This article is concerned with how masonry is built, the architectural forms used and the resulting appearance. The basic structural form of many types of masonry is expressed on the surface of buildings and other structures and can be a very attractive and reassuring aspect of these. Appearance is a synthesis of the size, shape […]
Compressive Strength of Masonry Walls Axial loads Masonry is most effective when resisting axial compressive loads normal to the bedding plane. This is, clearly, the way in which most load-bearing walls function but also the way that arches and tunnels resist load since an inward force on the outside surface of a curved plate structure
Viscosity of Bituminous Materials Viscosity and Rheology of Binders The viscosity of a liquid is the property that retards flow, so when a force is applied to a liquid, the higher the viscosity, the slower will be its movement. The viscosity of bitumen is dependent upon both its chemical make-up and its structure. In sol-type
Deformation of Bituminous Materials Resistance of Bitumen to Deformation Since bitumen is a viscoelastic material, the response to an applied load depends on the size of the load, the temperature, and the duration of its application. In other words there is no simple relationship between stress and strain and it is therefore difficult to predict
Strength and Failure of Bituminous Materials The Road Structure A flexible road structure consists of a number of layers of different materials. In structural terms, the purpose of the road is to distribute the applied load from the traffic to a level that the underlying subgrade can bear. The stresses induced by the loads are
Durability of Bituminous Structures Durability is the ability to survive and continue to give an acceptable performance. In the case of roads, it is necessary that the structure should survive for the specified design life, although it is accepted that not all aspects of performance can be sustained for this duration without some restorative maintenance.
Bituminous Mixtures There are a very large number of bituminous mixtures, which vary according to density, bitumen content, bitumen grade, aggregate size and aggregate grading. Previously in the UK these mixtures used to be classified into two groups, namely ‘asphalts’ and ‘macadams’. The move to European standardisation has meant that bituminous mixtures are now classified
Recycling of Bituminous Materials The recycling and reuse of bituminous materials is not a recent development, the first asphalt pavement recycling project being recorded in 1915 (Epps et al., 1980). Recycled (or reclaimed) asphalt pavement (RAP) material consists of aggregate and bitumen that has been removed and/or reprocessed from an asphalt pavement. Although old asphalt
Basic Terminology Units: brick or block-sized pieces of stone, fired clay, concrete or calcium silicate bonded aggregate that are assembled to make masonry. Usually, but not invariably, these are in the form of rectangular prisms, but many special shapes are manufactured and stones are often used either as found or shaped to be partly squared,
Properties of Mortar Mortar has to cope with a wide range of sometimes conflicting requirements. To obtain optimum performance the composition must be tailored to the application. The broad principles are as follows: Mortars with a high content of hydraulic cements are stronger, denser, more impervious and more durable, bond better to units under normal