Road Construction Methods and Classifications

Road Construction Methods

• Roads link barangays and cities, facilitating transport and communication, boosting economic development.

Road Classifications

• Usage: National, primary, secondary, provincial, city, municipal, barangay roads.
  • National roads are major highways connecting provinces and regions.
  • Secondary roads connect national/provincial roads to stations.
  • Provincial roads link municipalities within a province.
  • City roads are within city limits.
  • Municipal roads are within municipality limits, excluding industrial/commercial areas.
  • Barangay roads are outside poblacion areas.
• Importance: Major roads serve high-traffic areas and major cities. Minor roads primarily serve the locality.
• Surface Course: Earth, gravel, asphalt, concrete.
• Traffic Volume: Heavy, medium, light.

Road Components

• Aggregate sub-base: Natural or excavated soil, compacted during construction.
• Aggregate base: Stabilizing layers on the subgrade, distributing traffic load.
• Surface course: Top layer, providing wear resistance and comfortable skid resistance.
• Drainage structures: Collect, transport, and dispose of surface water, including U/V-shaped ditches and culverts.
• Slope protection/retaining structures: Stabilize slopes, including retaining walls where needed to prevent detrimental erosion.
• Miscellaneous structures: Other works including erosion and sediment controls.

Preparatory Work

• Preconstruction Conference: Contractor and project engineer meet to discuss project details and schedules.
• Temporary facilities: Offices, equipment yards, storage facilities.
• Access and detour roads: Providing alternate routes during construction maintaining safe transport.
• As-stake survey: Actual position of road structure.
• Plans: Documents governing infrastructure.

Road Base Preparation

• Clearing and grubbing: Removing vegetation, trees, and other objects for road construction.
• Removal of existing obstructions: Removing existing structures on construction site (e.g., pavements, water lines).

Roadway Excavation

• Roadway excavation is the process of removing and transporting earth for use in other parts of the project, or for waste disposal.
• Excavation efforts should not disturb material outside designated limits.
• Unsuitable excavation consists of mixtures of saturated/unsaturated soils and organic material unsuitable for foundation material.
• Rock excavation involves removal of igneous, sedimentary or metamorphic rock.
• Unclassified excavation involves removal of other material not classified in the bill of quantities.
• Surplus excavation refers to excavated material used to fill embankment.

Embankment Fill

• Excavated material is compacted into fill.
• Trial runs are conducted to confirm suitable compaction.

Stabilizing Layers

• Subbase course: Layer beneath the surface course to alleviate compressive stress.
• Base course: Layer beneath the surface course to distribute load and prevent pumping.

Concrete Pavements (PCCP)

• Purpose: Provide a smooth, long-lasting, and clean surface.
• Terminology: Workability, consistency, water-cement ratio, admixtures, curing agents.
• Types of joints: Construction, contraction, expansion, load-transfer devices (dowels/tie bars).
• Methodology: Form setting, concrete mixing, pouring, finishing, curing, and de-moulding.

Batching and Pouring of Concrete

• Concrete batching plants ensure consistent concrete mix delivery.
• Proper concrete placement ensures prevention of segregation.
• The use of concrete vibrators is essential to aggregate uniformity and voids.

Concrete Finishing

• Methods and tools for finishing include floating and brooming to give concrete a smooth surface.
• Proper curing is crucial to prevent the loss of moisture to properly maintain strength and durability.

Pavement Protection

• Protection from rain and traffic is essential if freshly laid concrete is not to get damaged.

Slope Protection/Retaining Structures

• Purpose: Protect slopes from erosion, accommodate space constraints.
• Types: Grouted riprap, stone masonry, gabions, reinforced concrete.
• Methodology: Excavation of foundations, layering of stones/boulders, placing of grout.

Miscellaneous Structures

• Guardrails: Define safe roadway limits, protect motorists and pedestrians.
• Curbs and gutters: Define the boundaries of the road, collect surface water.
• Road signs: Provide information and guidance to drivers.

Explore the various methods and classifications used in road construction. Learn about different road types, their usage, surface materials, and traffic volumes. This quiz covers essential knowledge for understanding how roads facilitate transport and economic development.