Paddy Engineering Consultant

In large work or in major construction works, cement is generally stored at site. The cement must be stored in such a manner so that, it can be easily accessible for proper inspection. The building in which cement is stored should be water tight in order to prevent dampness. The guidelines given below should be observed while storing the cement. 1. Cement should not be stored for a long period. During rainy season, the storage time period of cement should be as minimal as possible. 2. Dampness in godowns must be avoided. 3. Cement should not be piled against the wall. A minimum space of 60 cm all –round should be left between the exterior walls and the stacks. The distance between two consecutive stacks should be minimum to reduce circulation of air. 4. Cement should not be piled directly on the floor; instead it should be piled off the floor on wooden planks/crates so as to be clear off the floor by at least 10 to 20 cm. 5. There should not be more than 15 bags in one pile. This...

ADVANTAGES OF PRECAST CONCRETE Following are the advantages of precast concrete: 1. The concrete of superior quality is produced as it is possible to have better technical control on the production of concrete in factory. 2. It is not necessary to provide joints in the precast construction. 3. The labour required in the manufacturing process of the precast units can easily be trained. 4. The moulds employed for preparing the precast units are of steel with exact dimension in all directions. These moulds are more durable and they can be used several times. 5. The precast articles may be given the desired shape and finish with accuracy. 6.The precast structures can be dismantled, when required and they can then be suitably used elsewhere. 7. The transport and storage of various components of concrete for cast in-situ work are eliminated when precast members are adopted. 8. The work can be completed in a short time, when precast units are adopted. 9. When precast structures are to be ins...

The following properties of soil are taken into consideration while dealing with soil as a construction material. Cohesion  Angle of internal friction  Capillarity  Permeability  Elasticity  Compressibility  1. COHESION It is the internal molecular attraction which resists the rupture or shear of a material. Cohesion is derived in the fine grained soils from the water films which bind together the individual particles in the soil mass. Cohesion is the property of the fine grained soil with particle size below 0.002 mm. cohesion of a soil decreases as the moisture content increases. Cohesion is greater in well compacted clays and it is independent of the external load applied. 2. ANGLE OF INTERNAL FRICTION The resistance in sliding of grain particles of a soil mass depends upon the angle of internal friction. It is usually considered that the value of the angle of internal friction is almost independent of the normal pressure but varies with the de...

The choice of whether a structure should be built of concrete, steel, masonry, or timber depends on the availability of materials and on a number of value decisions. 1. ECONOMY Frequently, the foremost consideration is the overall cost of the structure. This is, of course, a function of the costs of the materials and the labour and the time necessary to erect them. Concrete floor systems tend to be thinner than structural steel systems because the girders and beams or joists all fit within the same depth, or the floors are flat plates. This produces an overall reduction in the height of a building compared to a steel building, which leads to a; a. Lower wind loads because there is less area exposed to wind b. And savings in cladding and mechanical and electrical risers Frequently, however, the overall cost is affected as much or more by the overall construction time since the contractor and the owner must allocate money to carry out the construction and will not receive a retu...

FAILURE OF SHALLOW FOUNDATION & PREVENTIVE MEASURES The major causes of foundation failures are as follow Unequal settlement of sub soil Unequal settlement of masonry Presence of expansive soil below foundation Presence of mature trees Seasonal changes 1. UNEQUAL SETTLEMENT OF SUB SOIL This is one of the most important reasons for foundation failure. Unequal settlement causes cracks in the foundation and ultimately leads to failure of the whole structure. Unequal settlement of the foundation generally occurs for the following reasons The sub soil may not be uniform throughout the site. This means if some part of the site consist of compressible soil (such as clay) and some part consist of hard stratum (such as rock). The load coming from the structure may not be uniform. It may occur also on building constructed on sloping ground. REMEDIES The foundation should be designed in such a way that the pressure on soil on different portions of the structure and correspondi...

PROPERTIES OF MORTAR Properties of mortar which are sought for use in masonry are: workability, water retentivity, rate of stiffening, strength, resistance to rain penetration and durability. These properties have been discussed below explaining their effect on masonry. Choice of masonry mortar is governed by several considerations such as: Type of masonry unit and its properties, Degree of exposure to weather and environments, Strength requirements, etc. 1.  WORKABILITY Workability is the property of mortar which enables it to be spread and applied to masonry unit with ease. It also facilitates proper filling of joints in masonry. A good mortar would hang from the trowel and will flow down readily when lightly jerked. This property of mortar depends on properties of various ingredients used for making mortar and on the method of mixing adopted. As a general rule, a mud mortar prepared from fine clay soil has better workability than one prepared from sandy soil and a lime mort...