Electrical University Civil Engineering Mechanics Online Assignment 04 Task Who has the answer to se

Is the answer to mechanics on the first floor?

1. One-way multiple-choice questions (1 point for each question, 13 points in total).

1.Which of the following foundations is NOT an artificial foundation (a). [Chapter I].

a.Quaternary sedimentary soil foundation.

b.Replace the gravel foundation.

c.Strong compaction of clay foundations.

2.In general high-rise buildings, the cost of foundation works accounts for about (b) of the total cost. [Chapter I].

Among the following three clay minerals, (a) soil with high content has the highest plasticity. [Chapter II].

a.Montmorillonite.

b.Illite.

c.Kaolinite.

4.For soils with continuous gradation, (wide answer and c) good gradation. [Chapter II].

5>55.The soil that satisfies condition (b) is the soil with good gradation. [Chapter II].

Lift 5, cc > 3 6

5，cc=1~3

5，cc>2~5

6.If the foundation is regarded as a homogeneous semi-infinite body, the soil can only produce (a) under its own weight. [Chapter III].

a.Vertical deformation.

b.Lateral displacement.

c.Shear deformation.

7.The unidirectional eccentric load acts on the rectangular foundation, and when the eccentricity E satisfies the condition (c), the base pressure is trapezoidal. (l is the side length of the eccentric direction of the rectangular foundation) [Chapter 3].

In the soft and hard double-layer foundation on the top 6, the additional stress in the soil layer is compared with the homogeneous soil, and there is a phenomenon of (a). [Chapter III].

a.Stress concentration.

b.Stress diffusion.

c.The stress is constant.

9.Among the three parts of soil compression, (c) accounts for the largest amount of compression. [Chapter 4].

a.Solid soil particles are compressed;

b.Water and enclosing gas in the soil are compressed;

c.Water and gas are squeezed out of the pores.

10.In the compression test of soil, the soil sample in the compressor (consolidation instrument) is in the process of compression (b). [Chapter IV].

a.Only lateral deformation occurs.

b.Only vertical deformation occurs.

c.Both vertical and lateral deformation occur.

11.When the compressibility coefficient of soil A1-2 is in the range of (a), the soil is low compressibility soil. [Chapter IV].

a. a1-2<

mpa-1c. a1-2≥mpa-1

12.When the standard method is used to calculate the foundation settlement, the settlement empirical coefficient s is not related to (c). [Chapter IV].

a.The value of the pressure attached to the substrate.

b.Settlement calculates the equivalent value of the compressive modulus over the depth range.

c.The shape of the base surface.

13.The over-consolidation ratio (OCR) refers to (A). [Chapter IV].

a.The ratio of the early consolidation pressure of the soil to the self-weight stress of the existing soil layer.

b.The ratio of the self-weight stress of the existing soil layer to the pre-consolidation pressure of the soil.

c.The ratio of the self-weight stress of the existing soil layer to the later consolidation pressure of the soil.

<>1. Plane arbitrary force system, column three static equilibrium equations:

fx=0 (1)

fy=0 (2)

ma=0 is disturbed as closed -m+ (3).

2. In the plane parallel force rubber system, each research object can only list two independent static equilibrium equations, and the whole is selected: fy=0 nay+ (1).

ma=0 m+ (2)

Choose CB: fy=0 nb+ slow cracking (3)MB=0 -(3L 2)NC+ (4).

Solve the simultaneous equations yourself. The pointing of the arrow of the support reaction (moment) drawn in the figure is hypothetical, and if the result is negative, the actual direction of the support reaction force (moment) is opposite to the direction set in the figure.

The answer is: normal stress of a circular section and normal stress of a square section. The details are shown in the figure below.

Question 1 (Multiple Choice) The general force system of the plane is simplified to any point in the plane of action, and the incorrect one of the following options is ( ).

a. The general force system of the plane is simplified to any point in the plane of action to obtain a force and a force couple.

b. The principal vector is equal to the vector sum of the forces in the Force system.

c. The principal moment is equal to the algebraic sum of the moments of each force pair at the simplified center in the force system.

d. The principal moment is the resultant moment of the force system.

Question 2 (Multiple Choice) The properties of the two forces that do not belong to the composition of the force couple in the following options are ( ) a, equal in magnitude.

b. Opposite directions.

c. The lines of action are parallel and not collinear.

d. The lines of action are parallel and collinear.

