1.
Oclassifies Inorganic soils for suitability as subgrade materials in terms of good drainage and bearing capacity.
Correct Answer
B. AASHTO SOIL CLASSIFICATION SYSTEM
Explanation
The AASHTO Soil Classification System is used to classify inorganic soils based on their suitability as subgrade materials in terms of good drainage and bearing capacity. This system provides a standardized method for categorizing soils based on their physical properties such as grain size and plasticity. By using this classification system, engineers and construction professionals can determine the appropriate use of different types of soils in road construction and other infrastructure projects.
2.
The moisture content at which a soil changes from the liquid state to theplastic state, measured when soil in a shallow dish flows to close a 12.5 mm groove after25 drops from 1 cm.
Correct Answer
A. Liquid Limit (LL)
Explanation
The liquid limit (LL) is the moisture content at which a soil transitions from a liquid state to a plastic state. This transition is measured by determining the point at which soil in a shallow dish flows to close a 12.5 mm groove after 25 drops from 1 cm. The liquid limit is an important property of soil that helps determine its behavior and engineering characteristics.
3.
Ncrthe water content at which a silt or clay material will just begin to crumble when rolled into a tread approx 3.2mm (1/8 inch) in diameter.
Correct Answer
B. Plastic Limit (PL)
Explanation
The plastic limit (PL) is the water content at which a silt or clay material will just begin to crumble when rolled into a tread approximately 3.2mm (1/8 inch) in diameter. This means that if the water content of the material is below the plastic limit, it will not crumble when rolled into a tread, indicating that it is too dry. If the water content is above the plastic limit, the material will be too wet and will not crumble when rolled into a tread either. Therefore, the plastic limit represents the boundary between the dry and wet states of the material.
4.
Is defined as the Liquid Limit minus the Plastic Limit: LL – PL = PI, that is the range of water content over which sediment behaves.
Correct Answer
C. Plasticity Index (PI)
Explanation
The Plasticity Index (PI) is the correct answer because it is defined as the difference between the Liquid Limit (LL) and the Plastic Limit (PL). The PI represents the range of water content over which sediment behaves. It is an important measure in geotechnical engineering as it indicates the plasticity and compressibility of soil. A higher PI value indicates a higher clay content and greater potential for settlement and deformation. Conversely, a lower PI value indicates a higher sand or silt content and less potential for deformation.
5.
Are tests performed on soils passing the No.40 sieve
Correct Answer
B. ATTERBERG LIMITS
Explanation
The Atterberg limits are a set of tests used to determine the consistency and plasticity of soils. These tests include the Plastic Limit (PL) and Liquid Limit (LL), which are used to calculate the Plasticity Index (PI). The Plastic Limit (PL) is the moisture content at which a soil transitions from a plastic to a semi-solid state, while the Liquid Limit (LL) is the moisture content at which a soil transitions from a liquid to a plastic state. These tests are important in assessing the behavior and suitability of soils for various engineering applications.
6.
Soil, crushed stone, and sand used to raisean existing grade, or as a man-made-deposit, generallyused under spread footings, pavers, or concrete slabs ongrade.
Correct Answer
C. FILL MATERIALS
Explanation
The correct answer is "FILL MATERIALS" because the given explanation mentions that soil, crushed stone, and sand are used to raise an existing grade or as a man-made deposit. These materials are commonly used as fill materials to level or raise the ground before constructing spread footings, pavers, or concrete slabs on grade.
7.
Esoil materials conforming to above General Fill requirements and to ASTM C 33, size 67, with a sand equivalent of not < than 50%, used to prevent the movement of fine particles out of soils and other natural materials through seepage.
Correct Answer
A. Granular Fill or Filters
Explanation
The given passage mentions the use of "esoil materials conforming to above General Fill requirements and to ASTM C 33, size 67, with a sand equivalent of not < than 50%". This indicates that the material being used should have specific characteristics such as being granular and having a certain sand equivalent value. Granular Fill or Filters is the correct answer as it aligns with the description provided in the passage.
8.
Soil materials suitable as fill or subgrade, selected laboratory-approved pit-run gravel, disintegrated granite, sand, shale, cinders or other similar materials with not more than 35% fraction passing the No. 200 sieve.
