Understanding Soft Story Buildings and Their Vulnerability to Earthquakes

Oct 13, 2025 by thesweetdesigns.com 30 views

Understanding Soft Story Buildings and Their Vulnerability to Earthquakes

Soft story buildings, also known as soft levels, are a type of structure that has low strength and resistance to the pressure produced by earthquakes. These buildings are characterized by the existence of many openings and a little wall, making them vulnerable to shocks. In this study, we will analyze the impact of the use of walls on the ground floor on the stiffness and stability of the building when exposed to the earthquake.

Soft story buildings are a common phenomenon in many parts of the world, particularly in areas prone to earthquakes. The characteristic of these buildings is the existence of a soft floor, which is a floor with a low strength and resistance to the pressure produced by the earthquake. The soft floor is often located on the ground floor, and it is typically made of a material that is not strong enough to withstand the forces generated by the earthquake.

Methodology and Analysis

In this study, we used a three-span configuration as the research object. The length of the edge reaches 8 meters, and the middle span is 6 meters. The height of the ground floor considered as a soft floor is 6 meters, while the level above has a height of 4 meters. The method used in this study was the Equivalent compressive diagonal method put forward by Saneinejad and Hobbs in 1995.

The analysis process was carried out in stages. The first stage is to analyze buildings without walls on the ground floor, and the second stage is to integrate walls on the ground floor. The analysis shows that buildings that do not use walls on the ground floor only have a stiffness of 10,461.69 kg/cm with a displacement (shift) of 0.283959 m and base shear (basic shear force) of 84,245.67 kg. This condition indicates that the building is almost collapsed when exposed to the earthquake.

The Impact of Walls on the Ground Floor

Conversely, after the wall is added to the ground floor, the building shows a significant increase in terms of stiffness, reaching 194,190.36 kg/cm, with a displacement that increases to 0.977017 m and is able to withstand loads of 4,629,017.49 kg. The ratio between the two analyzes shows an extraordinary increase: stiffness increased by 94.61%, displacement decreased by 70.94%, and base shear increased by 98.18%.

This analysis underlines the importance of building structure designs that pay attention to elements that can increase earthquake resistance. The use of walls on the ground floor is very effective in increasing the stiffness and stability of the building, which can reduce the risk of collapse. Therefore, for engineers and architects, understanding the characteristics of soft stories and the impact of the use of structural elements is very important in the design of safe and earthquake-resistant buildings.

Implications for Building Regulations and Safety

This study is also important in the context of building regulations in Indonesia, where earthquakes are a natural phenomenon that often occurs. Further research and application of appropriate design become a strategic step to improve the safety of buildings and its inhabitants. By understanding and applying these principles, we can minimize the negative impacts of the earthquake on the structure of the building and ensure the survival of the community.

Conclusion

In conclusion, this study highlights the importance of building structure designs that pay attention to elements that can increase earthquake resistance. The use of walls on the ground floor is a simple and effective way to increase the stiffness and stability of the building, which can reduce the risk of collapse. Therefore, for engineers and architects, understanding the characteristics of soft stories and the impact of the use of structural elements is very important in the design of safe and earthquake-resistant buildings.

Recommendations for Future Research

Based on the findings of this study, we recommend further research on the following topics:

The impact of different types of walls on the ground floor on the stiffness and stability of the building
The effect of different materials used for the walls on the ground floor on the stiffness and stability of the building
The impact of different building configurations on the stiffness and stability of the building

By conducting further research on these topics, we can gain a better understanding of the factors that affect the stiffness and stability of soft story buildings and develop more effective design strategies to improve the safety of buildings and its inhabitants.

Limitations of the Study

This study has several limitations that should be noted. Firstly, the study only analyzed a specific type of building configuration, and the results may not be generalizable to other types of buildings. Secondly, the study only considered the impact of walls on the ground floor on the stiffness and stability of the building, and did not consider other factors that may affect the building's performance during an earthquake.

