ARCH 133 Module 1: The Building

ARCH 133: Building Construction III - Concrete and Steel Construction

• This module focuses on building construction, specifically concrete and steel construction.

Modules Overview

• Topics include the building, concrete & steel, foundation systems and floor systems.

Module 1: The Building

• This module covers building systems, building loads, lateral stability, and high-rise structures.

Definition of a Building

• A building is defined as a structure with a roof and walls, meant for uses such as housing, education, commerce, or industry.
• "Building" can also refer to the process or business of constructing something.

Other definitions

• Dams, canals, bridges, tunnels, and aqueducts are considered to be buildings

Building Systems Notes

• Architecture and building construction are distinct but related fields.
• Understanding how to assemble materials, elements, and components is crucial during the design and construction phases.

Conceptual Systems

• Interior spaces characterized by definition, scale, proportion, and organization.
• Ordering human activities by scale and dimension.
• Functional zoning based on purpose and use.
• Access to horizontal and vertical paths with the interior space.
• A building's sensible qualities include considerations of form, space, light, color, texture, and pattern.
• Integration as a functional part of the built and natural environment.

Building Forms

• Function, environment and socio-economics are key considerations.
• Buildings are an "assemblage of compatible components", that are arranged in various ways to create different configurations
• A "system" is defined as "an assembly of interrelated or interdependent parts forming a more complex and unified whole and serving a common purpose".

Building Systems: Structural, Enclosure, and Mechanical

• Structural systems are design to support and safely transmit applied gravity and lateral loads to the found without exceeding stresses.
• Enclosure systems act as a shell, consisting of the roof, exterior walls, windows, and doors.
• Mechanical systems provide essential services to the building.

Structural Systems Explained

• Columns, beams, and load-bearing walls are key in supporting floors and roof structures.
• The superstructure is the building's vertical extension above the foundation.
• The substructure is the foundation.

Enclosure Systems Explained

• They include the roof and exterior walls
• Doors provide physical access.
• Windows provide access to light, air, and views.
• Interior walls/partitions subdivide the interior into spatial units.

Mechanical Systems Explained

• Provides essential services by providing the following:
• Water supply for consumption and sanitation
• Sewage disposal for waste removal
• HVAC for environmental comfort
• Electrical power for lighting, security, communication, and automation
• Vertical transportation for moving people and goods
• Firefighting systems to detect and extinguish fires
• Structures may also require waste disposal and recycling systems.

Uniformat II

• Uniformat II is a classification system for building elements used for specifications, cost estimating, and analysis.
• Level 1: Major Group Elements (Substructure, Shell, Interiors, Services, Equipment & Furnishings, Special Construction & Demolition).

Performance Requirements

• Buildings must comply with legal standards, which must include that all listed conform to the following:
• Structural compatibility, integration, and safety.
• Fire resistance, prevention, and safety.
• Acceptable thickness of construction assemblies.
• Controls of heat and airflow from assemblies.
• Controls of water vapor condensation
• Accommodation of movement due to settlement, structural deflection, and expansion.
• Noise reduction, sound isolation, and acoustical privacy.
• Resistance to wear, corrosion, and weathering.
• Finish, cleanliness, and maintenance requirements.
• Safety in use.

NBCP (National Building Code of the Philippines) - Types of Construction

• Type I: Wood construction
• Type II: Wood construction with fire-resistant materials (1-hour fire resistance)
• Type III: Masonry and wood construction
• Type IV: Steel, iron, or concrete (walls, ceiling, and partitions fire-resistive and incombustible, some treated wood allowed in framing)
• Type V: Four-hour fire-resistive construction (structural elements of steel, iron, concrete, or masonry)

Building Loads

• Structures must counteract gravity using a balance between the form and the strength of its materials
• Engineering mechanics: Branch of engineering analyzing external force effects on rigid bodies.
• Static and dynamic are two types of loads a building must be able to support.

