Construction Engineering Quiz

Pile Types

• Two main pile types exist: displacement piles (steel H piles) and replacement piles (barrettes).

Tremie Pipe Advantages

• Tremie pipes prevent concrete contamination.

Formwork Removal Priority

• Walls and columns can be removed first because they support themselves.
• Beams and slabs require more time for removal due to weaker horizontal support.

Dewatering Pumps

• Submerged pumps and suction pumps are used for dewatering.

Self-Compacting Concrete

• Self-compacting concrete is highly workable and pumpable.

Concrete Additives for Self-Compacting Concrete

• Superplasticizers are added to concrete to make it self-compacting (pumpable and flowable).

Formwork for Tall Buildings

• Fly Form/Table Form is a suitable formwork for speeding up slab construction in tall buildings.

Continuous Beam Steel

• Top steel (cantilever) and bottom steel (span) are used for continuous beams.
• Additionally, steel is required over several spans of RC beams.

Simply Supported Beam Steel

• For single spans, the main reinforcement steel is bottom steel.

Joint Types for Precast Concrete

• Wet joints (Monolithic joints) using in-situ concrete topping are better for preventing water leakage issues than dry joints (sealant/gasket) due to complete gap coverage.

Silent Construction Equipment

• Hydraulic vibrator machines are notable for quieter operation.

Fire Damage Threshold

• Concrete and steel structures lose half their strength at 600°C.

Wall Tile Moving Machinery

• Material hoists are used for moving wall tiles.

Watertight Joints

• Silicone is best for watertight joints in various construction applications.
• Epoxy is better for concrete spalling or structural repair.

Covering Materials

• Plastic is a common material used for cover spaces in construction.

Curtain Wall Systems

• Unitised systems are the most effective and cost-efficient.

Popular Displacement Pile in Hong Kong

• Steel H Piles are the most prevalent.

Bored Pile Installation

• Bored pile installation requires temporary steel casing, hydraulic oscillators, chisels, RCD with roller bits, underway marks, steel reinforcement cages, and tremie pipes.

Pile Tests

• Common pile tests include dynamic load tests, static load tests, sonic load tests, sonic logging tests, standard penetration tests, core drilling, vibration tests, lateral load tests, and tension tests.

Top-Down Construction Advantages

• Top-down construction minimizes construction time because basement and superstructure can be constructed simultaneously.
• Weather conditions are favorable.

Deep Basement Construction Methods

• For basements exceeding 20 meters in depth, diaphragm walls are preferred in tandem with a top-down construction process.
• Basement construction up to 10–20 meters deep typically utilizes steel sheet piling, and cofferdams.

Basement Building Risks

• Soil collapse, worker safety, underground utility disruption, neighboring structure settlement, and groundwater issues are primary concerns during basement construction.

Precast Concrete Advantages

• Skilled labor demands are lower in precast constructions due to consistent quality control in factory settings.
• Construction costs are potentially lower and environmental aspects are improved.
• Indoor working, using robots, and better compaction are possible.

Precast Construction Considerations

• Window frames are cast before concreting for better water leakage control.
• Waterproofing layers are used within prefabricated sections for improved leakage prevention.

Precast Concrete Construction Benefits in Reducing Labor Demands

• External finishes are fixed at ground level to avoid scaffolds, reducing labor on site.
• Precast construction eliminates separate trades, streamlining site workflow.
• Production operates consistently, irrespective of weather conditions.
• Precast elements ensure timely product supply.
• Construction time is shortened, and labor-related issues are limited.

Precast Production Advantages

• Waste in material use is reduced in factory production.
• Quality of completed work is improved, reducing rework needs and minimizing future repairs.
• Noises, and fumes are confined to factory areas, thus improving the overall environment.
• Replacing timber formwork further enhances the process.

Prefabrication on Site Plan Considerations

• Ensure that the tower crane can handle the necessary materials.
• Provide suitable storage space with appropriate dimensions.
• Decide on the most efficient materials handling system based on the speed and frequency of the consumption of pre-fabricated materials within the construction process.
• Ensure that the internal site access can handle any construction vehicles.

Machine Dug Pile Installation

• Predrilling is essential for pile placement directly unto the rock surface.
• Soil investigation determines the appropriate place for the pile.
• Vibratory hammers or oscillators are used to position and install the casing.
• Rotary augers or other drilling bits are used to bore the initial holes.
• The casing is connected for extension in the drilling process.
• If the pile is founded on rock, RCD (reversed circulation drill) can be used.
• Reinforcement cages, tremie pipes, and concrete are put in place for filling.
• The casing can be removed from the boring hole after sufficient concrete strength.

Diaphragm Wall Procedures

• Guide walls and hydrofraise/hydromill tools create trenches.
• Bentonite slurry helps during excavation because it prevents soil collapse.
• The soil needs recirulation and is pumped from the trench while excavation is ongoing.
• Tubes (stop ends) are used to create a semicircular recess for construction joints.

Top-down Construction Process

• Diaphragm walls are built.
• Bored holes and stanchions are used in the top-down construction approach.
• Ground floor slabs are constructed as the upper portions are exposed and ready.
• After constructing the ground floor, the excavation for subsequent levels can begin, while the building's superstructure is constructed simultaneously.
• Excavation work leads to beam and slab systems supporting the wall.
• Removal of debris is carried out as the process progresses.

Test your knowledge on various aspects of construction engineering, including piles, formwork, concrete additives, and more. This quiz covers important topics such as the Wet Joint method, dewatering operations, and structural materials. Perfect for students and professionals in the field of construction.