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Backhoe A backhoe, also called a rear actor or back actor, is a piece of excavating equipment or digger consisting of a digging bucket on the end of a two-part articulated arm. They are typically mounted on the back of a tractor or front loader. The section of the arm closest to the vehicle is known as the boom, and the section which carries the bucket is known as the dipper or dipper-stick (the terms "boom" and "dipper" having been used previously on steam shovels). The boom is generally attached to the vehicle through a pivot known as the king-post, which allows the arm to slew left and right, usually through a total of around 200 degrees. However, in "360° excavators" it is attached to a turntable, allowing continuous revolution. Modern backhoes are powered by hydraulics.

Construction materials Crushed Stone: Guijo o roca angular es una forma de agregados de construcción, producido típicamente por un depósito de la minería de roca adecuado y romper la roca removida hasta el tamaño deseado mediante trituradoras. Es distinto de grava que se produce por procesos naturales de desgaste y la erosión, y típicamente tiene una forma más redondeada.

Blocking (construction): In construction blocking refers to pieces of wood or other material that run between wall studs in order to provide support and attachment sites for mounted hardware such as cabinets, shelving, vanity tops without a cabinet underneath, or bathroom towel bars.

Wood: "Wooden" and "Heartwood" redirect here. For other uses, see Wooden (disambiguation) and Heartwood (disambiguation). For small forests, see Woodland. For wood as a commodity, see Lumber. For other uses, see Wood (disambiguation). Page semi-protected Wood surface, showing several features Wood is a hard, fibrous structural tissue found in the stems and roots of trees and other woody plants. It has been used for thousands of years for both fuel and as a construction material. It is an organic material, a natural composite of cellulose fibers (which are strong in tension) embedded in a matrix of lignin which resists compression. Wood is sometimes defined as only the secondary xylem in the stems of trees, or it is defined more broadly to include the same type of tissue elsewhere such as in tree roots or in other plants such as shrubs.[citation needed] In a living tree it performs a support function, enabling woody plants to grow large or to stand up by themselves. It also mediates the transfer of water and nutrients to the leaves and other growing tissues. Wood may also refer to other plant materials with comparable properties, and to material engineered from wood, or wood chips or fiber. The Earth contains about one trillion tonnes of wood, which grows at a rate of 10 billion tonnes per year. As an abundant, carbon-neutral renewable resource, woody materials have been of intense interest as a source of renewable energy. In 1991, approximately 3.5 billion cubic meters of wood were harvested. Dominant uses were for furniture and building construction.

Cement: A cement is a binder, a substance that sets and hardens independently, and can bind other materials together. The word "cement" traces to the Romans, who used the term opus caementicium to describe masonry resembling modern concrete that was made from crushed rock with burnt lime as binder. The volcanic ash and pulverized brick additives that were added to the burnt lime to obtain a hydraulic binder were later referred to as cementum, cimentum, c채ment, and cement. Cements used in construction can be characterized as being either hydraulic or nonhydraulic. Hydraulic cements (e.g., Portland cement) harden because of hydration, a chemical reaction between the anhydrous cement powder and water. Thus, they can harden underwater or when constantly exposed to wet weather. The chemical reaction results in hydrates that are not very water-soluble and so are quite durable in water. Non-hydraulic cements do not harden underwater; for example, slaked limes harden by reaction with atmospheric carbon dioxideThe most important uses of cement are as an ingredient in the production of mortar in masonry, and of concrete, a combination of cement and an aggregate to form a strong building material.

Construction management: Construction management or construction project management (CPM) is the overall planning, coordination, and control of a project from beginning to completion. CPM is aimed at meeting a client's requirement in order to produce a functionally and financially viable project