Building Construction Homework 1 PDF

Selena Wang ARC 415K 10/03/2024’ Building construction illustrated Construction HW 1. Sketch and label, either in section or axonometric, the system most likely used to build the rammed-earth wall depicted in the image above. What is the name of this method of forming walls? (6 points) ​ Slip...

Selena Wang ARC 415K 10/03/2024’ Building construction illustrated Construction HW 1. Sketch and label, either in section or axonometric, the system most likely used to build the rammed-earth wall depicted in the image above. What is the name of this method of forming walls? (6 points) ​ Slip-forming construction ​ Rammed earth is a mixture of clay, silt, sand, and water that is compressed and dried to form as wall construction. The mud is formed into blocks using wooden (or metal) forms). A damp soil mixture is compacted by hand or mechanically in layers no more than 6” before the next is placed, bonding to the previous. 2. What is “stabilized adobe”? Explain what it means in terms of the material composition. (3 points) Mention one advantage and one disadvantage of using it? (3 points) ​ An admixture of of portland cement and other chemical compounds allows adobe to be left exposed. ○​ Advantages: Increases strength, limits water absorption= adobe can be left exposed. ○​ Disadvantages: once stabilized with Portland cement it becomes closer to concrete in terms of high embodied energy, and no longer maintains net zero carbon emmisons. 3. The stone walls depicted below were built using two different methods. Name the two stone-laying methods and describe each process. (3 points) Mention one advantage and one disadvantage of each of them. (3 points)  ​ (LEFT) Wet-laid stone wall- uses mortar as a binding agent (like brick). Usually, it is meant to be finished with the face of another stone, stucco, or plaster ○​ Advantage: Mostly impermeable because it is sealed with mortar. ○​ Disadvantage: Needs a drainage system through weep holes in addition to the wall, to prevent moisture build-up and allow water to escape. Cracks along mortar joints ​ (RIGHT) Dry stacked stone- Does not use mortar as a binding agent. It relies on gravity and balance to hold the stones. naturally occurring stone which lies at/near the surface ○​ Advantage: It can be used in its natural form/carved. It can drain and ventilate naturally. ○​ Disadvantage: It attracts insects, lizards, and small animals. It does not keep water out 4. Renzo Piano used a local type of sedimentary stone in the Valletta City Gate in Malta (pictured below). Speculate about how the stone blocks were attached to the façade. Mention the name of this cladding system and sketch it in a section or axonometric. (6 points) ​ A rain-screen cladding system was used causing a physical separation between the outside of the facade and its interior wall, which allows for ventilation preventing humidity. ​ The stone blocks were anchored using metal fixings/anchors. ​ There is an outer layer of cladding/screen( which sheds most of the rain), an air cavity(drains water that may penetrate the outer layer and reach the support wall), and a drainage plane on a water resistant, airtight support wall 5. Discuss one aspect of bamboo construction that requires particular attention to ensure structural stability and longevity of the structure. You can refer to the lecture slides but you should also consult the provided manual. (3 points) ​ Because bamboo is prone to humidity, fungus, lichens, and insects, cutting and drying the bamboo is imperative to ensure its durability, longevity, and structural stability. ○​ Some ways of protection include immersion, injection, and pressure using borax salts. Nonchemical treatments include temperature steaming- which is more expensive and less common. ○​ Vertical sap diffusion- putting canes with branches and leaves in a vertical position in a container ​ Bundling bamboo into culms is also an aspect of bamboo construction that ensures structural stability. Bamboo has high resistance to tension and is lightweight and flexible, absorbing energy. It performs well in seismic zones. ​ Joint connection to the ground, must be removed from ground in some way 6. Name and describe the difference between the two main straw-bale construction methods. (3 points) ​ Load Bearing- There is no structural frame and the roof is supported by bales that resist lateral loads ○​ Height is usually 1 story ○​ Requires little skill, cheaper, less flexible, and harder to permit ​ Non-Load Bearing- The straw bales are used as an infill and insulation in a structural system (timber frame), straw isn’t structural ○​ Requires more skill, is more expensive, flexible, and easier to permit 7. The structure of the building depicted below, VTN Architects used bundled bamboo to form structural elements. Think of one advantage of bundling of slender elements as opposed to using one thicker culm. (3 points) ​ A more slender culm of