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A rectangular RCC machine foundation of size 3.0 x 3.0 x 0.8m thick is supporting a machine of weight is 10kN. The machine transmits an unbalanced vertical load passing through the combined CG of the machine and foundation whose amplitude is 8[1-sin/4t]kN Soil medium has the following properties: Young’s modulus, E=1.2 x105 kN/m2 . Poisson’s ratio, v=0.3. Unit weight of soil and concrete, s=17 kN/m3 . c=17 kN/m3 Find the response of the system and natural frequency using Elastic half- space approach for vertical and sliding vibration

User Dparnas
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Final answer:

The response involves calculating normal stress and strain in materials subjected to weights and forces, including a steel rod, a granite pillar, and the torque on a beam due to an off-center mass, as well as evaluating the potential bending and compression of a pole and the force exerted by expanding grape juice.

Step-by-step explanation:

The questions involve determining the normal stress and strain within materials subjected to external loads. Specifically, the questions include calculating the stress in a cylindrical steel rod and a granite pillar, finding the torque on a beam, understanding the bending and compression of a pole supporting a weight, and analyzing the force exerted by expanding grape juice.

Additionally, questions address calculating the maximum acceleration of a utility truck and evaluating the energy stored in a damping system and the energy required to oscillate a suspension bridge.

The normal stress in an object is found by dividing the force exerted by the object's cross-sectional area. For the cylindrical rod and the granite pillar, the weight of the material above the cross-section provides the force. To find torque, apply the relationship that torque equals force times the distance to the pivot point.

Bending and compression of materials can be derived from mechanical and material properties such as tension and stiffness. The expansion of liquids and the related forces can be estimated using the bulk modulus property of the material.

User Wiebe Tijsma
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