Week 4: Chapter 3- Structural Systems

 Chapter 3

Structural Systems 

In Chapter 3 we learned about a building's basic structural system and how they work. we also learned about our role as designers in the structural aspect of a building. It was an interesting chapter because we had already learned most of this in Construction but it was cool to see it from more of an interior designer's perspective. 

Chapter notes:

Interior design is a distinct profession with specialized knowledge applied to the planning and design of interior environments that promote health, safety, and welfare while supporting and enhancing the human experience. Founded upon design and human behavior theories and research, interior designers apply evidence-based methodologies to identify, analyze, and synthesize information in generating holistic, technical, creative, and contextually appropriate design solutions.

Interior design includes a scope of services which may include any or all of the following tasks:

• Project Management: Management of project budget, contracts, schedule, consultants, staffing, resources, and general business practices. Establish contractually independent relationships to coordinate with, and/or hire allied design professionals and consultants.
• Project Goals: Understand, document, and confirm the client’s and stakeholders’ goals and objectives, including design outcomes, space needs, project budget, and needs for specific or measurable outcomes.
• Data Collection: Collect data from client and stakeholders by engaging in programming, surveys, focus groups, charrette exercises, and benchmarking to maximize design outcomes and occupant satisfaction.
• Existing Conditions: Evaluate, assess, and document existing conditions of interior environments.
• Conceptualization: Application of creative and innovative thinking that interprets collected project data and translates a unique image or abstract idea as a design concept, the foundation of a design solution. The concept is then described using visualization and communication strategies.
• Selections and Materiality: Selection of interior building products, materials, and finishes; furniture, furnishings, equipment, and casework; signage; window treat­ments, and other nonstructural/non-seismic interior elements, components, and assemblies. Selections shall be made based on client and occupant needs, project budget, maintenance and cleaning requirements, lifecycle performance, sustaina­ble attributes, environmental impact, installation methods, and code compliance.
• Documentation: Develop contract documents for the purposes of communicating design intent and obtaining a building permit, as allowed by law. Documentation by phases may include schematic, design development, and construction drawings and specifications. Drawings may consist of floor plans, partition plans, reflected ceiling plans, and finish plans; furniture, furnishings, and equipment plans; wayfinding and signage plans; code plans; coordination plans; and elevations, sections, schedules, and details illustrating the design of non-load-bearing/non-seismic interior construction and/or alterations.
• Coordination: Overseeing nonstructural/non-seismic interior design scope in concert with the scope of allied design professionals and consultants, including, but not limited to, the work of architects, mechanical, electrical, plumbing, and fire-protection engineers and designers, and acoustical, audio-visual, low- voltage, food service, sustainability, security, technology, and other specialty consultants. Coordination can include, but is not limited to:
• Placement, style and finish of mechanical, electrical, plumbing, and fire-­protection devices, fixtures, and appurtenances (i.e., accessories) with the design of the interior environment.
• Ceiling materials and heights; interior partition locations.
• Acoustical appropriateness of spatial arrangements, construction, and finish materials.
• Working closely with contractors to respect budgetary constraints and contribute to value engineering efforts.
• Contract Administration: Administration of the contract as the owner’s agent, including the distribution and analysis of construction bids, construction administration, review of contractor payment applications, review of shop drawings and submittals, field observation, punch list reports, and project closeout.
• Pre-Design and/or Post-Design Services: Tasks intended to measure success of the design solution by implementing various means of data collection, which may include occupant surveys, focus groups, walkthroughs, or stakeholder meetings. Collection and reporting findings can range from casually to scientifically gathered, depending on the projects scope and goals. 
  

As part of a service profession, interior designers’ success depends on their ability to satisfy clients. Thus, they must possess three important skill sets: creative and technical skills, interpersonal skills, and management skills.