Engineering Mechanics Branch

• Deals with Statics, the study of external forces on rigid bodies at rest
• Deals with the bodies that contain movement based on the action of forces

Types of Loads

• Dead Load
• Live Load
• Rain/Snow Load
• Wind Load
• Seismic Load
• Thermal Load
• Soil Load
• Hydrostatic Pressure

Dead Load

• It is the static weight of a structure and its permanent, fixed components (beams, columns, floors, roofs, walls, fixtures)
• Deadloads are consistent and are calculated based on material density and geometric factors.

Live Load

• It is temporary or variable weight on structures, such as people, furniture, and the like.
• Live loads are change over time and based on intended occupancy.

Rain/Snow Load

• Relates the weight of water that accumulates on a roof due to rainfall
• Relates the weight of snow that accumulates on structure and is affected by snowfall, the roof slope, snow drift, and the winter conditions of climate.

Wind Load

• The force exerted by wind pressure on a structure
• Acts horizontally or at an angle depending on wind speed, building height, shape, orientation, and exposure

Earthquake Load

• Seismic forces are vibratory ground motions from an earthquake.
• Horizontal components are the most important factor to consider.

Lateral Stability

• Goal of building construction is to create a stable structure.
• "Lateral" means sideways and "force" means momentum over time.
• "Lateral force" therefore means momentum is being changed in a sideways direction.
• Must withstand lateral wind and seismic forces from any direction.

Horizontal Diaphragm, Rigid Frame, Shear Wall & Braced Frame

• Horizontal Diaphragm: In rigid floors, lateral loads are transferred to vertical shear walls, braced frames, or rigid frames, but acting as flay and deep beams.
• Rigid Frame: Relates back to the steel or reinforced concrete frame with rigid joints capable of resisting changes in angular relationships
• Shear Wall: Relates back to the wood, concrete, or masonry wall capable of resisting changes in shape and transferring lateral loads to the ground foundation
• Braced Frame: Includes steel frames with diagonal members.

Knee-Bracing, K-Brace & Cross Bracing

• Knee-bracing, K-brace & cross bracing are all related in such that their stability depends on the use of two members to stabilize lateral forces
• Rigid bracing can be used due to single member stability

Irregular Structures

• Irregular structures characterized by any variations of vertical irregularities in the layout, soft or weak stories or a discontinuity between the sheer walls or diaphragms
• Torsional irregularity refers to resulting non coincident centers of mass and resistance.
• Center of resistance is the centroid of the vertical elements of a lateral force-resisting system, through which the shear reaction to lateral forces acts

Re-entrant corner

• Seismic joints physically separate adjacent building masses
• It tends to causes differential motions between different portions of the structure.

High-Rise Structures

• Tall buildings are susceptible to lateral forces, a rigid frame is the least efficient way to achieve lateral stability.
• Supplementing a rigid frame with mechanisms such as diagonal bracing or a rigid core is necessary.
• An efficient type of said structure is tube structure which has a parameter related force-resisting system that is internally braced by rigid floor diaphragms which acts as a cantilever beam to resist those forces.

Building Heights in the Philippines per NBCP

• Low-Rise: 1-5 stories tall.
• Medium-Rise: 6-15 stories tall.
• High-Rise: 16-60 stories tall.
• Very Tall Building: Taller than 60 stories

Lateral Forces Explained

• A perforated shell tube has perimeter shear walls with less than 30% of the surface area perforated by openings.
• A framed tube has closely spaced perimeter columns rigidly connected by deep spandrel beams.

More high-rise structure info

• A latticed truss tube is known for perimeter frames with closely spaced diagonals with no vertical columns.
• A trussed tube has trussed wall frames of widely spaced columns tied together by diagonal or cross bracing.
• Bundled tubes are modular structures that has narrow tubes to form modular structures with cellular box girder that cantilevers ground.

High-Rise Structure Facts cont.

• A braced tube is a framed structure tied to each other by diagonal braces.
• A tuned mass damper is a heavy mass mounted on rollers and attached to the upper portion of a tall building with spring damping mechanisms to dissipate building movements.
• A tube-in-tube structure has an inner braced core added to the perimeter tube to improve shear stiffness when resisting forces.