bamboo allows for more flexibility within the structure. It also allows for loads to be distributed more evenly and for it to bend and absorb stress without breaking compared to a single thicker column. Decrease risk of snapping. If one is under stress others keep it together, enough time to see it and swap out 8. Describe the relationship between the amount of water in a concrete mix and the strength and workability of the material. (3 points) ​ Concrete is a 1:2:3 ratio mix of cement, sand, and coarse aggregates. The amount of water to the compressive strength of concrete is inversely proportional. ○​ As water increases, the workability of the concrete increases, but the strength decreases. ​ Hydraulic Settling= when water causes the cement to set and bind ○​ 9. Briefly describe what an admixture is. Provide one example of how its use might be beneficial in a concrete mixture. (3 points) ​ Admixtures are added to alter the properties of the final product/workability of the mix such as water-reducing agents which reduce the amount of water needed to make concrete workable; this happens by dispersing cement particles. 10. What is the function of steel bars in reinforced concrete? (3 points) Why do they have to be protected from exposure to air and water? (3 points) Sketch the pattern of steel bars in a beam and name 4 main elements. (6 points) ​ Reinforced steel bars are needed because concrete is weak in tension. They absorb tensile and shearing stress. This distribution of forces also helps with crack control. Steel rusts and corrodes when exposed to moisture and oxygen. This corrosion causes the steel to expand and weaken the structural bond between the steel and concrete, causing it to crack. 11. Sketch and label, either in section or axonometric, the wood formwork system that could have been used to cast a wall like the one seen in the picture below. (6 points) Woodwork form 12. Different brick grades designate durability when exposed to weathering in a particular climatic region. List the three grades of brick and describe the appropriate applications for each. (3 points) ​ Severe weathering- For subfreezing temperatures where freezing and thawing occurs ○​ Used on exterior walls and foundations with direct contact ​ Moderate Weather- For moderate climates where occasional exposure to freezing occur ○​ Used on exterior walls ​ Neglibible Weathering- For minimal exposure to weather and moisture ○​ Used in interior spaces 13. Mortar, grout, and concrete have the same principal constituents (cement mix, sand, gravel, water), but they have different mix proportions, properties, and functions, and are governed by different standards. Which one is NOT used in masonry above grade? What is the function of each of the other two mixes when used to bind masonry units? (3 points) ​ Concrete is not used in masonry above grade. Mortar is a bonding agents used to hold bricks while grout is used to consolidate the wythes/vertical sections of the walls. 14. A double-wythe brick wall has to be bonded with more than just the mortar. Sketch and label two ways in which two wythes can be bonded together. (6 points) ​ Can be reinforced with steel bars placed in a cavity filled with grout ○​ Metal ties connect wythes to mortar joints ​ Header bricks lay perpendicular to the face of the walls spanning both wythes, tying them together 15. What is a lintel? (3 points) Name 3 common types, and sketch and label one of them. (6 points) ​ A lintel is a structural horizontal element that spans the opening between two vertical supports ○​ Steel Angle Lintel ○​ Reinforced Brick Lintel ○​ Concrete Masonry Lintel 16. What does the term “anisotropic” mean and how does this characteristic affect the qualities of wood? (3 points) ​ Anisotropic means a material's physical properties vary depending on the grain direction in which it is cut ​ Parallel & Perpendicular to grain ​ Tensile and compressive forces are best handled parallel to the grain 17. How lumber is cut from a log affects its strength and appearance. Sketch a plainsawn and a quartersawn board in the top view and section. (3 points) Explain how they differ in performance. (3 points) ​ Plainsawn logs are cut in parallel planes  ○​ It tends to swell, shrink, cup, and twist due to uneven shrinkage ○​ There is more movement along the tangential plane of growth rings which are parallel to the face of the board, as wood dries, it shrinks unevenly ○​ Used when grain pattern is desired for construction ​ Quartersawn logs are cutting quadrants in the diagonal direction ○​ Less likely to swell, shrink cup, and twist, offer more stability over time ○​ Growth rings are perpendicular to the board surface, wood shrinks and expands more evenly ○​ Used when stability is critical 18. Platform framing is the most common form of light wood frame residential construction nowadays. What is the other (rarely used) framing method? (3 points) Sketch and label the two systems in