Self-Healing Concrete

Engineers are now looking to God’s creation for innovative ideas in architecture.
From new ventilation systems that imitate termite mounds to plots of plants
on rooftops, building design will never be the same. Even the basic building
block, concrete, has been altered based on insights from human muscles.

Three basic types of muscles exist in the human body—smooth, skeletal, and
cardiac (heart). Two are of special interest to concrete engineers. Smooth muscles control most involuntary actions, such as digestion. Their fibers are arranged
randomly and don’t bulk up. Skeletal muscles allow us to move voluntarily, and
these can be strengthened with exercise.

Unlike smooth muscles, skeletal muscles are organized in intricately bound
bundles. A skeletal muscle is a bundle of fascicles, and each fascicle is a
bundle of fibers. Each fiber contains hundreds of myofibrils, and every myofibril
is a bundle of about 4,500 protein filaments. Each of those filaments is a bundle
of many long protein polymers.

Because skeletal muscle is a bundle of bundles of bundles, heavy burdens get
divided among the many bundles. Sharing the load this way protects against overstressing
the muscle. Instead of tearing the entire muscle, excessive loads normally cause
only small scattered tears. These tiny tears are called microtrauma. When microtrauma
occurs, muscles spend a few days building more protein to replace the torn or
damaged protein polymers. Soon the muscle fibers are as strong as ever. Repairing
a large tear would be very difficult, but minor injuries are generally small
and easily mended.

Photo: Steve Gschmeissner | Photo Researchers, Inc.

This is all well and good, but how does muscle structure specifically apply
to concrete?

Ordinary concrete is a mixture of cement, sand, and water. Once it dries, concrete
is brittle, so when it gets stressed, it cracks. Cracks typically spread through
the concrete and require expensive repairs. By replacing the sand with microfibers,
the concrete isn’t brittle—in fact, it can even bend! When the stress on the
concrete is excessive, the cement around the microfibers is designed to fracture
before the microfibers.

Microfibers divide the concrete into small sections, akin to muscle bundles.
This allows heavy loads to be divided and shared. Because the microfibers are
arranged randomly, like those in smooth muscle, stress from any direction can
be absorbed. And when a small crack does appear, it does not spread beyond its
section.

And like muscle, this new concrete repairs itself. Tears in stressed muscles
are usually small, allowing intact fibers to act like splints during healing.
Likewise, microfibers in selfhealing concrete bridge tiny cracks while the concrete
heals itself. The dry cement powder in a small crack mixes with water vapor
and carbon dioxide from the air to form limestone. This limestone fills the
tiny crack and dries around the microfibers.

The “healed” concrete is as tough and strong as the original. But like smooth
muscle, this remodeled concrete does not bulk up. If it did, bridges and buildings
made from it would swell!

Self-healing concrete is an amazing invention, based on God’s designs. The
possibilities are unlimited for those who expect to find intelligent design
throughout the created world!

SourceThis article originally appeared on answersingenesis.org

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