Correct Answer
A. Borrow Fill
Explanation
The given answer, "Borrow Fill," is the correct answer because it refers to soil materials that are suitable for use as fill or subgrade. These materials can include selected laboratory-approved pit-run gravel, disintegrated granite, sand, shale, cinders, or other similar materials. The specification of not more than 35% fraction passing the No. 200 sieve indicates that the material should have a certain level of coarseness, making it suitable for filling purposes. Therefore, "Borrow Fill" accurately describes the type of soil material mentioned in the given statement.
9.
Are hard durable fragments of stone and a filler of sand or othrfinely divided mineral matter, free from vegetable matter and lumps of clay, complying with the following AASHTO METHODS T-11 and T-26 Grading Requirements
Correct Answer
A. Base Course Materials
Explanation
The given answer "Base Course Materials" is the correct answer because the statement mentions that the materials should comply with AASHTO METHODS T-11 and T-26 Grading Requirements. Base course materials are typically used in road construction and are required to have specific grading and durability properties.
10.
Construction materials consisting of synthetic components made for use with or within earth materials generally
Correct Answer
A. GEOSYNTHETICS
Explanation
Geosynthetics are construction materials made of synthetic components that are used with or within earth materials. They are designed to enhance the performance and durability of earth structures such as roads, slopes, and retaining walls. Geosynthetics can include materials like geotextiles, geogrids, and geomembranes, which are used to provide reinforcement, filtration, drainage, and erosion control. They are widely used in civil engineering and geotechnical applications to improve the strength and stability of soil and rock masses.
11.
The most common geosynthetics, consist of woven or nonwoven fabric made from polymeric materials such as polyester or polypropylene
Correct Answer
C. Geotextiles
Explanation
Geotextiles are the most common type of geosynthetics, which are materials used in civil engineering projects to improve soil stability and prevent erosion. Geotextiles are typically made from polyester or polypropylene and can be either woven or nonwoven fabric. They are used for various applications such as filtration, drainage, separation, and reinforcement. Geocomposites and geomembranes are also types of geosynthetics, but they are not as commonly used as geotextiles.
12.
Tcontinuous polymeric sheets that are impermeable; the most frequently used for ground applications and pond lining are thermoplastic products manufactured from high-density polyethylene (HDPE) and polyvinyl chloride (PVC)
Correct Answer
A. Geomembranes
Explanation
Geomembranes are continuous polymeric sheets that are impermeable, making them suitable for applications such as ground lining and pond lining. They are commonly made from thermoplastic materials like HDPE and PVC. Geomembranes are different from geotextiles and geocomposites, which serve different purposes in geotechnical engineering.
13.
A combination of geosynthetic components, usually sheet or edge drainsconsisting of a prefabricated core to which a geotextile filter is bonded. The core provides void space to which water can flow in-plane while the geotextile filter keeps soil from filling the voids created by the core.
Correct Answer
B. Geocomposites
Explanation
Geocomposites are a combination of geosynthetic components that consist of a prefabricated core bonded with a geotextile filter. The core allows water to flow through it, while the geotextile filter prevents soil from filling the voids created by the core. This combination of components makes geocomposites effective in drainage applications, as they allow water to pass through while keeping the soil in place. Geomembranes and geotextiles, on the other hand, do not have the same combination of components and characteristics as geocomposites.
14.
Consist of a continuous extrusion of polymeric ribs, forming void space throughwhich provide in-plane flow capacity; available with or without bonded geotextile filters.Geonets with bonded geotextile filters are sometimes called composite drainage nets (CDNs).
Correct Answer
B. Geonets
Explanation
Geonets are a type of drainage material that consist of a continuous extrusion of polymeric ribs. These ribs create void spaces that allow for in-plane flow capacity. Geonets can be used with or without bonded geotextile filters. When geonets are combined with geotextile filters, they are referred to as composite drainage nets (CDNs). Geonets are commonly used in various applications such as drainage systems, landfill liners, and erosion control.
15.
