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http://www.roymech.co.uk/Useful_Tables/Beams/Strain_Energy.html Strain Energy The external work done on an elastic member in causing it to distort from its unstressed state is transformed into strain energy which is a form of potential energy.  The strain energy in the form of elastic deformation is mostly recoverable in the form of mechanical work. Nomenclature c = distance from neutral axis to outer fibre(m) E = Young's Modulus (N/m 2 ) F = Axial Force (N) G = Modulus of Rigidity (N/m 2 )(m) I = Moment of Inertia (m 4 )(m) l = length (m) M = moment (Nm) V = Traverse Shear force Force (N) x = distance from along beam (m) z = distance from neutral (m) γ = Angular strain = δ/l δ = deflection (m) τ = shear stress (N/m 2 ) τ max = Max shear stress (N/m 2 ) θ = Deflection (radians) Strain Energy Pure Tension and compression Strain Energy Pure Torsion Strain Energy Direct Shear Alternatively allowing z to be a variable:....

Types of Joints in Concrete Constructions Types of joints in concrete constructions are: Construction Joints Expansion Joints Contraction Joints Isolation Joints Construction Joints in Concrete Construction joints are placed in a concrete slab to define the extent of the individual placements, generally in conformity with a predetermined joint layout. Construction joints must be designed in order to allow displacements between both sides of the slab but, at the same time, they have to transfer flexural stresses produced in the slab by external loads. Construction joints must allow horizontal displacement right-angled to the joint surface that is normally caused by thermal and shrinkage movement. At the same time they must not allow vertical or rotational displacements. Fig.1 summarizes which displacement must be allowed or not allowed by a construction joint. Fig.2: Types of Construction Joints in Concrete Structures Expansion joints in Concr...

The amount of thermal expansion and contraction of concrete varies with factors such as type and amount of aggregate, richness of mixture, water-cement ratio, temperature range, concrete age, and degree of saturation of concrete. A typical value of thermal expansion and contraction of concrete is on the order of 10 millionths per degree Celsius, that is, very near the same as that for steel. If an unrestrained slab or wall 30 meters long has a temperature variation from summer to winter of 38 degrees Celsius, the total thermal movement might be about 1.5 to 1.8 centimetres. Movements occur at the exposed surface of the concrete, which cools off more quickly, before they occur in the interior of the section, leading frequently to additional warping or curling effects. Observations of buildings in service indicate the total movement is usually less than half of that which might be anticipated by combining the contraction due to temperature drop with the shrinkage. This is ...

CIVIL ENGINEERING ALL COLLECTION ​ SPREADSHEETS A spreadsheet is a computer application that simulates a paper worksheet where becoming increasingly popular in solving engineering related problems. Among the strong features of spreadsheets are their instinctive cell-based structure and easy to use capabilities. Excel, for example, is a powerful spreadsheet with VBA robust programming capabilities that can be a powerful tool for teaching civil engineering concepts. Spreadsheets can do basic calculations such as cost estimates, schedule and cost control, and markup estimation, as well as structural calculations of reactions, stresses, strains, deflections, and slopes. Spreadsheets can solve complex problems, create charts and graphs, and generate useful reports. This paper highlights the use of Excel spreadsheet and VBA in teaching civilengineering concepts and creating useful applications. Civilax provide Excel Spreadsheets for Civil & Structural Engineers for struct...

hypo center ဆိုတာ ငလ်င္လွုပ္တဲ့ေနရာ သူရဲ႕အေပၚတည္႕တည္႕မွာ epicenter ရွိတယ္ ျဖစ္သြားတဲ့ အက္ကြဲေၾကာင္းကို faults plain လို႕ေခၚတယ္ ။ observation ကေန hypocenter and epicenter ၾကားကို dip angle လို႕ေခၚတယ္ ။ hypo center and epicenter ထိအကြာအေ၀းကို focal depth လို႕ေခၚတယ္ ။ observation ကေန epicenter ကို epicentral distance လို႕ေခၚတယ္ ။ မုိင္ ၄၀ shallow earthquake မုိင္ ၄၀ ကေန ၁၉၀ ထိဆိုရင္  intermediate earthquake မိုင္ 450 ကေနအထက္ဆိုရင္ deep earthquake လို႕ေခၚတယ္ ။ Shallow earthquakes are between 0 and 70 km deep; intermediate earthquakes, 70 - 300 km deep; and deep earthquakes, 300 - 700 km deep. In general, the term "deep-focus earthquakes" is applied to earthquakes deeper than 70 km. All earthquakes deeper than 70 km are localized within great slabs of lithosphere that are sinking into the Earth's mantle. ကမ္ဘာေျမၾကီးေအာက္မွာ ရွိတဲ့ ေက်ာက္ေတြက စြမ္းအင္ေတြကို သိမ္ထားတယ္ ။ တခ်ိန္ခ်ိန္မွာ မသိမ္းနုိင္ေတာ့ပဲ ultimate ကို ေက်ာ္ျပီးေပါက္ကြဲရာက ေျမ...

Displacement ကို height နဲ႕စားထားတာကို Drift ratio လို႕ေခၚတယ္ Story drift ratio Story drift ကို story height နဲ႕စားထားကိုေျပာတာ ပထမ Story နဲ႕ ကပ္လ်ပ္ story မွာရွိေနတဲ့ ျခားနားခ်က္ကို သူတို႕ႏွစ္ခုရဲ႕ height နဲ႕စားထားတာကို ေျပာတာ။ (D2-D1)/(h) Dxe and Dx ဆိုျပီးႏွစ္ခုရွိတယ္ တစ္ခုက Elastic ျဖစ္ျပီး တစ္ခုက inelastic ျဖစ္တယ္။ Dxe*cd/I where I is important factor Important factor ဆိုတာ လူေနထိုင္မူေပၚမူတည္ျပီး သက္မွတ္ထားတဲ့ factor ေတြကိုေျပာတာ Cd က deflection amplification factor လို႕ေခၚတယ္ ASCE and IBC မွာရွိတဲ့ တန္ဖိုးေတြနဲ႕တြက္နုိင္။