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• Design and construction have four phases: pre-design, design, pre-construction, and construction.

Pre-Design Phase

• Setting objectives and planning criteria is key
• Begins after the owner identifies the design firm or consultants
• A feasibility study might be completed
• The owner & consultant decide the goals & objectives
• Identifying needs and constraints is part of the process
• Includes title search and zoning analysis, site search & selection, financial planning, scheduling, and programming

Design Phase

• Geometry, materials, and performance of structure are determined

Pre-Construction Phase

• Involves selecting project participants and outlining contractual agreements
• Activities involve getting building permits, selecting project participants, and signing agreements
• GC establishes a field office, does subsurface investigation, also site preparation
• Dewatering, shoring, underpinning and earthwork is part of the process
• Installing utility infrastructure; site improvements like access roads and walks are included
• Arrange access for deliveries and equipment
• Designate space to storage and staging of materials
• Designate space to sorting and storage of construction waste materials
• A pre-construction conference should be arranged that includes the owner, general contractor (GC), construction manager, and subcontractors

Construction Phase

• A finished building is physically constructed

Construction Industry Divisions

• Building construction includes residential, commercial, civic, educational, religious, and agricultural projects
• Heavy construction includes highways, bridges, canals, dams, subways, tunnels, utility piping, water control, and communication projects
• Industrial construction involves buildings for large scale manufacturing & processing plants or utility generation installation

Main Players

• Owner- Initiates project
• Architect and engineers- Design the building
• General contractor- Completes actual construction

Support Players

• Consultants: offer professional services to the main team
• Subcontractors perform portions of work under GC
• Product representative assists with submittals and furnishes field services
• Manufacturers produce materials or products
• Testing labs & inspection agencies offer quality control services

Orthographic Drawings

• Floor plan: Image of a building, looked down upon after an imaginary horizontal cut, footprint
• Building section: View of a building after a vertical plane has been cut through it
• Elevation: View of the exterior facade, delineating geometries and material

Shop Drawings

• Give precise directions for certain components, suich as steelwork and concrete

Site Assessment

• Site assessment performed before the start of construction
• Ensures efficient design and construction
• Involves land and topographic surveys, subsurface soil testing, and environmental studies

Site Plan

• A detailed drawing of a planned site development
• Prepared by licensed architect, engineer, or surveyor
• Illustrates locations, dimensions, floor elevations of structures
• Site entrance & exits, drives, fire & service lanes are listed
• Shows parking & loading areas and pedestrian walkways
• Displays existing & proposed underground & overhead utilities, grades
• Marks locations of public or private site lighting and fire hydrant
• Displays existing contours & proposed changes to help verify drainage

Site Work Activities

• Includes many activities such as: erosion control, demolition, earthwork, and site remediation
• Addresses foundations with spread footings, piles, and caissons
• Can address wet enviroments that require dredging, underwater work, & constructing seawalls, jetties, docks
• Requires setting uo Utility trenches for water, sewer, gas, oil, steam distribution
• Involves construction of ponds, drainage reservoirs and sewage lagoons
• Requires putting in of Walks, fences, irrigation systems, & landscaping

Site Work Considerations

• Conservation of natural features
• Preventing the escape of pollutants
• Restoration of damaged areas
• Containing site disturbances
• Protecting & restoring existing vegetation
• Properly stockpiling and protecting stripped topsoil for reuse
• Prohibit the discharge of toxic waste materials
• Acknowledge of flood zones

Sedimentation and Erosion Control

• Storm water transports dirt & contaminants from construction site
• Erosion & sedimentation problems should be controlled
• Civil engineer identifies areas prone to erosion & suggests strategies for soil stabilization
• Utilize temporary erosion and sedimentation control measures like temporary seeding, mulch barriers, earth berms, silt fencing and sediment traps
• Permanent plantings, fast-growing grasses
• Placement of earthen swales (depression) to divert runoff water into temporary sediment basins

Stormwater Drainage

• Remov water from a development
• Important to do both during and after construction
• Prevents water damage to basements and surfaces
• A topographic map should be used
• Surface drainage systems can include ditches, swales, detention basins
• Subsurface drainage can use drainpipes (concrete, PVC) leading to storm-water system

Demolition

• Breakdown & removal of existing structures
• Includes buildings, roadways, parking areas, and submerged tanks, utility lines
• Involves removal of hazardous materials (asbestos)
• Site clearing is removal of trees and other vegetations
• Grubbing is removal of subsurface obstructions (roots, stumps, etc.)

