特刊"建筑材料和其他相关材料:基本理论,应用技术和先进研究方法 (第二版) "

Prestressed concrete is a construction technique designed to enhance the strength and durability of concrete structures. This method involves the application of a pre-set tension to high-strength steel strands used as reinforcement before the concrete is subjected to its working loads. The primary aim of prestressing is to place the concrete in a state of compression, in order to counteract the tensile forces it will experience in service. This pre-compression helps prevent crack formation in...

Deleterious substances in aggregates can be detrimental to the quality and durability of concrete. These substances include organic impurities like loam, which interfere with cement hydration and are usually present in the sand. These prevent a good bond between aggregate and cement paste. Organic impurities can be detected using the colorimetric test, where the darkness of a solution after agitation indicates the level of organic content.
Another type of impurity is clay and fine material that...

Mass concreting refers to the process of placing large volumes of concrete, such as in gravity dams. The heat generated during the cement hydration process and differential cooling rates within the concrete mass can lead to a temperature gradient, which can result in thermal cracks in the concrete mass.
To reduce the risk of such cracking, the concrete mix may incorporate low-heat cement and pozzolans to reduce the temperature rise. Pre-cooled angular aggregates and water-reducing admixtures...

Ferro-cement is a distinctive construction material that represents an innovative variant of reinforced concrete, characterized by its unique composition and the method by which it is formed. Unlike standard reinforced concrete, which relies on larger steel bars for reinforcement, ferro-cement utilizes densely packed layers of mesh or fine rods, fully encased in cement mortar. This composition allows for the creation of structures that are significantly thinner and more flexible than their...

Concrete is a vital construction material extensively used worldwide, primarily valued for its strength, durability, and versatility, which it provides for various structural designs. Concrete generally comprises ingredients like Portland cement, coarse gravel, fine sand, and water. Concrete can be mixed by simple hand methods or industrially at computer-controlled plants. The mixture consists of aggregates and a paste made from water and Portland cement. This paste coats the aggregates and,...