Concrete Materials and Techniques

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Questions and Answers

What is the primary purpose of heavyweight concrete?

Nuclear radiation shielding (correct)

Used for structural strength in buildings

Insulating purposes in construction

Cost-effective construction modifications

Which type of concrete is typically used in the construction of dams?

Mass concrete (correct)

Refractory concrete

Normal-weight concrete

Lightweight insulating concrete

What does the term 'jointing' refer to in concrete construction?

Placing premolded inserts to control cracking (correct)

Creating a rough texture for better adhesion

The process of leveling a slab surface

A method to finish the surface of the concrete

What is the result of bleeding in concrete?

Dry materials sinking and water rising to the surface Signup and view all the answers

Which of the following best describes screeding?

Moving a straight edge across newly-placed concrete Signup and view all the answers

How does refractory concrete differ from regular concrete?

It is shaped before placement in a structure Signup and view all the answers

What is the main purpose of leveling in concrete work?

To create a smooth and true surface Signup and view all the answers

What does edging involve in the context of concrete work?

Preventing damage by rounding off slab edges Signup and view all the answers

What is the primary cause of a seiche phenomenon?

Sudden large-scale sea floor movement Signup and view all the answers

Which of the following signs is intended to warn users about temporary hazardous conditions?

Roadwork sign Signup and view all the answers

What is the effect of a retarder in concrete mixing?

Increases setting time Signup and view all the answers

What does grade resistance represent in vehicle dynamics?

Weight acting parallel to the inclined surface Signup and view all the answers

Which of the following accurately describes the perception time for a driver?

Time required for the driver to react to brakes Signup and view all the answers

What does the term 'heaped volume' refer to in the context of bucket capacity?

Volume contained within the bucket without spillage Signup and view all the answers

In concrete mixing, what role does an admixture play?

Alters the properties of concrete Signup and view all the answers

What does the term 'water line capacity' signify regarding a bucket?

Volume when materials are flush with the bucket bottom Signup and view all the answers

What defines a natural harbor?

A harbor protected from storms and waves by land configuration. Signup and view all the answers

Which component is primarily responsible for rolling resistance?

Tire flexing and surface penetration Signup and view all the answers

What is the primary purpose of a wharf?

To provide a place for ships to dock and load or unload cargo. Signup and view all the answers

What does a prime coat involve in road construction?

Single application onto prepared untreated base Signup and view all the answers

Which of the following accurately describes a jetty?

A landing stage or small pier where boats can dock. Signup and view all the answers

What is the primary function of guide signs?

Inform users about directions and points of interest Signup and view all the answers

Which of the following terms refers to the chemical reaction between cement and water?

Hydration Signup and view all the answers

What term is used to describe the highest wave in a wave group?

Highest wave Signup and view all the answers

Which definition applies to 'Mean Low Water'?

The height of low water over a 19-year period. Signup and view all the answers

What is the impact of a water-reducing agent in concrete mixing?

Increases the consistency without adding water Signup and view all the answers

What characteristic defines a regulatory traffic sign?

It informs users of traffic laws and regulations Signup and view all the answers

What is a dolphin in maritime terms?

A structure for mooring a ship in the open sea. Signup and view all the answers

What does the term 'Storm Surge' refer to?

The abnormal rise of sea level during a typhoon. Signup and view all the answers

Which of the following describes a deepwater wave?

A wave occurring in water depth at least one-half of its wavelength. Signup and view all the answers

Study Notes

Concrete

A construction material made from Portland cement, aggregate, and water
Normal-weight concrete typically weighs 140-160 lb/cu ft
Lightweight insulating concrete weighs 15-90 lb/cu ft and has a 28-day compressive strength of 100-1000 psi
Mass concrete used in structures like dams, where the weight provides strength
Heavyweight concrete use heavy aggregates (barite, magnetite, steel) for radiation shielding
Refractory concrete is cast into the desired shape before placement.
Leveling refers to achieving the correct grade with mortar
Edging rounds off slab edges to prevent chipping
Screeding moves a straight edge across freshly placed concrete
Jointing uses preformed inserts to control cracking due to shrinkage
Bleeding is the settling of dry materials to the bottom of concrete, displacing water
Troweling is the process of smoothing surfaces with a tool
Scaling is the breaking away of hardened concrete surface (1/6-3/16 inch depth) usually in early age of the slab

Harbor Terms

A protected water area for ships (loading, unloading, repairs, etc.)
Natural harbors are protected by natural land formations
Artificial harbors are protected by breakwaters or dredging
Port is a sheltered place for cargo loading/unloading
Fairway is a navigable channel for ships
Wharf is a structure parallel to water for cargo handling
Pier is a landing stage, jetty, floating barge, or pontoon
Jetty is a structure extending into the sea
Dolphin is a berth structure for mooring ships
Significant wave is the hypothetical wave with the average height/period of a group
Highest wave is the tallest wave in a wave group
Mean wave is the wave with average height/period of a wave group

Water Terms

Deepwater waves are where the water depth is at least half the wavelength
Mean Sea Level is the average of sea water level for a period of 19 years
Mean Low Water is the height of low water over a 19-year period
Mean Lower Low Water is the average height of lower low waters over 19 years
Storm Surge is a temporary rise in sea level due to pressure reduction caused by storms and wind
Tsunamis are waves with long periods, often caused by significant sea floor movements
Seiche is a phenomenon of water oscillation with periods of a few minutes to tens of minutes
Seal coat is a thin bituminous surface treatment
Tack coat is an initial bituminous application
Prime coat is a bituminous application on a prepared surface
Perception time is the time for a driver to realize the need for braking
Intellection time is the time to understand a situation and consider options
Emotion time is the time for emotional response to a situation
Volition time is the time taken for the final action

Traffic Terms

Traffic sign is a device conveying information for regulating, warning, or guiding traffic
Regulatory signs inform drivers of traffic laws
Warning signs alert drivers of road conditions
Guide signs show directions, distances, and routes
Roadwork signs provide information about roadwork
Overhead signs display traffic information on wide roads
Plate line capacity is the volume of a bucket when the load is struck off
Struck capacity is the bucket volume when the load is struck
Water line capacity is a level of material within the bucket
Heaped volume is maximum placement in a bucket without spillage
Grade resistance is the vehicle weight component parallel to the inclined surface
Rolling resistance is due to tire flexing/penetration of the travel surface
Total resistance is the combination of grade & rolling resistance
Aggregate is concrete material to reduce cost and shrinkage
Water is required in concrete for hydration of cement
Hydration is the chemical reaction between cement and water to produce hardened cement
Water-reducing agent increases workability and consistency in concrete without altering amount of water

Other Construction Terms

Retarder slows concrete hardening
Accelerator decreases setting time, increases early strength
Pozzolan reduces heat of hydration, increases workability, and reduces segregation
Plasticizers increase concrete workability
Batching is the process of proportioning concrete ingredients.
Admixture is any material added to concrete besides cement, aggregates, and water, altering its properties in various ways

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Description

Explore the essential elements and methods involved in concrete construction. This quiz covers various types of concrete, their properties, and key techniques for working with concrete. Test your knowledge on everything from mixing to finishing processes.