Calculate Wall Bracing - Part 6 - Design Bracing Systems - Walls

Summary

In this sixth installment of the 'calculating wall bracing' series, the host explores various bracing systems and their resistance capacities. They discuss the requirements for Wind Direction 1 and 2, referencing the Timber Framing Code Table 8.18 for types of bracing like diagonal timber, metal braces, and plywood sheets. The video provides calculations for resistance based on bracing length and material, highlighting methods for installation like Method A and B for plywood. The goal is to determine the number of bracing units needed to withstand forces in different wind directions, with a promise to delve deeper in the next video.

Takeaways

• 🏗️ The video is part of a series on calculating wall bracing, focusing on the different systems available and their resistance capacities.
• 📊 For Wind Direction 1, the required resistance is 26.758 kN, and for Wind Direction 2, it's 10.127 kN.
• 📚 The Timber Framing Code Table 8.18 provides guidelines on the types of bracing and their resistance capabilities.
• 🔍 Diagonally opposed timber and metal brace angles offer a bracing capacity of 0.8 kilonewtons per meter, with a maximum length of 2.7 meters.
• 📐 A tensioned metal strap or brace without stud ties has a resistance of 1.5 kN, and with a length of 2.7 meters, it provides 4.05 kN of resistance.
• 🔩 Metal angle braces with stud ties increase the resistance to 3 kN per meter, resulting in 8.01 kN for a 2.7-meter length.
• 📝 Plywood sheathing offers varying resistance depending on the method of installation and the thickness of the ply, with standard nailing providing 4.8 kN per sheet.
• 🔨 Method A of plywood installation, which involves specific floor fixing and nail quantities, can provide up to 7.68 kN of resistance per sheet.
• 🛠 The resistance of plywood also depends on its thickness, with 4.5mm ply offering 7.5 kN per meter and 7mm ply providing 8.7 kN per meter.
• 📉 Despite the high resistance potential of certain bracing systems, economic and practical considerations may lead to choosing other options.
• 🔄 The next video will address the calculation of the number of bracing units required to resist forces in each wind direction.

Q & A

What is the purpose of the video series 'Buildsum'?

The video series 'Buildsum' is focused on educating viewers on calculating wall bracing, with this particular video being the sixth part of the series.

What are the required resistance values for Wind Direction 1 and Wind Direction 2 as mentioned in the script?

For Wind Direction 1, the required resistance is 26.758 kN, and for Wind Direction 2, it is 10.127 kN.

What is the source of information for the types of bracing and their resistance capacities mentioned in the video?

The information comes from the Timber Framing Code Table 8.18, which outlines different types of bracing and the resistance they provide.

What is the bracing capacity provided by diagonally opposed timber or metal brace angles?

Diagonally opposed timber or metal brace angles provide a bracing capacity of 0.8 kilonewtons per meter.

How much resistance does a tensioned metal strap or a tension brace without any stud ties offer?

A tensioned metal strap or a tension brace without any stud ties offers 1.5 kN of resistance.

What is the resistance capacity of a metal angle brace with stud ties?

A metal angle brace with stud ties has a resistance capacity of 3 kN per meter.

What is the resistance provided by a plywood sheet with standard nailing?

A plywood sheet with standard nailing provides 3.4 kN of resistance per meter.

How does the thickness of the plywood affect its resistance capacity?

The resistance capacity increases with the thickness of the plywood; for example, a 4.5mm thick plywood provides 7.5 kN per meter, while a 7mm thick plywood provides 8.7 kN per meter.

What are the two methods mentioned for fixing plywood to the floor, and what is the difference between them?

The two methods mentioned are Method A and Method B. They differ in the way the plywood is fixed to the floor and the number of nails used, with Method A requiring more work and providing a higher resistance of 6.4 kN per meter.

What is the total resistance provided by a 1.2m x 8.7mm thick plywood sheet?

A 1.2m x 8.7mm thick plywood sheet provides a total resistance of 10.44 kN.