axonometric focusing on how studs relate to plates in a typical wall assembly in each of these methods. (6 points) What is one reason why platform framing is considered safer and the other system is no longer used? (3 points) ​ Balloon frames is rarely used anymore, despite being very popular in the past. Platform Framing is much more fire resistant compared to balloon framing as there is a platform between each floor that acts as a barrier. ○​ Platform framing- constricted each floor at a time, instead of all at the same time. The studs span floor to floor as opposed to the entirety of its height. Chiminey that draws fire and heat through the walls- fansis pg 197 19. Explain the main difference between wrought iron, steel, and cast iron considering the content of carbon, material properties, and workability. (3 points) Explain how the amount of carbon affects the properties of these materials. (3 points) Mention one project in which each material was used. (3 points). ​ Types: ○​ Wrough Iron has 0.1% carbon. It is soft, ductile malleable, and easy to work with and prefabricate. ​ Ex. The Eiffel Tower (Paris)- prefabricated parts were riveted on site ○​ Steel has 0.15%-2% carbon. It is relatively soft, ductile, and malleable, and is strong in tension and compression. ​ Ex. The Reliance Building (Chicago)- first steel frame building, which had large plates of glass and cladded with terracotta​ ○​ Cast Iron has 2%-4.5% carbon. It is brittle, hard, nonmallerable, and strong and compression. It has a low tensil strength compared to wrought iron and steel. ​ Ex. The Crystal Palace (London)- prefabricated off-site, easily bendable/malleable ​ The amount of carbon can highly affect the strength of the steel. More carbon leads to more strength and hardness, but it also leads to a decrease in malleability and workability. 20. In the photograph below, the Eames are standing on a structural steel beam during the construction of their Case Study House No.8 (Los Angeles, CA, 1949). Name the other horizontal structural element that you see in the image. What are its main characteristics comparing to the structural beam? (3 points) ​ Open web roof joists are also present ○​ The open web joist is a lightweight, prefabricated steel member that includes trussed webs ○​ Compared to a solid structural beam, the open web joist provided equal support with less material, making it much lighter and they require less support to span long distances. ○​ Limited in over hang potential ○​ Span longer dist with less material 21. In the essay entitled “Materials ad Infinitum,” Billie Faircloth observes: Anyone wanting to use material evidence - to accrete materials knowledge for the purposeful assembly of bits into wholes - should recognize that both construction logic and material origin are legitimate sources (55).Discuss what Faircloth means by “material origin” as a “legitimate source” and how “material origin” differs from “construction logic” as a source of knowledge for the purpose of advancing construction methods. Support the discussion with an example. (6 points ​ Construction logic is the technical system in which a material is assigned to a structure, as well as its arrangement. When we think about construction materials through only a construction logic, people forget with commercialization the raw form of the material such as with lumber eventually being known as the 2x4. Construction logic refers to the wood as strong and good in compression, while material origin is a source that refers to it as renewable, but not always sustainable. We need to think about material origins and construction logic in tandumn and analyze whether the material is being used to its capacity. 22. Choose one project that you learned about during the lectures (provide its name and architect if you (remember it). Describe the main materials, construction logics, types of connections, and sketch a chosen detail (9 points). ​ One of the most captivating buildings I’ve learned about this semester is the Maison Hermes store in Tokyo Japan designed by Renzo Piano. The use and custom manufacturing of translucent, hollow glass blocks captivated me. The block is connected by fusing two halves, leaving a partial vacuum. Like brick the blocks are laid in mortar and can be manipulated to create a curved facade along the structure, determining the minimum radius of these curves. Curves are created with curved blocks of different sizes. The 17”x17” blocks are truly unique at its scale. The rigid structure is supported by framing and reinforcing the blocks within a steel frame. The elements between the structure and screen absorb stress and flexibility during earthquakes. ​ The glass blocks are attached to a gridded steel frame with connectors that allows for slight movement in the event of an earthquake, handling tension and compression. Further, the frame is connected to the concrete core of the structure with steel joints, ensuring that stress