In the flexibility matrix method of analysis, the values of redundant forces necessary to ensure geometric continuity of structure are determined by using relation (displacement at release due to applied loading = D_p; flexibility matrix = F; redundant forces on released structure = X_R)

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MPPSC AE CE 2017 Official Paper - II

Answer 1

Explanation:

The difference between the flexibility matrix and stiffness matrix is as follows:

Flexibility matrix	Stiffness matrix
1). Elements are determined by applying unit force in the direction of any coordinate and calculate the displacement of the desired coordinate.	1). In this, we identify the unknown joint displacement and fix them and later permit deflection in the coordinate direction and calculate force developed in the various coordinate direction
2). Elements of the flexibility matrix are displacement	2). Elements of stiffness matrix are forces
3). Kij is an element of the flexibility matrix which means the displacement of the direction I due to the unit load in the direction j	3). Kij is any element of stiffness matrix which means, force at point i due to unit deformation at point j
4) {Dp} + [F] {XR} = 0 Where, Where X_R is the load (load) vector, F is flexibity matrix, D_P is the displacement vector	4) {X_R} + [K] {D_P} = 0 Where, Where XR is the load (load) vector, K is the stiffness matrix, DP is the displacement vector