Cracks on Walls or Any Other Structural Members
In a bid to finding a solution to cracks on house construction walls and structural members, it is important to understand what structural cracks are all about, their causes, the types of cracks, and the challenges affecting house construction walls or structural members.
Cracks on the walls of our houses or any other structural members can be easily described as a wide or thin line running through the surface of the wall or structural member in any direction, causing separation or division of the house wall or structural member as a result of either poor site construction work, poor soil bearing capacity, or overloading of the wall or structural member.
Now that we have an idea of what cracks are all about, let's look at the types of cracks in house construction works. Basically, we have two major types of cracks, which are structural cracks and non-structural cracks.
Samples of structural cracks on house construction work.
Samples of non-structural cracks on house construction work.
For structural cracks, they occur as a result of poor structural activities like overloading of members, inadequate provision of support, improper provision of support columns in the right locations to distribute the load evenly to the ground, poor soil bearing capacity, and differential soil settlement.
For non-structural cracks, this type of crack can be associated with poor-grade materials on site, too much cement content, or lack of proper site supervision. Excessive reduction or loss of water from concrete mix as a result of increased temperature or poor formwork can equally result in cracks on our house construction walls.
Right now, we are going to dig deep into different causes of structural cracks and possible solutions to prevent them where applicable.
I will try as much as possible to use non-professional language so that homeowners or individuals new to the construction sector can benefit more from my explanation.
If you are a professional in the construction sector and want to have more professional insight about cracks on building walls, please read more on the subject from reputable construction resources.
CAUSES AND PREVENTIVE MEASURES FOR STRUCTURAL AND NON-STRUCTURAL CRACKS ON BUILDINGS
1. Foundation Movement of Soil and Differential Settlement of Soil
This is one possible situation that can cause structural failure. It can cause serious cracks in the foundation or any member of the structure.
It occurs when the soil beneath the house moves from one point to another, as in the case of an earthquake, or when there is excessive vibration of the soil due to earth-moving operations close to the house.
Another scenario is the expansion and shrinkage of soil as a result of water intake or loss of water in the soil. This can cause foundation cracks due to the expansion or shrinkage of the soil.
Preventive measures: To avoid structural failure as a result of either ground movement, expansion, or shrinkage of soil, you need to ensure that your house plan is properly designed by a civil or structural engineer.
Avoid building houses on swampy areas without the supervision of an engineer who has a proper understanding of the nature of different soil types.
2. Cracking Due to Vegetation
This is another possible situation that can cause structural cracks in a building. It occurs when you have trees close to your building and, over time, the roots of the trees expand toward the foundation of the structure and cause damage to the foundation.
Preventive measures: The best way you can prevent this type of crack from happening is to avoid planting trees too close to your house.
3. Poor Structural Design Work
Poor structural design and specifications can result in cracks in buildings during house construction. For instance, if a house plan is poorly designed by a non-professional, there is every tendency that the design will not follow the right design procedures.
This, in turn, can lead to wrong specifications and detailing, which can cause cracks as a result of shear failure or compression failure.
Preventive measures: To avoid cracks due to bad or poor structural design, it is better to engage the services of a civil engineer or structural engineer to carry out the structural design for your house construction work.
Apart from structurally induced cracks, you can also experience non-structural cracks in your house construction work as a result of poor maintenance work, lack of supervision, shrinkage, thermal movement, elastic deformation, creep movement, chemical reactions, poor workmanship, incorrect cement quantity, corrosion, and poor construction practices.
These cracks can be seen on any structural member such as beams, columns, slabs, or walls. For non-structural cracks, I will discuss some of the causes of cracks and how you can prevent them where possible.
4. Shrinkage Cracks
This is a type of crack that occurs as a result of excessive loss of water in concrete. During a casting operation, if the rate of evaporation is higher than that of the bleeding water at the surface of the concrete, this will eventually lead to the loss of excess water, which can result in shrinkage cracks on the structural member. This is mostly common on slab members.
Preventive measures: One way we can prevent shrinkage cracks is to provide good formwork materials and ensure that the cement content in the concrete is not excessive.
5. Cracks Due to Creep Movement
This type of crack on our house walls or concrete members is usually caused by long-term loading on walls or structural members. It is a gradual process, and the cracks may become noticeable over a long period.
Cracks due to creep become more noticeable as a result of excessive load on the structural member, which can lead to deformation of the house wall over time.
Also, when the water-cement ratio of your concrete mix is too high, it can contribute to long-term deformation and cracking. Apart from that, temperature changes in steel members can equally contribute to movement and deformation in structural members.
Preventive measures: Since you now understand some of the causes of cracks due to creep effects, it becomes easier to provide possible solutions to avoid excessive creep movement in our house construction projects.
Firstly, to avoid excessive deformation and related cracking, it is important to use the appropriate concrete mix ratio, avoid excessive addition of water, and ensure that the right aggregate is used for the construction work. Also, compression reinforcement should be provided in structural members where required by the structural design.
Secondly, it is important to allow concrete to cure properly before removing formwork from structural members. Apart from that, we should always provide appropriate cross-sections for our structural members based on proper structural design.
6. Cracks Due to Corrosion
Corrosion is a reaction process that mainly occurs with steel when it comes into contact with water, oxygen, and other substances that can promote corrosion.
This reaction produces corrosion products on the surface of the structural reinforcement, which can increase the volume around the steel reinforcement.
This increase in volume can create internal pressure within the surrounding concrete and eventually lead to cracks in the structural member.
Preventive measures: From understanding corrosion-related cracking, it becomes easier to provide solutions to reduce the risk of cracks on our house projects caused by corrosion.
One way we can avoid it is to ensure that our concrete mix is properly designed and adequately compacted. We should use an appropriate concrete mix that provides sufficient durability and resistance to water penetration.
Also, we should provide adequate concrete cover and ensure that the reinforcement is properly spaced and detailed according to the structural design in order to provide a good structural bond between the concrete and reinforcement.
7. Poor Construction Practice
Normally, there are different approaches to construction practice, but some construction practices have been abused over the years as a result of carelessness, greed, ignorance, and negligence.
The major causes include engaging unqualified personnel for construction works and the provision of poor or low-quality materials by clients for construction projects.
Preventive measures: One simple way to prevent cracks in structural members as a result of poor construction work is to engage qualified professional engineers to monitor the construction process properly and ensure that quality materials are used for the construction project.
Conclusion
There are other structural and non-structural factors that can result in cracks in house construction work, but they are not covered here since the idea of this article is to explain some common activities and conditions that can easily result in cracks in structural members.
I hope and believe you will make good use of the solutions provided here on how to prevent structural and non-structural cracks in construction activities. Feel free to let me know if there are areas where you need more clarification.
