TABLE OF CONTENTS It was once said that concrete is an ancient but not an eternal material. Concrete strength tends to increase with age, but only up to a point. Eventually, concrete deteriorates and requires maintenance and repair, just like any other construction material. Modern science has made enormous progress in understanding the reasons for the deterioration of concrete, and today's concrete structures if properly designed and built should prove quite durable. Unfortunately, most of the building stock in this country and worldwide is of an earlier vintage, much of it constructed at the turn of the twentieth century, when concrete theory was still in its infancy. Now, many decades later, these aging buildings need rehabilitation.
In this chapter, we discuss strategies for repairing concrete, focusing on restoration of its structural capacity, appearance, and durability. The topic of strengthening concrete buildings is addressed in Chap. 4, upgrading slabs on grade in Chap. 6, and renovation of post-tensioned structures in Chap. 7.
The general approach to the evaluation of distressed concrete buildings and assessment of their structural capacities is described in Chap. 2. This necessary process includes information gathering, document review, site investigation, and office analysis. For the purpose of our discussion here, we assume that all these steps have already been taken and that the causes of the problems are known, so that we can concentrate on the solutions.
The discussion in this chapter assumes that the repair option has already been chosen, except in some...
