Name: MOHD SHEREEN BIN ZAINUDDIN

Matric no: A136646

INTRODUCTION

Nowadays, the application of rubber bearing is really important to reduce vibration risk due to

earthquake or vibration from human activity. For bridge applications this rubber bearing is used

to protect structural elements from the effects of strong-ground motion. Rubber bearing with

steel reinforcement are mostly common rubber bearing are used in superstructure application.

For this analysis, CST software is used to determine the formation of the deformation of the

rubber block with and without steel laminated at the middle of the rubber block.

Before we proceed with the calculation by using CST, here are some information related with the

acronyms:

NN: Number of node

NE: Number of elements

NM: Number of different materials

NDIM: Number of coordinates per node (2D = 2 or 3D = 3)

NEN: N Number of node per elements

ND: Number of degree of freedom along which displacement is specified. (Boundary condition)

NL: Number of applied component loads (along degree of freedom)

NMPC: Number of Multipoint Constrains

Nu: Poissons ratio

CASE 1:

Rubber block without steel laminated deformation analysis.

Rubber block analysis:

Thickness: 300mm

Dimension: 100 mm X 80 mm

Material: Rubber.

Answer:

Node# X-Displ (mm) Y-Displ (mm)

1 -1.70077E-06 -3.70928E-06

2 6.03003E-07 -4.8504E-06

3 1.51156E-06 -4.37135E-06

4 -0.059250339 -0.16026537

5 0.031269896 -0.139690352

6 0.136115145 -0.238519185

7 -0.030993938 -0.375223348

8 0.074256736 -0.296143672

9 0.267747217 -0.508297224

Elem# SX SY Txy S1 S2 S3

1 -26.70966247 -53.42024646 -4.93746 -25.8262 -54.3037 -10.1447

2 0.857812273 -34.49246932 3.977442 1.299808 -34.9345 6.341018

3 -23.28067469 -46.5617128 2.605806 -22.9926 -46.8498 6.309005

4 -11.79373582 -65.52557143 4.754214 -11.3763 -65.943 5.017608

5 -11.68760037 -59.5832946 3.726368 -11.3994 -59.8715 4.422247

6 1.991293218 -38.11768335 8.854215 3.858931 -39.9853 11.91092

7 1.883179886 -38.17174002 -3.00635 2.107567 -38.3961 -4.26851

8 6.634455171 -64.12728202 -3.17423 6.776559 -64.2694 -2.56331

DOF# Reaction

1 197288.9441 N

2 430276.6238 N

3 -69948.29141 N

4 562646.7523 N

5 -175340.6527 N

6 507076.6238 N

Result:

Displacement of the node:

From the picture above, it is the form of deformation of the rubber block. The resultant force are

more toward to the right direction. The deformation happened at the entire portion of the

element.

CASE 2:

Steel laminated rubber block analysis:

Thickness: 300mm

Dimension: 100 mm X 80 mm

Material: Rubber and steel

Answer:

Node# X-Displ (mm) Y-Displ (mm)

1 -3.89101E-08 -1.12083E-07

2 1.50991E-08 -1.93563E-07

3 3.78997E-08 -1.34624E-07

4 0.002013544 -0.134005283

5 0.021987199 -0.120650501

6 0.041988278 -0.163685533

7 -0.000689064 -0.137619293

8 0.025582289 -0.123865518

9 0.050385789 -0.168204464

10 -0.021151996 -0.309906591

11 0.037200266 -0.229298178

12 0.203999529 -0.406731079

Elem# SX SY Txy S1 S2 S3

1 -25.52477999 -51.04958159 0.191764 -25.5233 -51.051 0.430423

2 -17.65470284 -43.29886792 2.984336 -17.312 -43.6416 6.551153

3 -22.98100492 -45.96201896 2.094021 -22.7918 -46.1513 5.164099

4 -25.84454997 -59.68953154 1.129878 -25.8069 -59.7272 1.909923

5 63.96764559 -53.08992242 -0.24347 63.96815 -53.0904 -0.11917

6 94.28056554 -36.01616334 48.8142 110.5394 -52.275 18.4217

7 66.71891879 -44.28465736 -38.5532 78.79522 -56.361 -17.3925

8 79.23122218 -66.60925688 -3.61752 79.3209 -66.6989 -1.42004

9 -25.81093374 -62.13040893 -1.03193 -25.7816 -62.1597 -1.62618

10 -4.521808037 -32.38452108 6.480368 -3.08834 -33.818 12.47308

11 -13.46814476 -36.85768945 -1.84946 -13.3228 -37.003 -4.49327

12 -0.953837837 -68.62738054 2.80102 -0.8381 -68.7431 2.366088

DOF# Reaction

1 132566.8625 N

2 381865.0992 N

3 -51442.50217 N

4 659469.8016 N

5 -129124.3603 N

6 458665.0992 N

The deformation of the rubber mostly happened at the top layer of the laminated rubber block.

DISCUSSION

1. The displacement of the nodes for case 1 (rubber block without steel laminated) are much

higher compared to the rubber block with steel laminated.

2. Besides that, the reaction forces for case 1 are higher compared to the steel laminated

rubber block.

3. Steel laminated rubber block give out minimum deformation and stabilize the shape of the

block, which is important to maintain the shape of the structure in application area.

4. The deformation of the rubber block without steel laminated give out major shape changing

when force being applied to its surface.

CONCLUSION

As conclusion, for steel laminated rubber block, the deformation happen mostly at the top of the

surface of the laminated area. But for the rubber block without steel laminated, we can see that,

the entire area of the surface undergoes serious deformation.