Manufacturing Techniques for Polymer Composites Used in Construction The two parts of this article concentrate upon the manufacturing techniques for civil engineering fibrereinforced thermosetting and thermoplastic polymer composites, respectively. Manufacture of fibrereinforced thermosetting composites There are three basic techniques used to manufacture advanced polymer composites for the civil engineering industry; each technique will have an […]

Fibres for polymer composites When a load is applied to a fibre-reinforced composite consisting of a low-modulus matrix reinforced with high-strength, high-modulus fibres, the viscoelastic flow of the matrix under stress transfers the load to the fibre; this results in a high-strength, high-modulus material that determines the stiffness and strength of the composite and is

Properties of Polymers Mechanical Properties  Thermoplastic polymers, which are not cross-linked, derive their strength and stiffness from the properties of the monomer units and their high molecular weight. Consequently, in crystalline thermoplastic polymers there is a high degree of molecular order and alignment, and during any heating the crystalline phase will tend to melt and

Polymers are produced by combining a large number of small molecular units (monomers) by the chemical process known as polymerisation to form long-chain molecules. There are two main types. Thermoplastics consist of a series of long-chain polymerised molecules, in which all the chains are separate and can slide over one another. In thermosetting polymers the

Conservation of Masonry Conservation of the built environment is a difficult subject to cover comprehensively because it involves a complex interplay between politics, history, legislation, sustainability, the construction arts and crafts, materials science and structural engineering. In this short article only a flavour can be conveyed and an indication of where to look for more

There are a large number of mechanisms by which masonry structures can deteriorate; these can be categorised into: Chemical/biological attack on either the mortar or the units or both, due to water and waterborne acids, sulphates, pollution and chemicals released by growing plants. Corrosion of embedded metal (usually steel) components, particularly ties, straps, reinforcing rods,

The main non-structural function of masonry elements is as a cladding to buildings and the key function of such elements is to maintain habitable conditions within the building. It is therefore important to know how effective masonry wall systems are at preventing heat loss in winter and maintaining comfortable conditions in summer, preventing ingress of

Structural Behaviour and Movement of Masonry Like any structural material, masonry must resist loads or forces due to a variety of external influences (or actions) and in various planes. Figure 1 illustrates the various forces that can arise and the likely actions. In this chapter we will discuss the behaviour of masonry under all these