Advanced Methods of Structural Analysis

Problems 141

P 1 =18kN

a 2 =22m

a 1 =10m

l=30m

P 2 =15kN

A c=3m

B

a 1

a (^0) a 2
2
1
j
Fig. P5.1
5.2.The cable is subjected totwo concentrated forcesPD 30 kN at jointsEand
C, and unknown forceNat jointD, as shown in Fig.P5.2. The thrust of the cable
structure isH D 60 kN. Determine the forceNand corresponding shape of the
cable, if the portionCDof the cable is horizontal.
5m 5m 5m 5m
P
P N
A
C D
E B
fE fC fD=fC 6m
Fig. P5.2
Ans.ND 18 kN;fED5:0m.
5.3.The cable with support points on the same levels has spanlD 36 m is subjected
to uniformly distributed loadqD 2 kN=m along horizontal projection of the cable.
The sag of the cable isf D 6 m. Determine the thrust of the cableH,maximum
axial tensionNmaxand slope at the support.
Ans.HD 54 kN;NmaxD64:89kN
5.4.The cable with support points on the same levels has spanlD 36 mandis
subjected to uniformly distributed loadqD 2 kN=m along horizontal projection of
the cable. The thrust of the cable isHD 108 kN. Determine the sag of the cable,
maximum axial tensionNmax, and slope at the support.
Ans.fD 3 m;NmaxD113:84kN
5.5.The cable with support points on the same levels is subjected to uniformly
distributed loadqalong horizontal projection of the cable. The span of the cable
isl.Ifloadqincreases by two times, but the sagfremains the same, then