Understanding Prestressed Concrete: Principles and Methods
Prestressed Concrete (PSC)
For long-span beams, prestressed concrete (PSC) is used because prestressing prevents cracking. This is achieved by applying an initial compressive load, or ‘prestress,’ using high-strength steel tendons in a concrete member. This counteracts or neutralizes the tensile stresses that arise during its service life.
PSC +
- PSC sections remain uncracked under service loads, reducing the risk of steel corrosion and improving durability. The uncracked section provides higher stiffness
Concrete Cracks: Identification, Monitoring, and Repair Methods
Understanding Concrete Cracks: Types and Causes
A “crack” is a complete or incomplete separation of a structure into two or more parts due to breaking or fracturing.
- Active Crack: Any crack where the mechanism causing the cracking is still active.
- Dormant Crack: Any crack unlikely to become active in the future, or whose movement is insignificant.
- Structural Crack: Caused by dead loads, applied forces, or other external forces, resulting from incorrect design, faulty construction, or overloading.
Understanding Eurocode Design Situations and Structural Actions
Design Situations According to Eurocode Zero
Design situations are sets of physical conditions representing the real conditions occurring during a certain time interval for which the design will demonstrate that relevant limit states are not exceeded.
- Transient design situation: A design situation that is relevant during a period much shorter than the design working life of the structure and which has a high probability of occurrence. A transient design situation refers to temporary conditions of
Bituminous Mixtures and Applications in Road Construction
Irrigation of Primers
Irrigation of primers: The application of a binder with bitumen on a bituminous layer, *not* followed by a sand coverage, to receive further bituminous material. The natural sand used has a uniform granulometry. Before the application of bitumen, it should be watered with surface water to moisten it, but not to the point of saturation. Then, a layer of asphalt agglomerate, called a *watering adherence*, is spread.
Irrigation of Adhesion
Irrigation of adhesion: The application
Understanding Road Signs and Safe Driving Practices
Understanding Road Signs
What does a red, yellow, diamond, and white triangular sign mean?
A red and white triangular sign means yield. A yellow diamond sign indicates a warning or caution.
Using Parking Lights Correctly
When should you use your parking lights?
Use parking lights only when parking.
Driving Through Water
If you drive through a deep puddle, what should you do?
After driving through a deep puddle, you should test your brakes.
Handling a Skidding Car
Which way should you turn if you are going
Read MoreUnderstanding Shallow Foundations: Types and Applications
Shallow Foundations
Shallow foundations are a common type of foundation used when the soil at a shallow depth has sufficient bearing capacity to support the structure’s loads.
1. Footings
Foundation footings are commonly used in areas where the ground has medium to high resistance relative to the structure’s loads and is homogeneous enough to minimize differential settlement.
1.1 Isolated Footings
Isolated footings are individual, typically square concrete pads used to support single columns or posts.
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