Expansive concrete is a specialized type of concrete that expands when mixed with water leading to a larger volume after setting. Such concrete is usually used to compensate for shrinkage. However. although expansive concrete can also be used in self-stressing concrete (chemical prestressing). https://www.roneverhart.com/84-inch-Outswing-Double-Door-Security-Door-Bars-ESI-SB-01-0084/