CE200: Asphalt Concrete and Binders
& Wood Questions with Correct
Answers
Emulsified asphalts are prepared by thinning or having their viscosity reduced: -
ANSWERSBy mixing them with water in the presence of anionic or cationic emulsifying
agents
Bitumens constitute a family of materials that consists of: - ANSWERSALL OF THE
ABOVE
- asphaltic materials
- tars
- pitches
A characteristic of timber that makes it similar to portland cement concrete (PCC): -
ANSWERSNONE OF THE ABOVE
- Is the way timber stores moisture
- Is its being a renewable engineering construction material
- Is its strength being dependent on the direction of the load relative to the (wood) grain
Asphalt cements or paving asphalts are graded by their: - ANSWERSviscosity
Cutback asphalts are prepared by thinning or having their viscosity reduced: -
ANSWERSBy mixing them with petroleum derived solvents, such as light, middle, or
heavy distillates
Asphalt binders: - ANSWERSALL OF THE ABOVE
- Are a type of bitumens, which are characterized as organic materials, i.e., they are
made of hydrocarbon chains, like tars and pitches
- May be biogenic, i.e., originating from living tissue, or geogenic, i.e., originating from
inside the Earth itself
- 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
Which option below lists the exogenous trees' components correctly (sorted in outward
direction): - ANSWERSPith, Heartwood, Sapwood, Cambium, Bark
, Asphalt cement or paving asphalt is the thick semisolid material at room temperature
that is: - ANSWERSHeated for the construction of asphalt concrete (AC) pavements
When all the absorbed or free moisture (i.e., the moisture stored in the cell cavity) has
evaporated, the wood or timber reaches its fiber saturation point At which: -
ANSWERSALL OF THE ABOVE
- Depending on the type of the tree, the timber moisture content may reach,
approximately, 21% - 32%
- Any loss of adsorbed or bound moisture, no matter how small, would cause shrinkage,
resulting in deformation
- By loss of moisture in the wood or timber beyond the fiber saturation point, physical
properties of the wood or timber would change
The difference between asphalts and tars may be characterized as follows: -
ANSWERSALL OF THE ABOVE
- 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)
- Tars weather better than asphalts, thus making them more suitable as sealants than
asphalts
- 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
Which sawing pattern is better and why: - ANSWERSQuarter-sawn because the timber
shrinks less in width
For their stability and strength, asphalt concretes (AC) should be made with: -
ANSWERSAngular coarse aggregates
Timber (or wood) used in civil engineering construction is sourced from: -
ANSWERSALL OF THE ABOVE
- Exogenous trees, namely, trees that have annual or annular growth rings
- Softwoods
- Evergreen trees that have needle leaves
Wood or timber can have defects, making the wood or the timber unusable for
construction; such defects may be natural or the result of poor seasoning in the lumber
yard, and may contain: - ANSWERSALL OF THE ABOVE
- Knots
- Shakes
& Wood Questions with Correct
Answers
Emulsified asphalts are prepared by thinning or having their viscosity reduced: -
ANSWERSBy mixing them with water in the presence of anionic or cationic emulsifying
agents
Bitumens constitute a family of materials that consists of: - ANSWERSALL OF THE
ABOVE
- asphaltic materials
- tars
- pitches
A characteristic of timber that makes it similar to portland cement concrete (PCC): -
ANSWERSNONE OF THE ABOVE
- Is the way timber stores moisture
- Is its being a renewable engineering construction material
- Is its strength being dependent on the direction of the load relative to the (wood) grain
Asphalt cements or paving asphalts are graded by their: - ANSWERSviscosity
Cutback asphalts are prepared by thinning or having their viscosity reduced: -
ANSWERSBy mixing them with petroleum derived solvents, such as light, middle, or
heavy distillates
Asphalt binders: - ANSWERSALL OF THE ABOVE
- Are a type of bitumens, which are characterized as organic materials, i.e., they are
made of hydrocarbon chains, like tars and pitches
- May be biogenic, i.e., originating from living tissue, or geogenic, i.e., originating from
inside the Earth itself
- 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
Which option below lists the exogenous trees' components correctly (sorted in outward
direction): - ANSWERSPith, Heartwood, Sapwood, Cambium, Bark
, Asphalt cement or paving asphalt is the thick semisolid material at room temperature
that is: - ANSWERSHeated for the construction of asphalt concrete (AC) pavements
When all the absorbed or free moisture (i.e., the moisture stored in the cell cavity) has
evaporated, the wood or timber reaches its fiber saturation point At which: -
ANSWERSALL OF THE ABOVE
- Depending on the type of the tree, the timber moisture content may reach,
approximately, 21% - 32%
- Any loss of adsorbed or bound moisture, no matter how small, would cause shrinkage,
resulting in deformation
- By loss of moisture in the wood or timber beyond the fiber saturation point, physical
properties of the wood or timber would change
The difference between asphalts and tars may be characterized as follows: -
ANSWERSALL OF THE ABOVE
- 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)
- Tars weather better than asphalts, thus making them more suitable as sealants than
asphalts
- 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
Which sawing pattern is better and why: - ANSWERSQuarter-sawn because the timber
shrinks less in width
For their stability and strength, asphalt concretes (AC) should be made with: -
ANSWERSAngular coarse aggregates
Timber (or wood) used in civil engineering construction is sourced from: -
ANSWERSALL OF THE ABOVE
- Exogenous trees, namely, trees that have annual or annular growth rings
- Softwoods
- Evergreen trees that have needle leaves
Wood or timber can have defects, making the wood or the timber unusable for
construction; such defects may be natural or the result of poor seasoning in the lumber
yard, and may contain: - ANSWERSALL OF THE ABOVE
- Knots
- Shakes