is distributed evenly. ​ Building blocks ○​ Dimensional lumber sized by nominal dimensions ○​ What is nominal what is actual ○​ Lumber sawn piece of wood ○​ How dimensional lumber pieces can be formed into bigger buil;ding blocks (clt easier to use, much harder to recycle)- the smile ○​ Diff ways glass formed ○​ Diff types of stone ​ Rammed earth and adobe ○​ Uses sundried clay, not fired in kiln, used in place with little rainfall ○​ Platered walls bc bricks shrink and swell, need to be protected to prevent (mud->stucco) ○​ Stabilized adobe- admixture of portland cement, limits water absorption makes it more structural ○​ Lintel does not suppor well in tension to span openings; also in concrete ○​ Environmental impact= 0 carbon emissions if not portland cement ○​ Rammed earth ​ Serves as thermal mass, materials sourced locally, like adobe can be stabilized ○​ Slip form ​ Brick ○​ Used to be heat hardend but now fired, now are extruded ○​ Characterized by modularity, uses mortar as binidng agent, effective in compression, should be laid up in way where entire acts as entity ○​ Use diff things to support brick ​ Wyth made of many courses of brick vs course ○​ Bind patterns ​ Running, flemish, stacked ​ Walls can be reinforced with steel bars or grout= in crease structural capacity ​ Concrete masonry units- hollowblocks, molds ​ Frame and infill as opposed to using building blocks as structural material ​ Having lintel span openings ​ Solid walls vs porous visual screen ​ Diff types of lintels ​ Strength concrete bricks have in compression not tension ​ Stone ○​ General info0 fireresistant, non renewable, in place of rainscreen, naturally occuring mineral ​ 3types of stone by region ○​ What are diff types of stone and properties of each ○​ Dry stakcked vs wet laid ○​ Environmental performance and impact- can be reused if frystacked, recycled ​ Concrete ○​ Understand ingredients, diff affregates can be stone gravel larger than certain size ○​ Prop of concrete- compression, need steel for tension ○​ Can be formed into diff formwork, methods people use ○​ Why steel used to reinforce, common form of reinforcement (rebarb, steel wire) ○​ Concret cna take any form jthrough concrete ,__ or, __- site cast use formwork to cast on site ○​ Think about diff eelemetns that fo into formworks: tieholes, surfacing, how concret can be applied with hose (sprayed) ​ Bamboo and straw ○​ Where materials come from, general properties ○​ Types of construction- load bearing vs non load bearing, diff requirements ○​ Bamboo is grass grows rlly fas ○​ How it needs to be protected from humidity- emmerskon, injection, pressure ○​ Bamboo strength high resistance to tension, elasticity ○​ Used in curved geometries ○​ Most important is formation of joints that ranspere forces from one elemnt to another\ ○​ Joined diff bc hollow, unlike wood ○​ Timber made up of fibers, softwood andh hardwood  ○​ Strength in diff direction ○​ Cut diff behaves fiff ○​ Products- sawn to glulam and clt ○​ \log construction ○​ Heavy vs light timber wood framing; platform vs balloon ○​ Think about assembly oif timber in constrruction as whole, use prefabtricated panels aas walls, ○​ Mass timber- use built up elements (glulam clt) ○​ Heavy timber is trees vut into 8x8 or larger than 2x4 ○​ Clt board form construction panels ○​ Diff construction systems ​ Glass ○​ Rigid without crystal, strong compression, weak tension ○​ Sep structure use as infil for ○​ Products- insulation, fibers, comes in sheets ○​ 100% recyclable ○​ Fkat glazing glass ○​ Annealed or heat strengthened ○​ Opacoty, translucent vs transparents ○​ Light transmiteance- controlled though tinted and caring ○​ Illuminace0 degree visible light transmitted ○​ Luminance- amount light refledct/emmit ○​ Heat gained, reflect absorb tranmsmit radiation ○​ Fisher house- interior of spce, how can glass change quality of interior spaces ○​ Other way glass can be use - blockas ○​ Use mortar between glass blocks as bunding agent ○​ Typically reinforced ○​ Climate appropriate? ​ Metal ○​ Strong in compression and tension ○​ Properties- malleable and ductile (withsand compression; ductile= withstand tensile stress when stretched into wire) ○​ Diff properites and metals ○​ Diff propterites based on carbon content- diff shapes ○​ Can be hot or cold rolled’ ○​ Common assemblies ○​ Structural steel frames ○​ Connections: bolted,welded, etc- affect result and cost ○​ connectioms - simple, loading ○​ Used in larger applications, diff cultural centers, it is also hidden away like timber framing, alternative to lightwood frame ​ Self drilling,s elf tapping screws, bikted, wekded ○​ Space frame- rigid triangulated; space frames 3d ○​ Supported by column or walls, formed into diff shapes not just flat  ○​ Cervantes theatre- light gauge or steel structural framing, uses steel panels, take note of construction and how it was built -​ Take look at case studies, videos on how material is used, put in bold