Adding polymers and steel fibers to concrete mix can slightly increase the tensile strength of concrete to a certain level, though it can not reach that much anticipated value close to >50% of compressive strength.
Would it be possible to try and achieve that through some sort of chemical reaction?
There have been attempts to improve the tensile strength of concrete through manipulating the chemical make-up, for example through the use of very reactive powder composites (read about reactive powder concrete). However, even when relatively high tensile strengths can be achieved, it is still a small percentage compared to the resulting compressive strength. The challenge at the moment is that, any nano-scale improvements in tensile strength equally lead to an increase in compressive strength as well. It is a positive correlation always, but it's an interesting area of research to explore.
There have been attempts to improve the tensile strength of concrete through manipulating the chemical make-up, for example through the use of very reactive powder composites (read about reactive powder concrete). However, even when relatively high tensile strengths can be achieved, it is still a small percentage compared to the resulting compressive strength. The challenge at the moment is that, any nano-scale improvements in tensile strength equally lead to an increase in compressive strength as well. It is a positive correlation always, but it's an interesting area of research to explore.
I agree with Muzafalu. But you never know with the latest developments we are seeing in composite materials and the the use of new chemical components. On the other hand, some may argue that we already have a material that has excellent tensile qualities (steel), and it is this complementarity between concrete and steel that has made the composite material dominating the construction industry for decades. Having said that, I also agree with Muzafalu that this is an exciting new area of research.
Nano particles such as nano-SiO2, nano-Fe2O3 and carbon nanofibrs and carbon naotubes can improve the mechanical properties of cementitious materials. I have done some Experimental Work in this field recently and gained good results.
In general any approach to modify nano-scale properties of cement-based materials that improves their compressive strength, would also enhance their tensile strength. But, if you are particularly looking for direct impact on tensile strength, you can incorporate functionalized carbon nanotubes or silanized polymers during the formation of hydration products.
Latex polymers are popular solution. Latest technology has made special polymers which acts as dispersing agents as well as bonding enhancement agents.
My colleague utilised specialised equipment to gauge the mechanical properties of nano-reinforced cement with CNT to a certain degree of success. His target is to the ITZ.
His paper has been published recently
- Badges
- Science topic