What will be the focus of the next video in the series?

The next video will focus on calculating the number of bracing units needed to resist the forces in each wind direction.

Outlines

00:00

🏗️ Wall Bracing Systems Overview

This paragraph introduces the video's focus on calculating wall bracing, specifically discussing the various bracing systems available and their resistance capacities. The speaker recaps the need for 26.758 kN of resistance from Wind Direction 1 and 10.127 kN from Wind Direction 2, referencing the Timber Framing Code Table 8.18 for bracing types and their resistance values. The paragraph sets the stage for an exploration of different bracing methods, including diagonal timber, metal brace angles, tensioned metal straps, and plywood sheets, each with specific resistance capacities and installation considerations.

Keywords

💡Wall Bracing

Wall bracing refers to the structural elements used to support and strengthen walls, particularly against lateral forces such as wind. In the video, the theme revolves around calculating the necessary wall bracing to resist specific forces from different wind directions, emphasizing its importance in construction for safety and stability.

💡Kilonewtons (kN)

Kilonewtons is a unit of force in the metric system, where 1 kN is equivalent to 1000 newtons. In the script, the video discusses the required resistance in kilonewtons for wall bracing to withstand wind forces, such as needing 26.758 kN for Wind Direction 1 and 10.127 kN for Wind Direction 2.

💡Timber Framing Code

The Timber Framing Code is a set of regulations and guidelines that dictate the standards for timber construction. The script references Table 8.18 from this code, which provides different types of bracing and their respective resistance capacities, indicating its role in guiding construction practices for safety and compliance.

💡Diagonally Opposed Timber

Diagonally opposed timber refers to a bracing method where timber pieces are placed diagonally across a structure, often in opposing directions, to provide stability and resistance to forces. The script mentions this type of bracing and its capacity to resist forces, calculated as 0.8 kN per meter of its length.

💡Metal Braces

Metal braces are structural components made of metal that are used to reinforce and provide rigidity to a construction. The video script discusses various types of metal braces, such as angle braces and tensioned metal straps, and their specific resistance capacities in bracing systems.

💡Bracing Capacity

Bracing capacity is the measure of the force that a bracing system can withstand. The script provides calculations for the bracing capacity of different systems, such as diagonally opposed timber and metal braces, which is crucial for determining the appropriate number and type of braces needed.

💡Plywood

Plywood is a type of engineered wood made from thin layers of wood veneer, and it is used in construction for various purposes, including wall bracing. The script explains the resistance provided by plywood sheets, depending on their standard nailing and fixing methods, illustrating its role in enhancing wall stability.

💡Tensioned Brace

A tensioned brace is a type of bracing that is tightened to provide additional structural support. The script mentions tensioned metal straps and braces with stud straps, which have a higher bracing capacity compared to untensioned ones, highlighting the importance of tension in maximizing resistance.

💡Resistance Calculation

Resistance calculation is the process of determining the amount of force a bracing system can resist. The video script provides examples of how to calculate the resistance for different bracing types, such as multiplying the length of a brace by its resistance per meter to find the total resistance it can provide.

💡Installation Methods

Installation methods refer to the techniques used to fix or secure structural elements in place. The script discusses Method A and Method B for plywood installation, which differ in the way they are fixed to the floor and the number of nails used, affecting the overall resistance and effort required for installation.

💡Economical Considerations

Economical considerations involve evaluating the cost-effectiveness of construction methods or materials. The script briefly touches on the potential for using a single plywood sheet to meet the resistance requirement for Wind Direction 2, but also notes other factors that might make this option uneconomical, such as the need for additional sheets.

Highlights

Introduction to part six of a series on calculating wall bracing.

Explanation of the required resistance from Wind Direction 1 and 2: 26.758 kN and 10.127 kN respectively.

Overview of different bracing systems available and their resistance capacities.

Details on diagonally opposed timber and metal brace angles, with a resistance of 0.8 kN/m.

