Boring Methods of Exploration The boring methods are used for exploration at greater depths where direct methods fail. These provide both disturbed as well as undisturbed samples depending upon the method of boring. In selecting the boring method for a particular job, consideration should be made for the following: The materials to be encountered … Read more
Selection of Hill Road Alignment The main factors to be considered while deciding the alignment of hill roads, are given below. 1.Length The cost of construction of a hill road per kilometer length is comparatively very high. It should therefore be ensured that length of the road connecting two stations should be minimum possible, adopting … Read more
Selection of Material for D.P.C. Any materials to be used as D.P.C must possess following properties. They should be impervious strong and durable to register loads dimensional is stable free from Salt Lake sulfates chlorides and nitrates There are commonly 4 types of materials that can be used at DPC Flexible material (Bitumen felts, plastic … Read more
Dampness in Building Dampness in building is one of the important aspects to consider during building design. Because if neglected, it will affect the building structure adversely and will create unhygienic condition for the persons living in that building. 3 Primary Causes of Dampness in Building Penetration of water into the building components (such as … Read more
Types of Retaining Structure From the point of view of the source from which the retaining structure derives its stability, we have basically two types of retaining structures, viz., the gravity and the non-gravity types. The gravity type structures are normally ‘rigid’ and the non-gravity type, ‘flexible’. The gravity type of retaining structure derives its … Read more
Classification of Traffic Signals Traffic signals are the control devices which alternately direct the traffic to stop and proceed at intersections using red and green traffic light signal automatically. The signals are classified into the following types: Traffic Control Signals Fixed time signals Manually operated signals Traffic actuated (automatic) signals Pedestrian signals Special traffic signals … Read more
Causes of Stone Deterioration The various natural agents such as rain, heat, etc. and chemicals deteriorate the stones with time. 1.Rain Rain water acts both physically and chemically on stones. The physical action is due to the erosive and transportation powers and the latter due to the decomposition, oxidation and hydration of the minerals present … Read more
Pipes for Water Supply System Pipes which are commonly used in water supply system are given below. Cast Iron (CI) Pipes Steel Pipes Galvanized Iron (GI) Pipes Copper Pipes Plastic or Polythene or PVC pipes Asbestos Cement (AC) Pipes Concrete Pipes 1. Cast Iron Pipes These pipes are most commonly used in water distribution system … Read more
Technical Terms Used in C.P.M [Critical Path Method] The following technical terms need be understood clearly before constructing the CPM network 1. Activity An activity is a part of the project denoted by an arrow on the network. The tail of the arrow indicates the start of the activity whereas the head indicates the end … Read more
Defects in Paint Work The defects which are commonly found in paint work are as follow. 1. Blistering Formation of bubbles like shapes on the painted surface is known as blistering. The primary cause of this defect is water vapor. When water vapor trapped under the paint layer, it creates bubbles under the film of … Read more