Dinding Geser - 1: Teori dan Contoh Desain Dinding Geser

Summary

This video provides a comprehensive guide on the design of shear walls in special structural systems, focusing on their role in bearing earthquake loads. It covers the types of shear walls, including flexural shear walls, core walls, and shear walls with varying width-to-length ratios. The process involves calculating minimum reinforcement requirements, shear capacity, and checking for boundary elements to prevent plastic joint formation. Two methods for checking boundary element needs are discussed: displacement-based and strength-based. Additionally, the video explains how to use software and Excel sheets for detailed design and reinforcement calculations.

Takeaways

• 😀 Shear walls in special structural wall systems play a crucial role in bearing earthquake loads, acting as the main load-bearing element.
• 😀 There are three types of shear walls: flexural, shear wall with a length-to-height ratio less than 1, and core walls formed by adjacent shear walls connected by beams.
• 😀 The first step in shear wall design is to calculate the minimum reinforcement requirements, which vary based on the shear wall's load-carrying capacity.
• 😀 Reinforcement ratios for longitudinal and transverse reinforcement depend on the reinforcement diameter and shear wall load capacity.
• 😀 Axial-flexural capacity of shear walls is checked using interaction diagrams, similar to column flexural design, to ensure the wall can handle applied loads.
• 😀 Shear capacity is determined using a formula, with the maximum value set at 0.65, and variations in the shear wall size affecting the value of Alfa C.
• 😀 Special boundary elements (USS) may be required to prevent plastic joints at the base of the shear wall. These are checked using displacement-based and strength-based methods.
• 😀 Displacement-based checks involve the shear wall's deviation (Delta U) and compression zone length (C), while strength-based checks involve the stress carried by the shear wall.
• 😀 Boundary element height and length are calculated based on displacement-based and strength-based methods, which determine the required reinforcement.
• 😀 Software tools, such as Excel-based design tools, are used to calculate geometry, reinforcement needs, and the necessity for boundary elements in shear wall design.

Q & A

What are the different types of shear walls mentioned in the script?

The three types of shear walls mentioned are: 1) Flexural shear walls, which are the most common, 2) Shear walls with a ratio greater than 1, and 3) Shear walls that are connected by a beam, often referred to as core walls.

What is the importance of calculating the minimum reinforcement requirements in shear wall design?

Calculating minimum reinforcement is essential for ensuring the shear wall can properly resist earthquake loads and maintain structural integrity. It involves determining the correct ratio of longitudinal and transverse reinforcements based on the shear wall's geometry and the loads it will carry.

What are the longitudinal reinforcement ratio requirements in Indonesia for shear walls?

In Indonesia, the longitudinal reinforcement ratio for shear walls is 0.21% for diameters below 16mm and 0.5% for diameters 16mm and above.

How is the axial flexural capacity of a shear wall checked?

The axial flexural capacity of a shear wall is checked using an interaction diagram, similar to column flexural action capacity. Various software, such as vsp column CS or BCA column, can be used to compute these values.

What is the shear capacity formula for shear walls as explained in the transcript?

The shear capacity of a shear wall is given by the formula: VN = CV × (Alfa C × frame attraction) + transverse reinforcement ratio × the effect, with the maximum value of PN being 0.65.

What are special boundary elements in shear wall design?

Special boundary elements, also called intestinal boundary elements, are parts of the shear wall that require special design considerations. They are needed to resist plastic joints and ensure stability under load. The need for these elements is determined based on displacement or strength checks.

How are special boundary elements checked using the displacement-based method?

In the displacement-based method, special boundary elements are required if the length of the compression zone (C) is greater than 100 times 1.5, with Delta U (displacement) exceeding 0.005 according to SNI 2847-2019 standards.

What is the difference between the displacement-based and strength-based methods for checking special boundary elements?

The displacement-based method focuses on checking whether the displacement exceeds a specific threshold, while the strength-based method checks if the ultimate stress in the shear wall exceeds 0.2 eprime, indicating the need for special boundary elements.

How are boundary element heights calculated in shear wall design?

Boundary element heights are calculated based on the method used. In the displacement-based method, the height is the maximum of two values: mp4full and lw × Hi. In the strength-based method, the height is determined where the stress reaches 0.15 times the ultimate stress, using a linear stress distribution assumption.

What is the role of reinforcement in the body section and column section of a shear wall?

In shear wall design, the body section and column section may need additional reinforcement to prevent failure at critical points. The reinforcement in the body section ensures proper resistance to bending and shear, while the column section may require special treatment like a column restraint to handle plastic joint formations.