Three-dimensional prefabricated polymeric systems ranging from 100mm to200mm high. The geocell systems are collapsed for delivery to the site, spread open andfilled to form a three-dimensional reinforced mattress upon arrival at a site. Originallydeveloped to rapidly stabilize soft subgrades for mobilization of large equipment, they are nowfrequently used for protection and stabilization of steep slope surfaces and protective liningsfor channels.
Correct Answer
A. Geocells
Explanation
Geocells are three-dimensional prefabricated polymeric systems that can range from 100mm to 200mm high. These systems are collapsed for delivery to the site and then spread open and filled to form a three-dimensional reinforced mattress. They were originally developed to quickly stabilize soft subgrades for the mobilization of large equipment. However, they are now commonly used for the protection and stabilization of steep slope surfaces and as protective linings for channels. Therefore, geocells are the correct answer in this context.
16.
Physical barrier thatprevents termites from accessing thewood in a home. There are a variety ofmethods.
Correct Answer
B. pHysical Barriers
Explanation
Physical barriers are a type of termite prevention method that physically blocks termites from accessing the wood in a home. These barriers can be made from materials such as metal, concrete, or sand, and are installed around the perimeter of the building or under the foundation. By creating a physical barrier, termites are unable to penetrate the barrier and reach the wood, thus preventing infestation and damage.
17.
A layer of sand with uniform sizeparticles, area must be large enough toprevent the termite from moving throughit or prevents its use in "tunnel" construction.
Correct Answer
A. Termite Resistant Sand
Explanation
Termite Resistant Sand is the correct answer because it forms a layer of sand with uniform-sized particles that acts as a barrier against termites. The sand particles are large enough to prevent termites from moving through it or using it for tunnel construction. This sand acts as a deterrent and helps protect against termite infestation.
18.
Steel mesh product that is fine enough to keep even tiny termites from passing through it.Termite Mesh is used in slab construction, also used to wrap pipes and other accessareas.
Correct Answer
C. Termite Mesh
Explanation
Termite Mesh is the correct answer because it is a steel mesh product that is fine enough to prevent even tiny termites from passing through it. It is commonly used in slab construction to create a barrier against termites and is also used to wrap pipes and other access areas to prevent termite infestation.
19.
The objective is to establish a continuous termiticide barrier betweensoil access routes and the structure, either killing or repeling subterranean termites thatattempt to reach the structure. A termiticide is a type of chemical used to control termites.
Correct Answer
A. Chemical Barriers:
Explanation
Chemical barriers are used to establish a continuous termiticide barrier between soil access routes and the structure. This barrier is meant to either kill or repel subterranean termites that try to reach the structure. Termiticides are a type of chemical specifically designed to control termites. Therefore, chemical barriers are an effective method for preventing termite infestations and protecting structures from termite damage.
20.
Almost always applied during construction to the soil and foundation; or the use of termiteresistant building products, from drywall to floor joists treated with borates before use inhome construction.
Correct Answer
A. Pre-construction chemical barriers
Explanation
Pre-construction chemical barriers refer to the application of chemicals to the soil and foundation before construction begins. This is done to prevent termite infestations and protect the building from termite damage. These barriers act as a deterrent for termites, preventing them from accessing the structure. By treating the soil and foundation with termiticides, the risk of termite infestation is greatly reduced, ensuring the longevity and safety of the building.
21.
Applied by rodding or trenching around the base of foundations,plumbing, utility entrances, expansion joints, and where twoslabs will join, applying 4 gallons of termiticide per 10 linearfeet; each foot of depth should receive 4 gallons per 10 linearfeet; for trenches no wider than 6 inches, apply termiticide tothe trench, and mix with backfill. Hollow block voids offoundations should also be treated with 4 gallons of termiticideper 10 linear feet.
Correct Answer
B. Vertical barriers
Explanation
Vertical barriers are applied by rodding or trenching around the base of foundations, plumbing, utility entrances, expansion joints, and where two slabs will join. The application involves applying 4 gallons of termiticide per 10 linear feet, with each foot of depth also receiving 4 gallons per 10 linear feet. Additionally, hollow block voids off foundations should be treated with 4 gallons of termiticide per 10 linear feet. Therefore, the correct answer is vertical barriers.
22.
EApplying one gallon of termiticide per 10 square feet, usually by coarse spray at lowpressure. All termite treatments to slab construction should include horizontal barriers,which are relatively easy to apply.