• Creative and Technical: Interior designers must be able to translate a client’s goals into a functional and attractive interior environment that supports the behaviors of the occupants. Successful interior design solutions respond to and coordinate with the building shell, protect the health and safety of the occupants, incorporate building codes, and include many other technical aspects. Attractive interior design solutions layer in the elements and principles of design, leveraging materials, lighting, and furniture to shape the experience of the space. Interior designers follow a systematic process to achieve design solutions.
• Interpersonal: Interior designers must be comfortable meeting and collaborating with many kinds of people. Effective written, verbal, and visual communication skills are necessary to successfully work with clients, stakeholders, and collaborators. Because interior designers frequently work collaboratively with architects, contractors, and other service providers, designers need to be both good team leaders and good team players. They must be willing to negotiate and mediate when necessary to resolve problems
• Management: Interior designers must have excellent time and project management skills, since they frequently work on more than one project at a time, under demanding deadlines, while looking for new projects or clients. They must be able to develop and execute business plans in order to protect and grow their practices. They need to know how to market themselves to clients, to create informative and persuasive proposals and presentations, and to maintain good client relationships.

Purpose of Structural Systems

• Although interior designers do not design structural systems, they need to understand what they are and how they work.
• the main purpose of a structural system is to carry the loads of a building and transfer them to the foundation which in turn transfers them to the ground. The way in which this takes place depends on the type of structural system. 
• three primary types: bearing wall, structural frame, and stud wall systems
• Bearing wall construction relies on the entire wall to carry all loads to the foundation beneath. When an opening is made in a bearing wall, a steel, concrete, stone, or brick lintel or arch is needed to carry the load of the wall above the opening. Bearing walls are most frequently constructed of concrete, stone, brick, or concrete block.

• The stud wall system relies on several small members to carry loads to a horizontal sole plate that in turn distributes the weight to a sill plate. Both light gauge steel and light frame wood construction use stud wall systems.

• The structural frame system is composed of columns and beams that transmit loads to the foundation. Heavy timber, structural steel, or pre-cast concrete can be used to create a structural frame.

Structural Basics

• The four primary characteristics of a structural system are:
• Stability
• Strength and stiffness
• Economy
• Aesthetics
• The stability of a structure describes the state when the forces are equal to zero. The strength of a structure is based on its materials, as is the stiffness.

Loads

• There are several types of loads that act upon a building and to which the structural system must respond. These include live, dead, uniform, concentrated, static, and dynamic loads. 
• Live loads are those loads that move. Examples include people and furnishings within a building.
• Dead loads are those loads associated with gravity and include the building materials and the weight of the building itself.
• A uniform load is distributed evenly. For example, a stone flooring material would be a uniform load on the floor-framing system.
• concentrated load acts on a single point. An extremely heavy safe or piece of equipment would exert a concentrated load. 
• Static loads are those loads that move slowly over time. 
• dynamic loads are Sudden jarring movements exemplified by both earthquakes and wind loads.
• Tensile stress occurs when the building materials are pulled apart under a load. Tensile stress takes place on the underside of the member.
• Compression is what occurs when a building material is compacted together under a load. Compressive stress normally occurs on the top of a structural beam
• Structural design seeks a state of equilibrium wherein all of these stresses are equalized.
• Shear describes the stress that is caused by sliding forces that are moving in two different directions.
• Bending stresses occur when a material is deformed under the weight of a load.

Structural Forms

Cable

Column-and-beam

Trusses

Arch

Shell

A cantenary is a tensile structure consisting of either cable or fabric.

All structure types have advantages and disadvantages

Historic Systems

• Historically, most buildings in the United States were constructed of wood. The first form of wood construction consisted of a column-and-beam system with intermediate wood members. This is also known as a heavy timber frame. Prior to the Civil War, these joints were often mortise and tenon and pegged together.

• Those buildings that were constructed of masonry, such as stone or brick, relied on bearing wall construction. The bricks were handmade on the building site, and stone was quarried locally in most cases. 
• Several bonding patterns were used and helped to date the period of construction. The oldest form of brick bonding used in the US was the English bond. This was followed by Flemish bond and then Common or American bonds such as 3-course, 5-course, or 7-course American bond or Common bond. Running bonds followed once other forms of wall construction replaced true brick-bearing walls.

