BUILDING CONSTRUCTION II SKELETAL CONSTRUCTION (Temporary Bus Station)
Group Members: Ahmad Ashraf Shefereena Isreen Aimuni Khalidah Caleb Soh CHIN VIN YAN Ang Averllen
0317744 0325915 0326074 0320292 0320311 0321444
INDEX 1. Introduction 2. Design Process a. b. c. d. e.
3. 4. 5. 6. 7.
3 4-9
Design Considerations Idea Development Structural Development Final Design Process
Material Selection Construction Detail Structural Strength Construction Sequence Reference
11 12-14 15-16 17-22 23
INTRODUCTION
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A sound construction of a skeletal structure is proof of a degree of understanding in how the mainframe of a structures’ individual components work together to divide stresses equally under loads and forces. A firm grasp of construction materials and jointing methods for specific tasks and conditions are also needed in order to tie the structure together. We were tasked to create a bus shelter from recyclable materials and appropriate jointing methods for this group assignment. Two shapes are to be picked from a selection of shapes and merged to achieve a form to be built upon. We settled on the cuboid, a stable base to be built or derived from, and the hexagon, whiich when tessellated into a surface provides strong support from lateral/horizontal forces. We worked on wood and acrylic, applying hybrid connections of wood and metal to the superstructures for compatibility with differing materials. Despite having basic construction methods, the complexity of the combination of these methods assures a stable and robust build that will not compromise on quality.
DESIGN PROCESS
4
DESIGN CONSIDERATIONS
INTUITIV E
IMMEDIATE SHELTER
A bus stand should be transparent in terms of usability, having features and layouts that are easy to use and navigate through.
In the event of downpour or other weather extremities, a bus shelter should function as per its namesake. Solid overhead protection and enough space to house a handful of pedestrians should be expected.
STREAMLINE D CIRCULATION
VISIBILITY
To avoid congestion or inefficient bus boarding, a simple circulation through means of transitional spaces or open structures are needed.
Visibility in and out of the bus shelter should be considered to aid in a pedestrians spatial awareness/peripheral view of the oncoming traffic, or a bus driver of pending passengers.
DESIGN PROCESS
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IDEA DEVELOPMENTS Preliminary design of our bus shelter through consideration of structure. Earlier stage of idea being generated through combining two shapes which Hexagon and also Cuboid. The selection of the shapes undergoes deep research about stability in pertinence to wooden structures: Hexagonal frames are scientifically supported to be an efficient packing frame, yielding higher rigidity relative to used up volume. The cuboid as a surface is the most stable mass with a balanced centre of gravity and a wide base area in proportion to height. Consideration of the weather where the bus shelter would be placed as well as the circulation through the bus shelter land traffic direction.
DESIGN PROCESS
6
STRUCTURAL DEVELOPMENT
1.FORM Combined massing in a linear configuration, Hexagonal frames making up the roof, filled in with glass for shelter
2.FORM: Cuboid-mass base, pitched roof connected to base with hexagonal frame wall, planar pitched roof
STRENGTH: Intuitive circulation, ample light allowance WEAKNESS: Irrelevant usage of hexagonal framing in lateral structural rigidity, overuse of columns, lacking lateral reinforcements in exchange for transparency, flat roof
IMPROVEMENTS: Integrated bench system, lateral rigidity, pitched roof allowing for better rainfall circulation, improved use of hexagonal frame, even weight and force distribution through a more uniform base, better allocation of foundation footings
DESIGN PROCESS FINAL DESIGN
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DESIGN PROCESS
8
FINAL DESIGN
Roof plan
Floor plan
DESIGN PROCESS
9
FINAL DESIGN
Front elevation
Side elevation
Rear elevation
CONSTRUCTION PROCESS
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PROCESS
Measuring and marking for cutting purposes.
Nailing method is used to attach the columns and beam.
Materials are cut using electric saw to get a clean finishing.
Mini drill machine is used to make holes on the hard surface.
Wood are cut into small pieces before assembling it into the structural framework.
Constituent parts of roof joist to columns, roof rafters, walls (left to right)
Electric sander is then used to smoothen the surface of the woods.
Final application of roof polycarbonate panel to rafters.
MATERIAL SELECTION
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3mm THICK POLYCARBONATE
Polycarbonate will be used as the roofing covered as it provided shades for the user in the shelter and at the same time sun ray penetrates into it.
TIMBER PLANK
PINE WOOD
In actual model, Glulam timber is used as and columns and roof beams is stronger than other materials. The weight of timber frame structures can be much lighter than steel or reinforced concrete. It also coated with waterproof coatings
In actual model, Gerutu is used for the hexagon shape walls as that wall is one of the main structure for this shelter. Gerutu is suitable for the medium light construction
PLYWOOD CONCRETE
In actual model, teak wood will be used as the flooring as this material will provide the most durability and strength coated with anti scratch coatings.