Correct Answer
C. Horizontal barriers
Explanation
Horizontal barriers are recommended for termite treatments in slab construction because they are relatively easy to apply. These barriers involve applying one gallon of termiticide per 10 square feet, usually by coarse spray at low pressure. By creating a barrier at ground level, horizontal barriers help prevent termites from entering the structure through the slab. This method is effective in deterring termites and can be easily implemented during the construction process.
23.
Involves drilling through the slab floor and injecting termiticides into the soil atregular intervals.
Correct Answer
A. Slab treatment
Explanation
Slab treatment involves drilling through the slab floor and injecting termiticides into the soil at regular intervals. This method is commonly used in basements and crawl spaces to create vertical barriers against termites. By injecting termiticides into the soil, the treatment effectively creates a barrier that prevents termites from entering the structure through the slab. This method is considered effective in preventing termite infestations and protecting the structure from potential damage caused by termites.
24.
Trenches are dug around the foundation, termiticide applied and the trench filled back in. Chemicals may also be injected into the soil in the crawl space/basement and around the foundation.
Correct Answer
A. Basements and Crawl Spaces
Explanation
The correct answer is Basements and Crawl Spaces. This answer is supported by the information given in the question, which mentions that chemicals may be injected into the soil in the crawl space/basement and around the foundation. This indicates that basements and crawl spaces are areas where termiticide treatment is commonly applied. Additionally, the mention of trenches being dug around the foundation suggests that termiticide may also be applied in this area, further supporting the answer choice.
25.
The objective is to continuously attract the termite workers to forage on aslow-acting insect-growth regulator (IGR) called hexaflumuron to eliminate the entireworkers population and the entire colony. The system employs baits and monitoringdevices installed where evidence of infestation is found
Correct Answer
A. Bait System:
Explanation
The correct answer is Bait System. The objective of the system is to attract termite workers to forage on a slow-acting insect-growth regulator called hexaflumuron in order to eliminate the entire worker population and the entire colony. The system employs baits and monitoring devices installed where evidence of infestation is found. This suggests that the bait system is a method used to control termite infestations by strategically placing bait traps to attract and kill termites. The vertical and horizontal barriers mentioned are likely types of bait traps used in the system.
26.
A dark brown to black cementitious material, solid or semisolid,composed of bitumens which occur in nature but are obtainedartificially in refining petroleum, and which when mixed with graded aggregates is used as paving material by placing, shaping, and compactingwhile hot over a prepared base.
Correct Answer
C. HOT MIX ASpHALT or ASpHALTIC
CONCRETE
Explanation
The correct answer is "HOT MIX ASPHALT or ASPHALTIC CONCRETE" because it accurately describes the dark brown to black cementitious material made from bitumens obtained in petroleum refining. This material is mixed with graded aggregates and used for paving by placing, shaping, and compacting while hot over a prepared base.
27.
Asphaltic concrete prepared with a relatively light and slow-curing asphalt, placed over a prepared surface withoutheat; hardens to a state that is less firm and durable than hot-mix asphaltic concrete
Correct Answer
A. COLD MIX ASpHALT OR ASpHALTIC CONCRETE
Explanation
Cold mix asphalt or asphaltic concrete is the correct answer because it is prepared with a relatively light and slow-curing asphalt, placed over a prepared surface without heat. It hardens to a state that is less firm and durable than hot-mix asphaltic concrete. This type of asphalt is commonly used for temporary repairs, patching potholes, and low-volume roadways. It does not require heating during the mixing and laying process, making it more convenient and cost-effective for certain applications.
28.
Formed by grading and compacting layers of crushedstone or gravel, then binding the top layer with asphalt to stabilize the stone, provide a smoother surface, and seal against water penetration.
Correct Answer
B. ASpHALTIC MACADAM
Explanation
Asphaltic macadam is the correct answer because it is a type of road surface that is formed by grading and compacting layers of crushed stone or gravel, and then binding the top layer with asphalt. This process helps to stabilize the stone, provide a smoother surface, and seal against water penetration. Cold mix asphalt or asphaltic concrete and hot mix asphalt or asphaltic concrete are also types of road surfaces, but they do not specifically mention the use of crushed stone or gravel in their formation.
