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 What Is Splicing of Reinforcement Bars? 🏷Splicing of reinforcement bars, commonly known as rebars, refers to the process of connecting two or more rebars in a reinforced concrete structure to ensure a continuous and load-resistant structure. 🚧It is a critical practice in construction to transfer the stresses from one bar to another effectively, maintaining structural integrity. 💫Methods of Splicing Reinforcement Bars There are three primary methods of splicing reinforcement bars: ❇️1. Lap Splice A lap splice is the most widely used method in reinforced concrete structures. In this technique, two rebars are overlapped and tied together using binding wires. The overlap length, also known as the lap length, is crucial for ensuring the splice’s strength. ⏺It is determined based on factors such as: • The diameter of the rebars. • The grade of concrete. • The specific application of the structure. ▶️The lap splice is easy to implement and cost-effective but may require additional con...

 Design mix and Nominal mix of concrete A  concrete mix  is a combination of five major elements in various proportions: cement, water, coarse aggregates, fine aggregates (i.e. sand), and air. Nominal Mix These mixes are fixed cement aggregate ratio which ensure adequate strength to the concrete. In the fig. M5, M7.5, M10, M15, M20 and M25 are nominal mixes. Due to variability in mix, they differs in workability and compressive strength. The ratio of mix is required when we estimation of concrete. Design Mix In these mixes the performance of the concrete is specified by the designer but the mix proportions are determined by the producer of concrete, except that the minimum cement content can be laid down. This is most rational approach to the selection of mix proportions with specific materials in mind possessing more or less unique characteristics. In the fig. M30 and above are design mixes.

Compressive Strength of Concrete Cylinders The most common sample type for tests of concrete compressive strength is the concrete cylinder. There are other ways to determine concrete strength, and some methods may be more cost-effective and arguably better, but concrete cylinder testing remains the standard for acceptance. Well-made concrete cylinders are easy and inexpensive to produce. Typically, one technician posted at the point of discharge or point of placement is sufficient to sample and test concrete batches for the slump, air content, unit weight, and cylinders. Technicians must follow standard practices and be certified in most regions, but training is neither extensive nor complex. To determine the compressive strength of concrete cylinders. Apparatus  1) Compressive strength machine Procedure  1) Take out the cylindrical specimen from the curing tank.  2)Wipe out the excess water from the surface of the specimen. 3)Place the specimen vertically on the platform...

  DESIGN PROCEDURES FOR A BUILDING FOUNDATION 1. DECIDE THE LOCATION OF COLUMNS & FOUNDATION AND TYPE OF LOADS ACTING ON THEM.(E.X DEAL LOAD,  LIVE LOAD OR WIND LOAD) 2. ESTIMATE ALLOWABLE BEARING PRESSURE OF SOIL USING GROUND INVESTIGATION REPORT. 3. DECIDE DEPTH OF FOUNDATION 4. CALCULATE FOUNDATION AREA 5. DETERMINE VARIATION IN VERTICAL STRESSES 6. CALCULATE SETTLEMENT 7. COST CONTROL 8. CONSIDER TIME 9. VARIATION IN GROUND CONDITION 1. DECIDE THE LOCATION OF COLUMNS & FOUNDATION AND TYPE OF LOADS ACTING ON THEM.(E.X DEAL LOAD,  LIVE LOAD OR WIND LOAD) On the building plan, the position of columns and load bearing walls should be marked, and any other induced loading and bending moments. The loads should be classified into dead, imposed and wind loading, giving the appropriate partial safety factors for these loads. 2. ESTIMATE ALLOWABLE BEARING PRESSURE OF SOIL USING GROUND INVESTIGATION REPORT. From a study of the site ground investigation (if available), th...

 How can you increase the bearing capacity of soil? bearing capacity is the capacity of soil to support the loads applied to the ground. The bearing  capacity of soil is  the maximum average contact pressure between the foundation and  the soil  which should not produce shear failure in the soil. How do you find the bearing capacity of soil? bearing capacity of soil by  determining the limit of contact pressure between the soil and  the material placed on it . These calculations and measurements are performed on projects  involving bridge foundations, retaining walls, dams and pipelines that run underground. *The following techniques can be used for improving bearing capacity of soil as per the site condition. =>Increasing depth of foundation =>Draining the soil =>Compacting the soil =>Confining the soil =>Replacing the poor soil =>Using grouting material =>Stabilizing the soil with chemicals

 Why do we use steel and not any other metal in concrete B/C- provides all the tensile strength where concrete is in tension     -  provides extra shear strength over and above that of concrete    -    offer a material that is higher in tensile strength    -  Steel is not as easy to mould and shape     Characteristics of steel: High tensile strength : The high tensile strength offered by steel products and especially steel reinforcement makes it ideal to strengthen concrete structures. A  steel reinforced concrete structure  will offer a material that is higher in tensile strength, which will not easily break under high tension as experienced in large structures. High compressive strength : Steel, just like concrete, is resistant to high compression forces present in larger building an structures. Together, steel and concrete make for the perfect material to ensure lasting structures such as building, bridges and...