Concrete Foundation Mixture of cement is poured into wooden formwork to form a rectangular shaped concrete blocks
CONSTRUCTION DETAILS FOUNDATION TO FLOOR
12 Beam to beam
Hexagon to hexagon
Column to foundation
Joist to beam
Timberlinx method
CONSTRUCTION DETAILS
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FLOOR TO WALL/COLUMNS Hexagonal wall to floor
Flooring to column Flooring to beam
CONSTRUCTION DETAILS WALL/COLUMN TO ROOF
14 Roof to truss
Truss to wall cap
Hexagonal wall to wall cap
Side notes: glue is used to indicate this connection
STRUCTURAL STRENGTH
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STRESS & LOAD ZONES
FORCE DISTRIBUTION ON ROOF TRUSSES AND BEAMS
FORCE DISTRIBUTION ON ROOF TO WALLS/COLUMNS
LEGEND ACTIVE LOAD (DEAD/LIVE) DISTRIBUTED LOAD RESOLVED LOAD
FORCE DISTRIBUTION ON HEXAGONAL WALLS
STRUCTURAL STRENGTH
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STRESS & LOAD ZONES
FORCE DISTRIBUTION ON FLOOR JOISTS AND GIRDERS
FORCE DISTRIBUTION ON WALL TO GROUND
LEGEND ACTIVE LOAD (DEAD/LIVE) DISTRIBUTED LOAD RESOLVED LOAD
FORCE DISTRIBUTION ON WALL TO GROUND
CONSTRUCTION SEQUENCE
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METHODICAL ASSEMBLY 6. Wall - Individual hexagons are built modularly.
5. Roof to Wall - The roof beams are attached to the top of the columns.
7. Wall - Wall cap is attached to the top of the hexagonal wall to allow installation of the roof joist
4. Floor - The joist are then attached to the floor beams 8. Wall to Floor - Hexagons are attached to one another, starting from pieces attached to the floor. 3. Column to Floor The beams for the floor frame is attached to the columns.
2. Foundation - Set the floor beam into the strip footing.
1. Foundation - Pad footing is cast with the column set in it.
9. Roof to Wall - Roof trusses are attached in pairs to the roof beam on one side and wall cap on the other.
10, Roof - The polycarbonate sheet is attached to the roof trusses.
CONSTRUCTION SEQUENCE
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PROGRESSION 1. Foundation - Pad footing
Concrete mixture of cement to sand to water (3.5:1.5:1) poured into in situ formwork.
Columns are inserted into the mixture shortly after. Displacement of columns are considered to prevent overspill.
The mixture is left to dry 18 hours before further finishing work is done to avoid irregular settling
END PRODUCT
2. Foundation - Strip Footing
Concrete mixture is done the same and poured into a wooden framework due to volume.
The strip footing is set together with the mixture with further work saved for later.
Mixture left to settle 6 hours longer (24h) due to its mass.
END PRODUCT
CONSTRUCTION SEQUENCE
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PROGRESSION 3. Column to Floor
The main columns to support the roof are nailed directly to the floor beams to aid in transferring the loads outwards.
The end columns are left to border the frame.
The beams leading to the hex wall strip footings are fixed on to the end columns’ perpendicular faces.
END PRODUCT
The floor joists are arranged in a one-way beam system, spanning the length of the structure, connected with nails to the beam frames.
The flanking beams are cut at an angle and are again fixed to the main beams that are to be connected to the foundation systems.
END PRODUCT
4. Floor Beam
Main floor beam that supports the hex wall continues on to form the strip footing. Steel brackets and nails are used to secure the floor beams
CONSTRUCTION SEQUENCE
20
PROGRESSION 5. Roof to Columns
The joist is supported by the three columns that transfer direct load to the foundation and are fixed in place by nails.
Framework of the three columns connected to the roof joist and floor beam.
Roof trusses are measured and set atop the roof cap to the roof joist to form a pitched roof.
END PRODUCT
6. Hexagonal Wall
Modular panels are connected using 60-degree angled brackets to form a hexagon, an element of the wall.
Hexagons are repeated and connected using dowels of half the depth of the wood pieces. Dowels every few angles are inserted to ensure interlocking.
A modular hexagon wall is achieved with the steps repeated several times and arranged deliberately to form the strongest configuration.
END PRODUCT
CONSTRUCTION SEQUENCE
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PROGRESSION 7. Wall to Wall Cap
The ends of the hexagon wall are shaved off at an angle to act as a surface for the placement ot the wall cap.
Angled steel brackets are placed to lock the wall cap to the wall to serve as the main roof girder.
8. Wall to Floor
With the floor decking secured, holes are marked and drilled to insert the brackets to hold the hexagon wall into place.
These angled brackets go through to the floor beams to ensure secure placement of the wall.
The wall cap is angled to position the roof trusses at a pitched angle. This will later serve as the guide for the pitched roof placement.
Screws are inserted once the wall is placed in.
END PRODUCT
END PRODUCT
CONSTRUCTION SEQUENCE
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PROGRESSION 9. Roof Trusses to Wall Cap
Roof truss members are cut and marked on both supporting members.
The trusses are notched to fit the roof joists at an angle to form the pitched roof.
Wood glue is used as a permanent adhesive to secure the trusses to the supporting girders.
END PRODUCT
10. Roof Trusses to Roof Panel
The polycarbonate panel is cut accordingly to mimic the base of the bus shelter.
The cut polycarbonate is positioned to cover all surfaces and set on the pitched roof truss.
The roof is secured down using screws onto the roof trusses.
END PRODUCT
REFERENCE
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Chamberlain, M (2014) Single Digits: In Praise of Small Numbers, Princeton University Press Retrieved from: http://www.slate.com/articles/health_and_science/science/2015/07/hexagons_are_the_most_scientifically_efficient_packing_shape_as_b ee_honeycomb.html Ching, D.K., (2008) Building Construction Illustrated Fourth Edition Showalter, J. (2012) Connection Solutions for Wood-Frame Structures, American Wood Council Retrieved from: http://www.woodworks.org/wp-content/uploads/C-WSF-2012-Showalter-Connections.pdf Timberlinx. (n.d.). Retrieved October 03, 2016, from http://www.timberlinx.com/cat_a475.html Type of wood joint - Google Search. (n.d.). Retrieved October 03, 2016, from https://www.google.com/search?q=type of wood joint