Cracking is a common problem in concrete structures in real-life service conditions. In fact, crack-free concrete structures are very rare to find in real world. Concrete can undergo early-age cracking depending on the mix composition, exposure environment, hydration rate, and curing conditions. Understanding the causes and consequences of cracking thoroughly is essential for selecting proper measures to resolve the early-age cracking problem in concrete. This paper will help to identify the major causes and consequences of the early-age cracking in concrete. Also, this paper will be useful to adopt effective remedial measures for reducing or eliminating the early-age cracking problem in concrete. Different types of early-age crack, the factors affecting the initiation and growth of early-age cracks, the causes of early-age cracking, and the modeling of early-age cracking are discussed in this paper. A number of examples for various early-age cracking problems of concrete found in different structural elements are also shown. Above all, some recommendations are given for minimizing the early-age cracking in concrete. It is hoped that the information conveyed in this paper will be beneficial to improve the service life of concrete structures. Concrete researchers and practitioners may benefit from the contents of this paper.

Rapid growth in industrial development has raised the concern of proper disposal of the by-products generated in industries. Many of them may cause serious pollution to the air, land, and water if dumped in open landfills. Agricultural and municipal wastes also cause environmental issues if not managed properly. Besides, minimizing the carbon footprint has become a priority in every industry to slow down global warming and climate change effects. The use of supplementary cementitious materials (SCMs) obtained from agricultural, industrial, municipal, and natural sources can decrease a significant amount of fossil fuel burning by reducing cement production and contribute to proper waste management. Also, SCMs can enhance desirable material properties like flowability, strength, and durability. Such materials may play a big role to meet the need of modern time for resilient construction. The effective application of SCMs in cement-based materials requires a clear understanding of their physical and chemical characteristics. Researchers studied how the flowability, strength, and durability properties of structural mortar change with the replacement of cement with different SCMs. Various experiments were conducted to examine the behavior of structural mortar in extreme conditions (e.g., high temperature). Many scholars have attempted to improve its performance with various treatment techniques. This article is an attempt to bring all the major findings of the recent relevant studies together, identify research gaps in the current state of knowledge on the utilization of SCMs in structural mortar, and give several recommendations for further study. The available results from recent studies have been reviewed, analyzed, and summarized in this article. A collection of the updated experimental findings will encourage and ease the use of various by-products and wastes as SCMs in structural mortar for sustainable construction.