrid-covered wall face.
The most economical method for ground improvement is aggregate piers. Before aggregate piers were used, engineers had to replace the weak soil with an engineering fill in order to use shallow foundations, but in some cases (load is very high) they had to use deep foundations, which is much more expensive. By using aggregate piers, we can now use shallow foundations in marginal soil without having to replace it. By using compacted aggregate to create stiff pier element, aggregate piers help to increase the bearing capacity, liquefaction resistance, shear strength, rate of consolidation and it reduces settlement.
be built up. An example of this is the first shot we view where we see
Nowadays, it will not be inept to inform that the universe is going over a construction boom. In truth, in the past few decades an entire affair of construction has altered dramatically like all other aspects of life. Currently, construction is no more just about keeping one brick above the other, but a diverse more than that. With the present scenario, the construction work encompasses all the aspects of construction like, performance, optimization, developing and designing. As an outcome, construction chemicals have become an essential part of the world construction industry. These chemicals are typically utilized to impart different properties into the layout.
Minerals are found worldwide and have many uses. The mineral gypsum is just one of the thousands named. Gypsum has always been a critical mineral in the building of many ancient constructions, and is being used still in today’s construction. (The History of Gypsum, 1985) It is speculated that the first use of it was in ancient Greece, where is was called “gypsos”, or “selenite”, but, gypsum’s first recorded use was in Ancient Egypt, where they used it in the building of the Pyramids. They used the material called “Alabaster” (which is a form of gypsum), but later in the 18th century, they realized that gypsum in its natural and raw state, was much too wet, so they altered it to create the building material called “Plaster of Paris”. (The Gypsum Association, n.d.)
...fsite the construction activities can be broken up and completed simultaneously at various locations hence shortening the construction duration by the dispersing the work (Haas, O’Connor, Tucker, Eickmann, Fagerlund, 2000).
Dense to very dense natural and compacted foundation soils had settled a maximum of 4inches or four-tenths of a percent of the wall height. By the comparison of the
16. Francis S. Onderdonk, ‘The ferro-concrete style: reinforced concrete in modern architecture : with four hundred illustrations of European and American ferro-concrete design”, United States, Hennessey + Ingalls, 1998
It is a versatile modern industrial material made of Silica in the form of numerous extremely fine filaments. These fibers might be finer than human hair many times and seem in appearance and feel as silk. It is a light weight material and very strong with favorable bulk strength compared with metals and it can be easily formed by means of molding processes. GF is the most prevail fiber reinforcement that used in construction and among the most adaptable industrial materials. They exhibit different useful properties such as transparency, hardness, resistance to chemical attack, inertness, and stability, as well as desirable fiber properties such as strength, stiffness, and flexibility.
Buildings such as Packard Motor Car Company Building Number Ten (1), Pacific Coast Borax, and the Weavers flour mill all used Hennebique’s (2) method of reinforced concrete construction. This method combined the column and the floor into one single structure. With reinforced concrete being a better load bearing construction material than any stone that could have been used otherwise, these building all had large, open, and efficient interiors that afforded for all kind of different programs. This large unobstructed floor plan design thus became the defacto design for industrial buildings since the building could be fitted with all different kinds of machinery to fit the needs of the owner and his
[17] BS 4550-3.4:1978. Methods of testing cement, Physical tests, Strength tests. British Standards Institution ; 2007.
The materials used for the construction of the designed plan is steel of grade415 and to that for coloums and beams is concrete where grade of concrete for coloums is M40 and for beams is M30.
Throughout the construction industry, technology plays a role to help ease the completion of a project to all of the parties involved. The amount of technology application in the industry supports the belief that technology has a positive impact on project productivity. One of the main materials used in the construction industry that surrounds us every day, in which we overlook, is concrete. Concrete is an art form, in which it takes time and talent in order for it to be used efficiently, to produce its high strength and longevity. However, the downfall of this material is that it is extremely costly and nearly impossible to form it to an aesthetically pleasing surface. In spite of this, what if I told you that there is hope? That the dream of a material made of concrete, producing the same qualities, can be formed to any shape, and used anywhere was a reality.
[A]Cement [B] Cement paste [C] Cement paste & Fine aggregates [D] Mortar & Coarse aggregates.
When trying to design for automated construction systems, all parameters of a construction process must be integrated accurately and constantly to satisfy relevant parties, and finally, the quality of construction materials and products in terms of geometry, physical and design aspects will be changed. In order to reach automated construction goals, all the following aspects have to be fulfilled:
...forms is greatly accommodated by their development of concrete. An arch or dome bonded into solid form by a strong inner layer of concrete sits as one unit, exerting its weight downwards rather than outwards.