Future Directions

Despite the limitations of this study, the findings highlight the importance of building structure designs that pay attention to elements that can increase earthquake resistance. Future research should focus on developing more effective design strategies to improve the safety of buildings and its inhabitants. Additionally, further research should be conducted to investigate the impact of different types of walls on the ground floor on the stiffness and stability of the building, as well as the effect of different materials used for the walls on the ground floor on the stiffness and stability of the building.

Conclusion

Q: What is a soft story building?

A: A soft story building is a type of structure that has low strength and resistance to the pressure produced by earthquakes. These buildings are characterized by the existence of many openings and a little wall, making them vulnerable to shocks.

Q: Why are soft story buildings prone to collapse during earthquakes?

A: Soft story buildings are prone to collapse during earthquakes because they have a soft floor, which is a floor with a low strength and resistance to the pressure produced by the earthquake. The soft floor is often located on the ground floor, and it is typically made of a material that is not strong enough to withstand the forces generated by the earthquake.

Q: What is the Equivalent compressive diagonal method?

A: The Equivalent compressive diagonal method is a method used to analyze the behavior of buildings during earthquakes. It was put forward by Saneinejad and Hobbs in 1995 and is used to determine the stiffness and stability of buildings.

Q: How does the use of walls on the ground floor affect the stiffness and stability of a building?

A: The use of walls on the ground floor can significantly increase the stiffness and stability of a building. By adding walls to the ground floor, the building's ability to resist the forces generated by an earthquake is increased, reducing the risk of collapse.

Q: What are the benefits of using walls on the ground floor in soft story buildings?

A: The benefits of using walls on the ground floor in soft story buildings include increased stiffness and stability, reduced risk of collapse, and improved safety for occupants.

Q: Can soft story buildings be retrofitted to make them more earthquake-resistant?

A: Yes, soft story buildings can be retrofitted to make them more earthquake-resistant. This can be done by adding walls to the ground floor, using stronger materials, and implementing other design strategies to improve the building's ability to resist the forces generated by an earthquake.

Q: What are some common mistakes made when designing soft story buildings?

A: Some common mistakes made when designing soft story buildings include:

Not considering the soft floor's impact on the building's stiffness and stability
Not using walls on the ground floor to increase the building's ability to resist the forces generated by an earthquake
Not using stronger materials for the building's structure
Not implementing other design strategies to improve the building's ability to resist the forces generated by an earthquake

Q: How can engineers and architects ensure that soft story buildings are designed to be earthquake-resistant?

A: Engineers and architects can ensure that soft story buildings are designed to be earthquake-resistant by:

Conducting thorough analyses of the building's behavior during earthquakes
Using walls on the ground floor to increase the building's ability to resist the forces generated by an earthquake
Using stronger materials for the building's structure
Implementing other design strategies to improve the building's ability to resist the forces generated by an earthquake
Consulting with experts in earthquake engineering and architecture

Q: What are some future directions for research on soft story buildings and earthquake resistance?

A: Some future directions for research on soft story buildings and earthquake resistance include:

Investigating the impact of different types of walls on the ground floor on the stiffness and stability of the building
Studying the effect of different materials used for the walls on the ground floor on the stiffness and stability of the building
Developing more effective design strategies to improve the safety of buildings and its inhabitants during earthquakes

Q: How can the public stay safe during earthquakes?

A: The public can stay safe during earthquakes by:

Being aware of the building's design and construction
Knowing the evacuation procedures and emergency exits
Staying informed about earthquake risks and preparedness
Following evacuation instructions from authorities
Staying away from buildings that are prone to collapse during earthquakes

Q: What are some resources available for further information on soft story buildings and earthquake resistance?

A: Some resources available for further information on soft story buildings and earthquake resistance include:

The American Society of Civil Engineers (ASCE)
The American Institute of Architects (AIA)
The National Earthquake Hazards Reduction Program (NEHRP)
The Federal Emergency Management Agency (FEMA)
The International Building Code (IBC)