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12.1. EXPERIMENT NO: 12
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Today we'll explore the importance of staircase design in buildings. Why do you think staircases are crucial in architecture?
Because they allow people to move between floors?
Exactly! But they also need to be designed for safety, aesthetic appeal, and functionality. Does anyone know what types of staircases we will be discussing today?
Dog-legged and open well staircases?
Correct! Remember the acronym DOG for Dog-legged Staircase: Design, Orientation, and Gradient. Let’s delve deeper into each design.
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Now let's look at the specifics of the dog-legged staircase. What is the total height we need to consider?
It’s 3.3 meters!
Great! And how thick is the floor slab, and what are the dimensions for the steps?
The floor slab thickness is 150mm, the tread is 300mm, and the rise is 150mm.
Perfect! Remember the rhyme '150 for flat, 300 to step flat'. Let’s understand how these dimensions affect the drawing.
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Next, we will explore the open well staircase design. What’s the advantage of an open well staircase compared to a dog-legged design?
It uses space more efficiently and is visually appealing?
That's correct! Not forgetting it allows more light and air. What are the dimensions we’ll work with for the open newel staircase?
4.5m by 5.4m, with a height of 3.6m?
Exactly! And let's remember the acronym OPEN: Orientation, Parameters, Efficiency, and Newel. Now, let’s practice some drawing layouts.
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Can anyone tell me why using a reinforced material like RCC is crucial in these designs?
Because it helps support the structure and distribute weight?
Exactly! In our exercises, we have specific reinforcement details—like 10ϕ@125c/c for the dog legged staircase. What do you think that means?
It means we need to place 10mm bars every 125mm apart?
Well done! This is where understanding materials and reinforcement details is essential. Remember to keep this reinforcement in mind as you draft your designs.
Overview
Short Summary
This section focuses on the drawing and designing of various types of staircases, specifically the dog-legged and open well staircases, emphasizing dimensions, materials, and technical specifications.
Medium Summary
The section details practical exercises for creating drawings of dog-legged and open well staircases for office buildings. It covers crucial parameters like measurements, materials, and reinforcement details essential for structural integrity and functionality.
Detailed Summary
Experiment No: 12
In this section of the chapter dedicated to computer-aided building planning and drawing, students are tasked with designing two significant types of staircases for an office building: the dog-legged staircase and the open well staircase.
The dog-legged staircase is characterized by a series of steps that return on themselves, creating two flights separated by a landing. In contrast, the open well staircase features a rectangular opening, allowing for a more spacious appearance.
Key parameters include:
- Dimensions: Total heights, individual stair measurements (tread and riser), and overall staircase width all affect the usability and aesthetics.
- Material specifications: Reinforced cement concrete (RCC) is typically used, with detailed reinforcement bars specified for structural loading.
- Exercise
12.1focuses on drawing an RCC dog-legged staircase, outlining specific dimensions like a vertical distance of 3.3m between floors, floor slab thickness, along with tread and rise dimensions. - Exercise
12.2elaborates on the design details for an open newel staircase, indicating similar parameters while also highlighting a different internal dimension.
These exercises serve as practical applications in understanding structural drawings, adherence to engineering standards, and the impact of design choices on building functionality.
Audio Book
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Create a free accountDraw plan and sectional elevation of an open newel staircase with a rectangular well for an office building with the following data: Inside dimensions of staircase = 4.5m x 5.4m. Height between the floors is 3.6m. Thickness of the floor slab and landing slab is 150mm. Width of landing=1.5m. Width of stair = 1.5m. Tread=300mm,riser=150mm. Waist slab thickness = 150mm. Reinforcement details: Main steel:12ϕ@150 c/c spacing and Distribution: 8ϕ @ 250 c/c spacing.
Detailed Explanation
For this exercise, you need to draft a plan and sectional elevation of an open newel staircase that features a rectangular well. The staircase occupies inside dimensions of 4.5 meters in width and 5.4 meters in length. The overall height from one floor to the next is 3.6 meters. Just like the previous staircase, the floor slab and landing slab are both 150 millimeters thick, providing strong support.
The width of the landing, where people can stand safely, is also 1.5 meters, which matches the width of the stair itself. Each step is again designed with a tread of 300 millimeters and a riser of 150 millimeters, leading to a comfortable design for users. The thickness of the waist slab is consistently maintained at 150 millimeters.
Reinforcement for this staircase includes main steel which is 12 mm in diameter, laid out at 150 mm center-to-center spacing, while distribution steel is made up of 8 mm bars at 250 mm center-to-center spacing.
Examples & Analogies
Think of stairs in a public building, like a library or an office. They need to be broader and safer because more people use them than at home. The open newel staircase design, much like a spiral staircase, allows for an elegant, open look, much like how you’d want an open atrium in a building. The structure needs to balance functionality with aesthetics, ensuring safety while being visually appealing. This is similar to planning a beautifully landscaped garden that is also functional, providing paths for visitors to walk through safely.
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Key concepts
Core takeaways and short definitions to help you quickly recall the key ideas from this section.
- Staircase Design:
Importance of staircases in the overall architecture and flow of buildings.
- Structural Integrity:
Role of material selection and reinforcement in ensuring the safety and durability of staircases.
- Measurements:
The significance of accurate measurements and dimensions in stair design.
Examples
Step-by-step examples to apply the section's ideas and test your understanding.
The design of a dog-legged staircase in a multi-story building, accommodating enhanced space usage and aesthetic appeal.
An open well staircase in an office, providing a spacious and inviting environment while ensuring safety and compliance with building codes.
Memory aids
Imagine a tall building where the stairs twist and turn like a dance. The dog-legged staircase allows you to move smoothly while the open well staircase brings light into every step.
Flash Cards
Glossary
Dog-legged staircase
A staircase characterized by two flights of stairs that return on themselves, connected by a landing.
Open well staircase
A type of staircase that features an opening in the shape of a rectangle, allowing more space and light.
RCC (Reinforced Cement Concrete)
Concrete that is strengthened with steel reinforcement bars to improve its structural performance.
Tread
The horizontal part of the stair that individuals step on when climbing or descending.
Riser
The vertical portion of the stair between each tread, providing the stepping height required.
Landings
A flat area at the top or bottom of a staircase or where a flight changes direction.