Posts

JOINTS IN CONCRETE STRUCTURES

-
Image
INTRODUCTION In nowadays, reinforced concrete is the most popular construction material, we have  larger reinforced concrete structures spanning over a larger area such as Dams, retaining walls , rigid pavements, concrete channels and buildings; their construction methods involves the use of different kinds of joints so they can function effectively over its designed life. Concrete joints , these are discontinuities that are made within concrete structures or between consecutive concrete structures or structural members so as to allow horizontal movement. THE NEED OF JOINTS Concrete material has one great weakness that is its low tensile capacity, due to its weakness concrete is subjected to cracking where by some of them are unavoidable, so crack control in reinforced concrete structures is needed for two reasons. 1. Aesthetic of concrete structure Structures such as building their aesthetic value is the one of the important aspect during its design and construction, cra
Post a Comment
Read more

TYPES OF RETAIN WALLS

-
Image
INTRODUCTION Retaining walls these are relatively rigid walls designed and constructed for provision of support to soil masses laterally, so that will be prevented from sliding or eroded away. Why we need retain walls or retaining structures On sloping land of earth surface the soil is not stable, lateral forces push soil masses by sliding or eroding form upper land to lower land. Soil is stable when the slope of the surface is flatter than safe slope, on sliding the soil is trying to flatten its surface, when we have limited space it not possible to provide the safe slope and soil is to be retained at a slope steeper than the safe one, here retaining structures comes. Retaining wall can be found in bridges, buildings, flyovers and roads. Types of retaining walls 1. Gravity retaining wall These are retaining walls which their stability against lateral forces from soil mass depend on their weight, usually constructed from plain concrete or masonry, this kind of retaining w
Post a Comment
Read more

TYPES OF ROOFS

-
Image
INTRODUCTION Roof , this is top superstructure part of building, serving to protect building, households and all furniture against rain, snow, sunlight, wind and extreme temperatures. Roofs these are one of important parts of the building, you cannot find buildings without roofs, but what you will find is buildings constructed with different kinds of roofs; in this post you will know different kinds of roofs that you can design and construct in your building project. FUNCTIONAL REQUIREMENTS 1. Weather resistance Roofs are made up of two important parts which are structural part (roof structure) and roof covering, most of structural parts are made of materials which are not weather resistant such as timber and steel. This structure should be covered by roof covering which are weather resistant and impermeable, that they prevent ingress of rainwater, snow and other weather effects into the building. 2. Adequate Drainage Well designed and constructed roof should possess a sloping length t
Post a Comment
Read more

STAIR DESIGN FOR RESIDENTIAL BUILDING

-
Image
INTRODUCTION One of the important components of the building especially for those with more than one floor levels or building constructed at height is stairs . Stairs are building components which allow building users or households to move from one floor level to the other, so it is connector or communication path between floors or levels. Stairs are composed with series of steps at certain inclination angle to allow vertical movements inside and outside the building. Types of Stairs   Stairs can be classified into number of types as depending on its architectural design inside the building, the followings are some types of stairs that can be found in different buildings. Main parts of stairs . The following are standard requirements for each stair component, so as to have comfort and serviceable stair. Landing , this is horizontal slab between two or more  flights, which  is used as resting or changing in direction point. Riser , t is the vertical portion of step, where for comforta
Post a Comment
Read more

PRESTRESSED CONCRETE

-
Image
  INTRODUCTION Hardened concrete as the artificial hard rock that could be designed or made with certain desired shape from casted fresh concrete, has some weaknesses that make it alone unfit for major structures which are the following ·        Have little or negligible strength against tension ·    Brittle property (not ductile), which makes it susceptible to cracking on loading When we design different major structures, there are two important criteria that are put into consideration    Safety of the structure against failure, the structure should be able to carry desired loads for intended period of time.   Serviceability or functional of the structure, where by the structure should neither deflect in extent that it affects comfort ability of users nor lead to detaching or breaking of attached materials such as tiles of curtain walls. Introduction of reinforcements which are ductile or elastic material into concrete, produce reliable composite material against crac
Post a Comment
Read more

COMPACTION OF SOILS

-
Image
INTRODUCTION Soil natural found material from weathering processes of different rocks, soil in construction industry can be used as construction material or natural foundation for different structure erected on it. Soil compaction is most popular and important construction process that is must be performed when working with road layers, embankments and structural beds. Compaction of a road layer using steel roller Compaction of soil is the mechanical process on soil, that is applied to increase density of soil by reducing void spaces between soil particles, compaction as mechanical process can occur either naturally or artificially, naturally this can be seen in soil formation process. There are three things that need be present so that compaction can occur, which are water (lubricant), air voids and compactive effort. Water as the lubricant reduce friction resistance (shear strength) between soil particles, that allow soil particles to be driven or moved into air voids during compacti
Post a Comment
Read more

STRENGTHS OF HARDENED CONCRETE

-
Image
STRENGTH OF CONCRETE Is the property of hardened concrete to resist excessive strains due to induced stresses that could result to its failure, these stresses can be from internal or external factors. Strengths of hardened concrete can be distinguished from one to another regarding to type of stress or load that a concrete is required to resist, as follows 1. Compressive strength This is the ability of hardened concrete to resist compression stresses; the compression strength of concrete is the one which denotes grade of concrete, this is very important strength property of concrete than other strength properties because a). Easy to measure b). Other strength properties such as flexural shear and bond strengths they can be deduced from compressive strength through established correlations. Compression strength of concrete is measured through standard uniaxial compression test, which can be performed on concrete cubes or cylinders. On going compression strength testing of concrete cub
1 comment
Read more