Manual Methods Using Spreadsheets (MS Excel) in BBS

Bar Bending Schedule (BBS) is a crucial document used in construction projects to outline the quantity, size, and length of reinforcement steel required. While modern software tools are widely used for BBS preparation, many engineers still rely on manual methods, particularly spreadsheets like Microsoft Excel (MS Excel). Using Excel for BBS provides flexibility, cost-effectiveness, and easy customization for specific project needs. This article explores the manual methods for preparing a BBS using MS Excel, along with examples.

Advantages of Using MS Excel for BBS

• Flexibility: Excel allows engineers to create custom layouts, formulas, and calculations to meet specific project requirements.
• Cost-Effective: Excel is often available in most organizations and does not require additional software costs.
• Easy to Update: It is easy to make changes or updates in Excel, especially when modifications in design or quantities occur.
• Data Analysis: Excel provides powerful data analysis tools, such as sorting, filtering, and pivot tables, which can be useful for organizing BBS data.

Steps for Preparing BBS Using MS Excel

Creating a BBS using Excel involves several key steps. Let’s break down the process with examples:

Step 1: Create a Template

First, you need to set up the Excel worksheet with appropriate columns to capture the necessary data. Typically, the following columns are included in a BBS template:

• Sl. No.: Serial number for each bar in the schedule.
• Type of Bar: Indicates the type of reinforcement bar (e.g., main bars, stirrups, links).
• Diameter (mm): The diameter of the bar in millimeters.
• Length (m): The length of the reinforcement bar in meters.
• Quantity: The number of bars required for the element.
• Total Length (m): The total length of steel used for that specific bar type.
• Weight (kg): The weight of each bar, which can be calculated using the formula: Weight (kg) = (d² × L) / 162

Step 2: Input Data

Once the template is set up, you can begin entering the necessary data for each bar type. For example, consider a beam that requires the following steel reinforcement:

In this example, we have entered data for two types of bars: main bars and stirrups.

Step 3: Calculate Total Weight of Steel

To calculate the total weight of steel for each bar, use the formula:

Weight (kg) = (d² × L) / 162

For the main bar with a diameter of 16 mm and a length of 5 meters:

Weight (kg) = (16² × 5) / 162 = (256 × 5) / 162 = 1280 / 162 = 7.93 kg

For the stirrup with a diameter of 8 mm and a length of 1.5 meters:

Weight (kg) = (8² × 1.5) / 162 = (64 × 1.5) / 162 = 96 / 162 = 0.59 kg

By applying this formula to all the bars in the schedule, the total steel usage can be easily calculated.

Step 4: Calculate Total Steel Quantity

To calculate the total steel quantity, simply multiply the weight of each bar by the quantity (number of bars). For the main bars:

Total Weight = 7.93 kg × 4 = 31.72 kg

For the stirrups:

Total Weight = 0.45 kg × 12 = 5.40 kg

Now, the total steel weight for the beam will be:

Total Steel Weight = 31.72 kg + 5.40 kg = 37.12 kg

Step 5: Finalizing the BBS

After entering the data and performing the necessary calculations, you can finalize the BBS in Excel. This will include organizing the data, ensuring all calculations are correct, and preparing a final summary sheet that includes the total steel weight for the entire project. You can also use Excel’s built-in features such as pivot tables or charts to further analyze and present the data.

Example of a Complete BBS Using Excel

Below is a complete example of a simple BBS for a beam with different types of reinforcement:

Conclusion

Manual methods using spreadsheets (MS Excel) in BBS are widely employed in the construction industry due to their flexibility, ease of use, and cost-effectiveness. By following the steps outlined in this article, engineers can prepare accurate and detailed BBS for their projects. Excel allows for easy customization, calculation of steel quantities, and tracking of materials, making it a reliable tool for managing reinforcement steel in construction projects.