29.
When one or more courses or layers of asphalt an asphaltleveling course made of an asphalt and aggregate mixture of variable thickness tocorrect the contour of existing surface, are placed on existing pavement.
Correct Answer
A. ASpHALT OVERLAY
Explanation
An asphalt overlay is a process where one or more courses or layers of asphalt, known as an asphalt leveling course, are placed on top of an existing pavement to correct the contour of the surface. This overlay is made of an asphalt and aggregate mixture with a variable thickness. It is a commonly used method to improve the condition and smoothness of existing roads or pavements. The other options, hot mix asphalt or asphaltic concrete, and cold mix asphalt or asphaltic concrete, are types of asphalt materials used in the overlay process.
30.
Division 3 of Materials Specification
Correct Answer
A. Concrete
Explanation
The given answer "Concrete" is the correct answer because the question is asking for the division of materials specification, and out of the options provided (Concrete, Masonry, General notes, Site works), "Concrete" is the only option that falls under the category of materials specification. The other options are either specific types of construction materials (Masonry) or general categories that may or may not include materials (General notes, Site works).
31.
In materials specification, what is devision 2
Correct Answer
A. Site works
Explanation
Division 2 in materials specification refers to Site works. This division includes all the activities and materials required for the preparation and development of the construction site. It involves tasks such as site clearing, excavation, grading, drainage, and landscaping. This division ensures that the site is properly prepared and ready for the construction process to begin.
32.
One of the oldest manufactured building materials used as a mortar and plaster by early civilizations.
Correct Answer
A. Lime
Explanation
Lime is one of the oldest manufactured building materials that was used as a mortar and plaster by early civilizations. It has been used for centuries due to its adhesive and binding properties, making it an effective material for construction purposes. Lime is made by heating limestone, which causes it to release carbon dioxide and leave behind calcium oxide. This calcium oxide, or quicklime, is then mixed with water to create a paste that hardens over time through a process called carbonation. The resulting lime mortar and plaster have been used in various ancient structures, showcasing the durability and effectiveness of lime as a building material.
33.
The process of mixing quicklime with water during which water is absorbed and heat isenergetically evolved, driving off much of the excess water in the form of steam.
Correct Answer
A. Slaking
Explanation
Slaking refers to the process of mixing quicklime with water, where the water is absorbed and heat is energetically evolved. This process drives off excess water in the form of steam. Therefore, slaking is the correct answer as it accurately describes the given process.
34.
Like lime, was used as a plaster by the Egyptians, Greeks and Romans
Correct Answer
B. GYPSUM
Explanation
Gypsum was used as a plaster by the Egyptians, Greeks, and Romans. It was a popular choice for its ability to harden quickly and create a durable surface. Gypsum is a soft sulfate mineral that can be easily ground into a powder and mixed with water to form a paste. When this paste is applied to walls or ceilings, it hardens into a solid material, providing a smooth and even finish. The Egyptians, Greeks, and Romans recognized the benefits of gypsum and utilized it extensively in their construction projects.
35.
___________rock is ground fine and heated (calcined) to between 325 °F. to 340 °F. when it loses about three-fourths of its combined water. The remaining product is Plaster of Paris, if pure gypsum is used, or hard wall plaster if 39.5 % impurities are present.
Correct Answer
A. Gypsum rock
Explanation
Gypsum rock is ground fine and heated to a specific temperature range, causing it to lose about three-fourths of its combined water. The resulting product is either Plaster of Paris if pure gypsum is used, or hard wall plaster if there are impurities present. This process is used to create these specific types of plaster materials.
36.
Gypsum plaster is rendered more plastic by the addition of _________. Fiber or hair is alsosometimes added for greater cohesiveness. The fiber may be hemp, sisal or jute; the hair is generally cleaned goat or cattle hair.
Correct Answer
B. Hyrdated lime
Explanation
Hydrated lime is added to gypsum plaster to make it more plastic. This means that hydrated lime improves the workability and flexibility of the plaster, making it easier to shape and mold. The addition of hydrated lime also enhances the cohesiveness of the plaster, allowing it to adhere better to surfaces. The use of fiber or hair, such as hemp, sisal, or jute, further increases the cohesiveness of the plaster. The hair, typically from goats or cattle, is cleaned before being added to the plaster.
