Comein

Calculation of the T-section Wall Segment for Load-bearing Capacity and Crack Opening – Rigid Supports

Objective: Check of the calculation of eccentrically compressed columns.

Task: Verify the correctness of the analysis of stability and masonry seam opening under eccentric compression.

References: Reference manual on design of masonry and reinforced masonry structures (supplement to SNiP II-22-81), 1989, p. 20-21.

Initial data file:

1. when the longitudinal force is N = 326 kN:

Example 3.1.SAV;
ComeIn 3.1.doc — report

2. when the longitudinal force is N = 160 kN:

Example 3.2.SAV
ComeIn 3.2.doc — report

Initial data:

е0 = -0,45 m Force eccentricity
Н = 5 m

Storey height
Stone/brick Molded clay brick, grade 100
Mortar Regular cement with mineral plasticizers, grade 50
R = 1,5 MPa Design resistance of masonry
Нf  = 0,22 m Thickness of the precast reinforced concrete floor slab, embedded into wall masonry on the supports

COMEIN initial data when the longitudinal force is N = 326 kN:

Importance factor  γn = 1
Age of masonry - up to a year
Working life is 50 years
Stone/brick - Molded clay brick
Stone/brick grade - 100
Mortar - regular cement with mineral plasticizers
Mortar grade - 50

Structure:

Eccentricity of longitudinal force - 45 cm along the Y axis
Column height 4,78 m
Longitudinal force 326 kN
Factor for sustained load 1

 

Effective height in the XoY plane

Effective height in the XoZ plane

Bracing scheme
Precast floor slabs
Distance between transverse rigid structures 5 m
Effective height factor 0,9

Bracing scheme
Precast floor slabs
Distance between transverse rigid structures 5 m
Effective height factor 0,9

 

COMEIN initial data when the longitudinal force is N = 160 kN:

Importance factor  γn = 1
Age of masonry - up to a year
Working life is 50 years
Stone/brick - Molded clay brick
Stone/brick grade - 100
Mortar - regular cement with mineral plasticizers
Mortar grade - 50

Structure:

Eccentricity of longitudinal force - 45 cm along the Y axis
Column height 4,78 m
Longitudinal force 160 kN
Factor for sustained load 1

 

Effective height in the XoY plane

Effective height in the XoZ plane

Bracing scheme
Precast floor slabs
Distance between transverse rigid structures 5 m
Effective height factor 0,9

Bracing scheme
Precast floor slabs
Distance between transverse rigid structures 5 m
Effective height factor 0,9

 

Comparison of solutions:

Longitudinal force

N = 326 kN

N = 160 kN

Check

stability

masonry seam opening

Theory

326/326 = 1

160/160 = 1

COMEIN

0,958

0,999

Deviation, %

0,398

0,1

 

Comments:

  1. Specific value of the applied longitudinal force is not determined in the problem, therefore ComeIn uses the calculated values of the load-bearing capacity N = 326 kN and N = 160 kN for stability and masonry seam opening respectively.
  2. The column height in ComeIn is taken as the difference between the storey height and the floor slab thickness Н - Нf  = 5 – 0,22 = 4,78 m.
  3. Distance between transverse rigid structures has to be specified in ComeIn. Since it is not determined in the problem, the value of 5 m is used.
  4. Age of masonry has to be specified in ComeIn. Since it is not determined in the problem, the value of "up to a year" is used.