w- armer moments
 

w- armer moments
what is wood and armer moments in reinforced concrete slabs idealised as grillages.
wood armer is an equivalent moment method - it basically takes the mxy (twisting) moment and lumps this value to the principal direction moments mx & my.
a ref for this is r.h.wood 鈥?鈥濼he reinforcement of slabs in accordance with a pre-determined field of moments鈥? concrete, february 1968
a
to use the wood-armer equations for reinforcement calculations, as follows:
a) mx, my, and mxy are fetched or calculated, as described above. they are used to compute the values of design moments, mxd and myd.
b) for top reinforcement, the program computes:
mx1 = mx + abs(mxy)
my1 = my + abs(mxy)
mx2 = mx + abs(mxy2 / my)
my2 = my + abs(mxy2 / mx)
if both mx1 and my1 are positive, mxd = mx1 and myd = my1.
if both mx1 and my1 are negative, mxd = 0 and myd = 0.
if mx1 is negative and my1 positive, mxd = 0 and myd = my2.
if my1 is negative and mx1 positive, mxd = mx2 and myd = 0.
c) for bottom reinforcement:
mx1 = mx - abs(mxy)
my1 = my - abs(mxy)
mx2 = mx - abs(mxy2 / my)
my2 = my - abs(mxy2 / mx)
if both mx1 and my1 are positive, mxd = 0 and myd = 0.
if both mx1 and my1 are negative, mxd = mx1 and myd = my1.
if mx1 is negative and my1 positive, mxd = mx2 and myd = 0.
if my1 is negative and mx1 positive, mxd = 0 and myd = my2.
mxd and myd are then used in lieu of mx and my for calculations of the required reinforcing.