37.
The Romans were the first to develop cement made by mixing slaked lime with pozzolana (volcanic ash) which hardened under the water, but lost the art with the fall of the Roman Empire. In 1756,Smeaton, an Englishman, rediscovered hydraulic cement, but it was not until 1824 that Aspdin, an English bricklayer and mason, invented and patented Portland cement. Today, the word “cement” generally refers to Portland cement which is principal type of cement in use.
Correct Answer
C. Cement
Explanation
The Romans were the first to develop cement made by mixing slaked lime with pozzolana (volcanic ash) which hardened under water. However, they lost this knowledge after the fall of the Roman Empire. In 1756, an Englishman named Smeaton rediscovered hydraulic cement. It was not until 1824 that Aspdin, an English bricklayer and mason, invented and patented Portland cement. Today, the term "cement" generally refers to Portland cement, which is the principal type of cement in use.
38.
________ cement is obtained by finely pulverizing clinker produced by calcining to incipient fusion an intimate and proportioned mixture of argillaceous (silica, alumina) and calcareous (lime) materials with iron oxide and small amounts of other ingredients. Gypsum is added in the final grinding process to regulate the setting time of the cement.
Correct Answer
A. Portland
Explanation
Portland cement is obtained by finely pulverizing clinker produced by calcining an intimate and proportioned mixture of argillaceous and calcareous materials with iron oxide and small amounts of other ingredients. Gypsum is added in the final grinding process to regulate the setting time of the cement.
39.
(also called stainless cement because it is free of iron impurities which stain porous marbles, some granites and limestone and other light-colored stones)
Correct Answer
B. White cement
Explanation
White cement is the correct answer because it is free of iron impurities that can stain porous marbles, granites, limestone, and other light-colored stones. This type of cement is commonly used in applications where aesthetics and color consistency are important, such as in architectural designs or decorative elements. Unlike brown, grey, or aluminum cement, white cement provides a clean and uniform appearance, making it suitable for projects that require a lighter color palette.
40.
Utilizes bauxite, the ore from which aluminum is made, as the major raw material. It is called aquick-setting cement and its advantage is that after setting for 24 hours, alumina cementattains a compressive strength equal to the strength developed in ordinary cement only at anage of 28 days. The quick hardening produces considerable heat advantageous in coldweather construction.
Correct Answer
B. Alumina cement
Explanation
Alumina cement is the correct answer because the passage states that it utilizes bauxite, the ore from which aluminum is made, as the major raw material. Additionally, it is referred to as a quick-setting cement and has the advantage of attaining a compressive strength equal to ordinary cement after only 24 hours, compared to the 28 days needed for ordinary cement. The quick hardening of alumina cement also produces heat, which is beneficial for construction in cold weather.
41.
Are prepared mixtures of Portland cement with hydrated lime, granulated slag, silica, etc.Small additions of calcium stereate, petroleum, colloidal clays and other admixtures with theingredients and proportions varying widely and usually patented
Correct Answer
A. Masonry cements
Explanation
Masonry cements are prepared mixtures of Portland cement with hydrated lime, granulated slag, silica, etc. They may also contain small additions of calcium stereate, petroleum, colloidal clays, and other admixtures. The ingredients and proportions of masonry cements can vary widely and are often patented. Masonry cements are commonly used in construction for laying bricks, blocks, and stones.
42.
Cements made of natural raw materials found mixed in the correct proportions, needing onlygrinding and burning in a kiln to produce a cement. Their use today has largely been replacedby Portland cement. Natural cements sets more rapidly than Portland cement and are slowerin developing strength.
Correct Answer
C. Natural cements
Explanation
Natural cements are made from natural raw materials that are found mixed in the correct proportions. They only require grinding and burning in a kiln to produce cement. However, their use has been largely replaced by Portland cement. Natural cements have the advantage of setting more rapidly than Portland cement but are slower in developing strength. This suggests that natural cements may be useful in applications where quick setting is desired, but may not be as strong as Portland cement in the long term.
43.