Site Remediation

• Involves activities that benefit the building site in the long-term
• Generating productive soils
• Restoring natural habitats
• Removing toxic substances
• Preventing erosion

Earthwork

• Relates to soil excavation, transportation, and relocation
• Activities include: grading & excavating, backfilling & compacting, laying base courses
• Stabilizing the soil, setting up slope protection, and establishing erosion control

Grading

• Changing the landform of a site using heavy equipment
• Leveling the area for building/structures
• Creating movement paths
• Establishing drainage and landscape features
• Rough grading levels the ground for excavation and building
• Some equipment to use is grader, front-end loader and backhoe
• Topsoil should be preserved
• A level plane can be accomplished by cutting (removing soil), filling (importing), or cut and fill (balances)

Excavation

• Excavation depth depends on the type of soil
• A sloped side can be used for shallow work
• Bench system can be used for a deep excavation

Sheeting

• A method of supporting soils from caving in
• Done in the form of sheet piling, lagging, and slurry walls
• Sheet pile may be wood, aluminum, steel, vinyl, or precast concrete placed vertically into the ground
• Vertical steel columns (soldier piles) driven into the soil and horizontal wood lagging, it contains excavations.
• Steel sheet piling uses interlocking steel sheets are driven or vibrated into the earth before excavation
• Uses cross-lot bracings which are supported steel posts

Tiebacks

• Secures sheet pile on a wide construction site to avoid obstructions
• Option 1 - on a firm soil/rock: a steel cable is inserted, the hole is filled, the cable is tightened
• Option 2 - on a loose soil: usea a screw anchor

Slurry Wall

• A cast-in-place concrete method protects, becomes foundation
• Excavation is dug with a clamshell bucket, filled with slurry of bentonite clay & water
• Welded steel is lowered into the cavity, concrete is poured and excavation can begin

Soil Anchor

• Metal grouted shafts stabilize excavation sides
• Drill holes, fill the hole with grout
• Push reinforced steel bar

Cofferdam

• Temporary watertight enclosures for use in water or water-bearing soil
• Prevents water from construction
• Using sheet piling or a double-wall structure extend down to bedrock

Caisson

• A watertight shell for carrying out construction below water level
• May be open or pneumatic
• Open caisson is exposed to the weather, work is performed under pressure
• Pneumatic caisson is air and watertight
• To keep excavation clear and free of water, the process requires pressurized air

Underpinning

• Supports existing building when construction happens nearby
• The use of trenches occurs at intervals and filled to support
• Needles are heavy wooden timbers or steel beams, spacing is a factor

Paving

• Surfacing for vehicular or pedestrian traffic use
• Common materials: Portland, asphalt concrete, stabilized soil and gravel
• Flexible Layers uses Compacted subgrade, provides additional support
• Includes high quality materials with bitumen for base and wearing surface
• Rigid layers are compated and have reinforced concrete

Building Elements

• Superstructure above the ground
• Substructure below grade
• Foundation supports

Foundation Classification

• Shallow is pad or strip footing
• Deep uses piles and shafts
• Load transfer happens via spreading
• Loads bearing can be transfered via driven or drilled pile foundation

Foundation Choice

• Dependent on Type and size of the building
• Also includes soil and subsurface water conditions
• Based on Building code requirements
• Placed below frost line to prevent freeze-thaw
• Spread footing transmits loads to the soil
• Strip footing is around the perimeter
• A Combined footing shares columns for support

Slab Grade

• Reinforced concrete slab placed directly on the ground for support with thick edes
• Minimum of 4 inches
• Constructed as an extension of a stem wall
• Construction involves compacting the ground and applying a gravel bed
• Reinforce with steel or mesh