 A concrete of Grade C20 means that the concrete will have a compression resistance of 20 N/mm² per square millimeter in 28 days. Proportion for grade C20. C20 is 1:2:4 (1 part cement, 2 parts fine aggregate, and 4 parts coarse aggregate.) where as C20 symbolizes a Cylindrical sample in which cement, fine aggregates, coarse aggregates are mixed in such a ratio that its characteristic compressive strength is 20 N/mm² after 28 days of curing. Fig:- Concrete specimen for testing Generally Strength of Cylinder sample= 0.8 x Strength of Cube. example:- M20 is equivalent to C25 M20 means the grade of concrete is defined as the minimum strength of concrete after 28 days. For the M20 Grade of concrete, The letter ‘M’ refers to the mix, and 20 represents the characteristic strength of concrete in MPa or N/mm². The specified characteristic strength of concrete is determined for 150mm size cube at 28 days. The Characteristic Compressive strength of concrete is defined as the strength of conc...

 Dynamic compaction Dynamic compaction involves the controlled impact of a crane hoisted weight, of around 10-12 tonnes, falling in a pre-determined grid pattern to improve loose, granular and mixed soils and fills. Common uses Increase bearing capacity Decrease settlement Mitigate liquefaction Avoid major below-ground obstruction removal Process Dynamic compaction is a ground improvement technique that densifies soils and fill materials by using a drop weight. Advantages ➪ Capable of compacting a wide variety of weak soils ➪ Increased bearing capacity ➪ Reduced settlement ➪ Sustainable technique using limited material import ➪ Can improve soil conditions on marginal sites to the extent that shallow foundations can be used without deep excavation or piling ➪ Removal of compressible, contaminated fills can sometimes be avoided

  Causes and Prevention of Segregation  separation of the constituents of a heterogeneous mixture so that their distribution is no longer uniform.  In the case of concrete, it is the differences in the size of particles and in the specific gravity of the mix constituents that are the primary causes of segregation, but its extent can be controlled by the choice of suitable grading and by care in handling. It is worth noting that a higher viscosity of the fresh cement paste component militates against the downward movement of the heavier aggregate particles;consequently, mixes with low water/ cement ratios are less prone to segregation. 🏗There are two forms of segregation. *In the first, the coarser particles tend to separate out because they tend to travel further along a slope or to settle more than finer particles. *The second form of segregation, occurring particularly in wet mixes, is manifested by the separation of grout (cement plus water) from the mix. With some gr...

  Types of joints in concrete constructions are:  1,Construction Joints  2,Expansion Joints  3,Contraction Joints  4,Isolation Joints 1,construction joint :- A separation provided in a building that allows its component parts to move with respect to each other; a joint where two placements of concrete meet. 2,An expansion joint or movement joint:-  is an assembly designed to safely absorb the heat-induced expansion and contraction of construction materials, to absorb vibration, to hold parts together, or to allow movement due to ground settlement or earthquakes 3,A control joint or contraction   joint :- is a joint that is put in the concrete to control cracking. For example, when they sawcut joints into the concrete pavement, these are control joints. 4,Isolation and expansion joints   accommodate anticipated differential horizontal and vertical movements that occur between a pavement and a structure. Their purpose is to allow movement...

What Is   Segregation ?   Segregation of concrete means  separation of ingredients from design fresh concrete  resulting in the non-uniform mix . More specifically this implies the separation of coarse  aggregates from the mortar because of differences in size, density, shape and other  properties of ingredients in which they are composed. SEGREGATION Segregation is a separation of cement from aggregate This is caused due to improper water cement ratio  This is also caused when concrete is poured about more then 1.5m height

Construction Cost Estimation for Civil Works-Types and Requirements|  Project estimator For the construction of your dream home, the first thing you want to do is check how much money you have in your bank account?.After that, you need to to have a plan and prepare different types of estimation for cost of construction upon your civil works with the help of a project estimator. During this process, the two factors you have to take care is the number of materials and costs of these items.The method of estimating unit cost of an item is called “ Rate analysis ” and the method of obtaining the required quantities of these materials are called “estimation” . In this blog, we are going to learn about types of estimation of and Cost estimation methods.The construction cost estimation can be done with the help of a project estimator.For a construction process, there are different estimation process is involved different stages of construction. What are the Requirements of Estimation an...