Type of cement made of lime mortar and pozzolanic material. Various natural materialscontain active silica, among them pozzolan (volcanic ash), granulated slag and pumice. Slagcement is a ___________ cement.
Correct Answer
D. Pozzolanic cement
Explanation
Pozzolanic cement is a type of cement that is made by combining lime mortar with a pozzolanic material, such as volcanic ash, granulated slag, or pumice. These materials contain active silica, which reacts with lime to form cementitious compounds. Pozzolanic cement is commonly used in masonry applications due to its ability to improve workability and durability of mortar. It is different from other types of cement like masonry cements, alumina cements, and natural cements, which have different compositions and properties.
44.
_____________ and ________ cements are not used except in unexposed structures where mass and weight rather than strength are essential features.
Correct Answer
B. Natural and slag
Explanation
Natural and slag cements are not used except in unexposed structures where mass and weight rather than strength are essential features. This means that these types of cements are not suitable for structures that require high strength, but they can be used in structures where the main concern is the mass and weight of the materials used.
45.
In reinforced-concrete work or in structures exposed to the elements, ______ cement is invariably employed because of its uniform quality and the high strength which it rapidly acquires.
Correct Answer
A. Portland
Explanation
In reinforced-concrete work or in structures exposed to the elements, Portland cement is invariably employed because of its uniform quality and the high strength which it rapidly acquires. Portland cement is a type of hydraulic cement that is widely used in construction due to its ability to harden under water and form a strong bond with other materials. It is known for its consistent quality and quick setting time, making it suitable for various applications where durability and strength are required.
46.
Cement should be properly protected after delivery at the building site from injury through contact with __________; stored in shed with a wood floor raised about 12” from the ground
Correct Answer
C. Dampness
Explanation
Cement should be properly protected after delivery at the building site from injury through contact with dampness. Dampness can cause the cement to become wet and lose its strength, resulting in a weakened structure. Storing the cement in a shed with a wood floor raised about 12" from the ground helps to prevent moisture from seeping into the cement and ensures its quality is maintained.
47.
In storing cement bags in Piles, it should be limited to how many sacks in height
Correct Answer
B. 12
Explanation
The correct answer is 12. When storing cement bags in piles, it is important to limit the height to avoid any potential safety hazards or instability. By limiting the height to 12 sacks, the weight and pressure on the lower sacks can be evenly distributed, reducing the risk of collapse or damage to the bags. This ensures a stable and secure storage arrangement for the cement bags.
48.
The proportioned mixture of cement, aggregate and water, which when properly proportioned, is at first a plastic mass which can be cast or molded into predetermined size or shape
Correct Answer
C. Concrete
Explanation
Concrete is a mixture of cement, aggregates, and water that, when properly proportioned, forms a plastic mass. This plastic mass can be cast or molded into a predetermined size or shape. Cement is the binding agent that holds the mixture together, while aggregates provide strength and stability. Water is added to the mixture to initiate the chemical reaction that causes the cement to harden and form a solid structure. Therefore, the correct answer is concrete.
49.
The hardening of concrete is called
Correct Answer
A. Setting
Explanation
Setting is the correct answer because it refers to the process of hardening or solidifying of concrete after it has been mixed with water. During setting, the concrete undergoes a chemical reaction known as hydration, where the water reacts with the cement particles to form a solid mass. This process gives the concrete its strength and durability. Batching refers to the process of measuring and combining the ingredients of concrete, while curing is the process of maintaining the moisture and temperature conditions to allow for proper hydration and strength development. Forming refers to the process of creating the desired shape or structure using molds or formwork.
50.
When cement is mixed with water and a fine aggregate or less than 6mm (¼“), it is known as
Correct Answer
B. Mortar, stucco or cement plaster
Explanation
When cement is mixed with water and a fine aggregate or less than 6mm (¼“), it is known as mortar, stucco or cement plaster. Mortar is a mixture used in construction for binding bricks, stones, or other materials together. Stucco is a plastering material used for coating walls and ceilings. Cement plaster is a type of plaster made from cement, sand, and water, commonly used for finishing interior and exterior walls. All three terms refer to mixtures involving cement, water, and a fine aggregate, making them the correct answer choices.