Calculation example for maximum length bracing resistance: 2.7 m x 0.8 kN/m = 2.16 kN.

Description of tensioned metal strap or tension brace without stud ties, offering 1.5 kN of resistance.

Metal angle brace with stud ties resistance capacity and calculation for a 2.7 m length.

Introduction to plywood as a bracing material with a resistance of 3.4 kN/m.

Calculation for average plywood sheet resistance: 1.2 m x 3.4 kN/m = 4.08 kN.

Different methods of fixing plywood, with Method A and Method B providing varying resistance levels.

Method A installation details and its higher resistance capacity of 7.68 kN for a 1.2 m sheet.

Consideration of the practicality of using plywood for Wind Direction 2 resistance.

Discussion on the thickness of plywood and its impact on resistance: 4.5mm and 7mm thicknesses.

Calculation for resistance of thicker plywood: 1.2 m x 8.7 kN/m = 10.44 kN.

Consideration of the economic and practical aspects of using different bracing systems.

Teaser for the next video, which will calculate the number of bracing systems needed for each wind direction.

Invitation to subscribe to the YouTube channel and follow on Facebook for more content.

Transcripts

GDay and welcome back to Buildsum and this is part six in a series of

calculating wall bracing and in this video I'm just going to look at the

systems of bracing that are available to us and how much they can actually resist

so just to recap basically what we've done we've been through and we've worked

out that from Wind Direction 1 we need 26.758 kN

of resistance and Wind Direction 2 we need 10.127 kN

of resistance okay so the Timber Framing Code Table 8.18

sets out the different types of bracing we can use and the

amount of resistance they will provide okay so here we've got two diagonally

opposed timber all metal brace angle braces okay says they have to read

between 1.8 to 2.7 so we get the right angle you know

less than, more than thirty in less than sixty basically degrees so they provide

us with a resistance or a bracing capacity of 0.8 kilonewtons per metre so

if we went with a maximum length here 2.7, 2.7 x 0.8

gives us 2.16 kN of resistance for that

type of bracing and they do that for all the bracing so here's a tensioned metal

strap or a tension brace without any stud ties it gives us 1.5 kN

of resistance so if it was 2.7m long it would

give us 4.05 kN of resistance for that unit for a metal

angle brace with stud ties again 1.5 so again 4.05 or resistance if you went to a tensioned brace with stud straps okay

doubles the capacity so it gives you a bracing capacity of 3m

so if you went 2.7 long you get 8.01 kN of resistance out

of that bracing setup, we also have your plywood so apply sheet gives you

3.4 kN of resistance per metre so your average sheet is

1.2 so 1.2 x 3.4 gives

you 4.8 kN of resistance per plywood sheet all right that's just

standard nailing and then depending on how you fix it okay you can use

different methods different Method A and Method B just talks about how it's

actually fixed to the floor and the amount of nails that you put around the

sheet ok you can look them up in the code itself so Method A, 6.4 kN

per metre by 1.2 that will give you a resistance of 7.68 kN

it sounds really good but there's a lot of work to actually get a

method a installation so you have to toss up whether you're going to go to

that extra work or you're just going to put in the extra sheets okay and here's

another one so again another plywood system depending on the thickness of the

ply this time so if the ply was 4.5mm thick you'll give

you a resistance of 7.5 and if it was 7mm thick that will give

you a resistance of 8.7 per metre so again 1.2 x 8.7

you could possibly get a resistance of 10.44 kN

out of that sheet okay now that sounds really good this means that

we could probably get out Wind Direction 2 with 1 sheet however there are a

few other factors that may make that uneconomical and just not worth the effort

because we're gonna have to put extra sheets on anyway which you'll see later

on, Okay so there are different types of bracing systems just a few of them there

are more in the timber framing code okay but that just gives you an idea or

of the bracing capacity of some of those systems and then in the next video we're

going to work out how many we actually need to resist the force in each route

directions G'day I'm back just let you know that if

you like this video you can subscribe to my youtube channel or you can follow me

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