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 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...

Setting of cement and Hardening of cement The term ‘ Setting ’ is used to describe the stiffening of the cement paste. Setting of cement refers to changes of cement paste from a fluid to rigid state. Setting differs from Hardening of cement. For concrete setting is defined as the phenomenon by which it acquire its shape as per the support inside which it is molded. It is the state from which it enters into amorphous state from plastic state. At setting state if we remove suppose it holds its position for a while but internal crack and deformation start to surface because of absence of strength The term ‘ Hardening’ refers to the gain of strength of a set cement paste, although during setting the cement paste acquires some strength. Hardening or stiffening: It happens after setting state. It is the phenomenon by which hydration of silicate compound occurs in concrete. That means it gains strength. After stiffening, in the case of removal of support it can hold its shape without crack an...

you model the soil using Area spring/spring properties and the software will capture the interaction between the foundation element and the soil. This approach will give you a better understanding and design moment or shear specially for mat foundations. I have some tips: Tip 1: In the absence of plate load test result you can use an approximate method to determine the soil su bgrade reaction. Bowels has proposed the following equation, Ks=40*SF*σall (SF-safety factor, σall allowable bearing capacity). Tip 2: don’t reinforce your mat or footings with the maximum moment around columns. Since the design moment is located at the face of column, at least try to read the moment at the face of column. Otherwise you would reinforce your mat for peak moment and end up being uneconomical. Tip 3: don’t forget to model the lateral passive earth pressure preventing your footing from sliding. Otherwise your model would be unstable. Tip 4: If you are using SAFE, you can model the soil with “soi...

COVER TO REINFORCEMENT ✔️ COVER TO REINFORCEMENT   ES EN 1992-1-1:2014 Definition of cover according to this code is " the concrete cover is the distance between the surface of the reinforcment  closest to the nearest concrete surface". ( ES EN 1992-1-1:2015 Article 4.4.1.1 )  "The nominal cover shall be specified on drawings." ( ES EN 1992-1-1:2015 Article 4.4.1.1[2]) Cₙₒₘ=Cₘᵢₙ+ΔCdₑᵥ  (ES EN 1992-1-1:2015, equation 4.1) Where :- Cₙₒₘ is the nominal cover Cₘᵢₙ is the minimum cover ΔCdₑᵥ is allowance in design deviation. I. Minimum cover( Cₘᵢₙ ) The minimum cover shall be provided in order to ensure( ES EN 1992-1-1:2015 Article 4.4.1.2[2])  the safety transmission of bond forces 1 the protection of the steel against corrosion. 2 an adequate fire resistance 3 the greater of value of Cₘᵢₙ satisfying both bond and environmental conditions shall be used ( ES EN 1992-1-1:2015 ARTICLE 4.4.1.3[2])  Cₘᵢₙ= max {Cₘᵢₙ,b ; Cₘᵢₙ,dᵤᵣ+ΔCdᵤᵣ,γ-ΔCdᵤᵣ,st- ΔCdᵤᵣ,add; 10 mm ...

The term ‘ Setting ’ is used to describe the stiffening of the cement paste. Setting of cement refers to changes of cement paste from a fluid to rigid state. Setting differs from Hardening of cement. For concrete setting is defined as the phenomenon by which it acquire its shape as per the support inside which it is molded. It is the state from which it enters into amorphous state from plastic state. At setting state if we remove suppose it holds its position for a while but internal crack and deformation start to surface because of absence of strength The term ‘ Hardening’ refers to the gain of strength of a set cement paste, although during setting the cement paste acquires some strength. Hardening or stiffening: It happens after setting state. It is the phenomenon by which hydration of silicate compound occurs in concrete. That means it gains strength. After stiffening, in the case of removal of support it can hold its shape without crack and deformations. cement and har...