Which of the following sorts the strength of masonry components from highest strength to lowest strength:
a) Mortar, Prism, Unit
b) Mortar, Unit, Prism
c) Prism, Mortar, Unit
d) Unit, Mortar, Prism
e) Unit, Prism, Mortar Aggregates include different sizes of:
1) Riprap, namely large-size pieces of rocks that, depending on size, may be used, in addition to preventing erosion of soils, as the base course in the construction of pavements
2) Gravel or pebbles used as coarse aggregate (CA) in, or filler of, concretes — be they portland cement concrete (PCC) or asphalt concrete (AC) — as well as base course supporting slabs, pavements, or airport runways
3) Natural sand used as fine aggregate (FA) in, or filler of, concretes — be they portland cement concrete (PCC) or asphalt concrete (AC)
4) Crushed used concretes — be they portland cement concrete (PCC) or asphalt concrete (AC) — as well as crushed used masonry units as coarse aggregate (CA) for portland cement concrete (PCC)
5) All of the above are true Aggregates (coarse or fine) are selected based on their physical (size, shape, texture, specific gravity, etc.), chemical (reactivity, as in resistance to chemical attacks), and mechanical (impermeability, volume stability, hardness, toughness, soundness, porosity, etc.) properties. Please choose from the statements below the one that is most appropriate.
1) When selecting a coarse aggregate (CA) for portland cement concrete (PCC), rounded shape and smoother texture, as opposed to angular shape and porous texture, would be considered ideal, as such properties promote better economy of the paste of the PCC, and would lower stress concentration in the hardened paste, as the PCCis loaded — compared to angular, elongated, porous CA
2) When selecting a coarse aggregate (CA) for asphalt concrete (AC), angular shape, and rougher and porous texture, as opposed to rounded shape and smoother texture, would be considered ideal, as such properties promote better particle-to-particle interlocking among the CA in the AC, thus adding to the stability of the AC, as the AC softens in the heat of hot Summer days while loaded
3) As the trend to use recycled concretes and crushed rocks to supply coarse aggregate (CA) for portland cement concrete (PCC) — in response to diminishing naturally available gravel along river beds — the use of chunky but angular, and less than completely smooth-textured CA is now normal.
4) In subscribing to the philosophy of "what is available, that is the best", increasingly, there seems to be little distinctive differentiation between the coarse aggregates (CAs) used in portland cement concrete (PCC) and asphalt concrete (CA)
5) All of the above are true statements Which option below lists the exogenous trees' components correctly (sorted in outward direction):
a) Pith, Heartwood, Sapwood, Cambium, Bark
b) Pith, Sapwood, Heartwood, Annual rings, Bark, Cambium
c) Pith, Sapwood, Heartwood, Cambium, Bark
d) Pith, Heartwood, Sapwood, Late wood, Cambium, Bark
e) None of the above is true Asphalt binders:
1) Are a type of bitumens, which are characterized as organic materials, i.e., they are made of hydrocarbon chains, like tars and pitches
2) May be biogenic, i.e., originating from living tissue, or geogenic, i.e., originating from inside the Earth itself
3) May be natural or native asphalts, i.e., asphalts are the residue of hydrocarbons that rise to the surface of the Earth, and have their smaller chains evaporate over time, or may be the product of a manufacturing process, i.e., asphalts that are the residue of the refining process of petroleum
4) All of the above are true
5) None of the above is true The difference between asphalts and tars may be characterized as follows:
1) Asphalts are produced, for the most part, by the non-destructive distillation of petroleum, whereas tar is the product, for the most part, of the destructive distillation of coal (and sometimes, in smaller quantities, during the petroleum refining process)
2) Tars weather better than asphalts, thus making them more suitable as sealants than asphalts
3) Asphalts are more abundantly produced than tars, and change their viscosity over a smaller range with change in temperature than tars, thus making them more suitable for paving than tars
4) All of the above are true
5) None of the above is true Iron is the product of separating the iron found in the iron ores (in the form of iron oxide) from the soil to which the iron oxide is attached, by using one of the following processes:
1) Pyrometallurgy or smelting (i.e., melting by heating the iron ore in a blast furnace, reducing the iron, and fusing it in the presence of a flux, like ground limestone), thus separating the iron from the impurities in the iron ore.
2) Electrometallurgy, where the iron ore is subjected to intense heat in an electric furnace, thus separating the iron from impurities.
3) Hydrometallurgy, where the iron is dissolved in an aqueous solution, thus separating from impurities, and then precipitated.
4) All of the above are true
5) None of the above is true Steel is a valuable construction material, because:
1) Steel is a versatile civil engineering design and construction material used to erect structures, and as reinforcement for concrete
2) Structural steel is used to design and construct buildings, bridges, and pipelines as reinforcement in portland cement concrete, which is weak in tension and bending, thus requiring reinforcement
3) Because of the high tensile, compressive, bending, and torsional strengths of steel, it can be used in structures (I-beams, angles, round or square tubings); in foundations (steel plates); and portland cement concrete construction (reinforcing bars, because PCC, while very strong in compression, is weak in flexure, and weaker yet in tension)
4) All of the above are true
5) None of the above is true