Author: Mezie Ethelbert

Reading Time: 6 minutes Layered flexible bituminous pavement has been identified as the most common type of pavement used for urban and rural roads around the world. During the design process of these roads, certain design period (identified as structural design period – SDP) is applicable. The design period is defined as the period during which the road is expected to carry traffic at a satisfactory level of service, without requiring major rehabilitation or repair work (though certain maintenance may be carried out during the period to keep the road in good service condition). The design period is often chosen while considering individual wheel…

Reading Time: 2 minutes Excessive noise within the vicinity of buildings is very undesirable because, in addition to the normal discomfort that it causes, it can lead to a range of health issues such as anxiety, depression, high blood pressure, heart disease, hearing loss, etc. This is often the reason why commercial and industrial hubs are usually located at appreciable distances away from residential areas. Noise is usually measured in decibels (dB) which is used to express the level of hearing. The threshold of hearing falls within 0 dB upwards while 130 dB upwards is identified as the threshold of pain. This implies that…

Reading Time: 3 minutes U-values, R-values, and K-values are known as thermal coefficients in buildings. To insulate the interior of buildings against high external temperatures, it is necessary to ensure that the materials used in making the heat transmitting mediums in buildings such as walls, windows, doors, plasters, partitions etc. are well insulated. This insulation is more important at this critical stage where the world is experiencing global warming which is due to large amounts of entrapped heat on the earth’s surface due to large concentrations of greenhouse gases on the surface. The insulation capacities or heat transfer capacities of exposed elements of building…

Reading Time: 3 minutes Step 1: Determination of Annual Average Daily Traffic (AADT) The first step to determine the design traffic loading over the design life of a pavement is to determine the baseline traffic flows. The estimate of the baseline traffic flows should be the Annual Average Daily Traffic (AADT) or Average Daily Traffic (ADT) currently using the ruote (if an existing ruote), or expected to use the route on opening to traffic (if a new ruote), classified into vehicle categories (See FHWA vehicle categories): Federal Highway Administration (FHWA) Vehicle Classes Motorcycles Passenger Cars 4 – Tyre Trucks Buses 2 – Axle 6-Tyre…

Reading Time: 2 minutes Statically determinate frames are analysed in the same manner as ordinary beams. The support reactions are determined from three equations of static equilibrium. For three hinged frames, an additional equation which gives the summation of the moments of the hinge is zero is utilized. The bending moments which cause tension on the internal side of the frame shall be regarded as positive and the graph is plotted on the tensile side of the frame. The graph of the +ve shears are plotted on the exterior side while the -ve shears are plotted on the interior side. Procedure for Analysis Draw…

Reading Time: 8 minutes A geotechnical test report is provided at the end of geotechnical investigation or subsurface soil exploration and they are very important in civil engineering works. The purpose of the investigation is to obtain information as outlined below: Determining the nature of the soil at the site and its stratification. Selecting the type and depth of foundation suitable for a given structure. Evaluating the load-bearing capacity of the foundation. Estimating the probable settlement of a structure. Determining potential foundation problems (e.g., expansive soil, collapsible soil, sanitary landfill, etc…). Determining the location of the water table. Determining the depth and nature of…

Reading Time: 6 minutes Components of HSE Management Health, Safety, and Environmental management should be part of the engineering profession in  a country  for  the  purpose of:  (a) Duty of care (b) Economic reasons and (c)  Legal reasons. HSE management should therefore consider five broad phases: (i) Specifications (ii) Design and implementation (iii)  Installation and commissioning (iv) Operation and maintenance (v) Changes after commissioning. Compliance with the standards requires four essential elements: (a)  Identification of safety functions required for the safe shutdown. (b) Assignment of a safety integrity level (SIL) for each safety function. (c) Use of the safety lifecycle for the engineering design…

Reading Time: 2 minutes In engineering circles, it is believed· and accepted that there is nothing like a failure-proof design. There is always the possibility of failure associated with engineering designs.  Risk analysis is an essential component of environmental designs so that environmental engineers work with risk and probability of failure in all areas of their profession. Engineers have both a moral and often legal obligation to ensure that the risks of their designs are well-known and understood. They thus have an obligation to minimize risk wherever possible.  They also need to be aware of the consequences of their designs and to make these…