Systems in Use Today

• wood
• For a variety of reasons, balloon framing was replaced by today’s method of light frame construction: platform framing
•  For platform framing, each floor-level platform supports the walls for that floor. Platform framing can be used for both residential and small commercial projects

• Steel
• As with wood, there are two basic types of steel construction systems: light gauge and structural steel.
• Structural steel consists of a column and beam type system, and light gauge steel incorporates metal studs and metal joists. 

• Masonry and Concrete Bearing Wall Systems
• Masonry consists of a unit member joined together with mortar. 
• Examples of this type of construction include brick, stone, terracotta, and glass block.
• Both the masonry bearing wall and the concrete bearing wall rely on the entire surface to carry loads

Other Systems

• In addition to these traditional structural systems, several new materials have been introduced and some traditional building materials have been reintroduced
• These include structural insulated panels, cob construction, straw-bale construction, adobe construction, rammed-earth construction, and other alternative building methods.
• Structural insulated panels (SIPs) are becoming increasingly popular because they use 30 percent less wood than standard light frame construction. Although they provide no thermal mass, they can be easily assembled on-site and contain integral insulation
• Cob construction uses earth, straw, water, and sand. This hand-mixed material can be formed into a variety of shapes and provides a naturally insulated building using earthen construction. Similar to adobe construction, the earthen walls are self-supporting
• Bales of straw are the primary wall component in straw-bale construction. A wood frame provides the structural framework within which the straw bales are laid like masonry blocks. Oftentimes, bamboo will be used inside the bales of hay to keep them aligned vertically.
• Adobe consists of dirt with added water. Some clay in the soil allows for more stable adobe material. Because of its composition, adobe construction should be protected with deep overhangs and by being lifted off the ground by a foundation. 
• Large, load-bearing walls are used in rammed-earth construction. As a self-supporting material, rammed earth also features excellent insulating qualities
• As the name suggests, cord-wood construction uses “cord” wood, or what appears to be firewood held together with concrete.
• Bamboo framing uses bamboo, a rapidly renewable resource, as a framing system. Similar to light frame construction, multiple members are placed at regular intervals. The canes of bamboo must be joined together such that the structure of the cane itself is not undermined.
• When a building is partially concealed beneath the ground, it uses earth-sheltered construction. This form of construction relies on the constant ground temperature to maintain a constant temperature within the interior.
• Gabion walls consist of a metal cage containing rocks that are approximately 5 to 6 inches in diameter. Although ordinarily used as a retaining wall, this method of construction has also been successfully used in building construction.
• Sandbag walls use stacked sandbags as the primary wall within a timber frame. The sandbags provide excellent thermal insulation and sound absorption as well as keep water from entering the interior. This is a viable option for vernacular construction in parts of Africa and other places with an abundance of sand and local labor.
• Structural biocomposite, developed by Ecovative Design, is a high-performance biomaterial using agricultural waste and fungal mycelium (mushrooms). A structural form of this material can be used in place of engineered wood.
• Fiber-reinforced plastics (FRP) and carbon fibers are both fiber-reinforced polymers. Both are extremely strong, flexible, durable, and stable as well as corrosion-resistant and lightweight
• Insulated concrete forms (ICF) consist of rigid insulation (molded expanded polystyrene) forms held together with either plastic or metal. These are used as formwork for a poured concrete wall. While often used for foundations, they can be used more extensively. They provide high insulation values and are naturally pest-resistant.

Recycled Materials

• Reclaimed lumber, or lumber from old barns and other buildings, has become a recycled new building material for flooring and other applications. Massive timber framing members can be planned into smaller members for use in a new building or renovation project.
• With an increased interest in diverting materials from landfills, other recycled materials being used in both new construction and renovations include concrete masonry units, bricks, stone, tile, and other materials that can be salvaged from demolished buildings
• Additionally, materials such as tires, aluminum cans, and plastic bottles have also been used in alternative construction, primarily on a residential scale. 

Blog Assignment 

SIP (Structural insulated panels) are a building system for residential or small commercial buildings. It uses pre-fabbed panels to create the walls rather than the typical stud construction. the panels consist of insulation foam that is between the interior and exterior sheathing. This system is very strong, energy and time-efficient, and cost-effective. 

https://www.sips.org/what-are-sips