Question 3 (Multiple Choice) If any force in a plane is simplified to any point in the action plane, and the main vector and principal moment are not zero, then the final result of the simplification is ().

a. A force couple.

b. A resultant force.

c. Balance. d. Not certain.

Question 4 (Multiple Choice) The following are the mechanical characteristics of the member shear deformation that do not belong to the ().

a. The forces acting on the members are equal in magnitude.

b. The forces acting on the members are in opposite directions.

c. The lines of action of the forces acting on the members are perpendicular to the axis and close to each other.

d. The forces acting on the members are not equal.

Question 5 (Multiple Choice) The internal force diagram of the beam is at the cross-section of the concentrated force couple, and the shear force diagram ( ) a, the shear force diagram has a sudden change, and the bending moment diagram is smooth and continuous.

b. There is a sudden change in the shear force diagram and a turning point in the bending moment diagram.

c. There is a sudden change in the bending moment diagram, and the shear force diagram is smooth and continuous.

d. There is a sudden change in the bending moment diagram and a turning point in the shear force diagram.

Dagong 12 spring "Engineering Mechanics (1)" full score answer.

1. Multiple choice questions.

1、a 2、c 3、b 4、a 5、d

1.If a point in the foundation is subjected to a large principal stress of 700kPa and a small principal stress of 200kpa, the shear stress acting on the surface at an angle of 30° to the small principal stress surface is ( ).

a.b. 280kpa

c. 320kpa

d.2.If the bottom width of a strip foundation is 1m, the buried depth is 1m, and the vertical load from the load-bearing wall is 150kN, then the base pressure p is ().

a. 150kpa

b. 160kpa

c. 170kpa

d. 165kpa

3.Which of the following is NOT a basic assumption of one-dimensional consolidation theory? ()

a.Soil particles and water are incompressible.

b.The soil layer is drained on one side.

c.The soil layer is homogeneous and saturated.

d.Pore water flow conforms to Darcy's law.

4.When using the elastic mechanics formula to calculate the final settlement of the foundation, the modulus in the formula should be taken ().

a.Modulus of deformation.

b.Compressive modulus.

c.Elastic modulus.

d.Modulus of resilience.

5.When the clay layer reaches 100% of the consolidation cavity sensitivity under the action of external load, the soil is ().

a.Only strongly bound water is present.

b.Only bound water is present.

c.Only bound water and capillary water are present.

d.There is free water.

6.Shear strength index of saturated cohesive soil ().

a.It has to do with drainage conditions.

b.It has to do with the width of the foundation.

c.Independent of the shear rate at the time of the test.

d.It has nothing to do with whether the pore water pressure in the soil changes.

7.If the bottom width of a strip foundation is 1m, the buried depth is 1m, and the vertical load from the load-bearing wall is 150kN, then the base pressure p is ( ).

a. 150kpa

b. 160kpa

c. 170kpa

d. 165kpa

8.The settlement completed by the general building during the construction period is usually different with the different soil quality of the foundation, and the gravel soil and sand soil are small in compressibility and permeability, and the amount of foundation settlement () during the construction period.

a.Completely or substantially completed.

b. 50％～80％

c. 20％～50％

d. 5％～20％

9.Two rectangular foundations are known, one 2m wide and 4m long, and the other 4m wide and 8m long. If the additional pressures of the two foundations are equal, the relationship between the vertical additional stresses at the corners of the two foundations ().

a.The distribution of the virtual force in the vertical direction should be the same at the Z depth under the combustion foundation of the two bases.

b.The stress at the z-depth at the corner of the small-sized foundation is equal to the stress at the 2z-depth under the corner of the large-size foundation.

c.The stress at the Z depth at the corner of the large foundation is equal to the stress at the 2z depth below the corner of the small foundation.

d.None of the above statements are correct.

10.When the consolidation degree of a clay foundation reaches 40%, the settlement amount is 100mm, and the final consolidation settlement is ().

a. 400mm

b. 250mm

c. 200mm

d. 140mm

1. Multiple choice questions.

1、d 2、b 3、d 4、d 5、d

1.Force is the interaction between objects and is responsible for the change in the state of motion of the object or the cause of the deformation of the object. The three elements of force do not include ().

a.Size.

b.Direction.

c.Point of effect.

d.Unit.

2.In the tensile test of mild steel, the stress fluctuates within a small range of the demolition width, and the strain increases sharply in the ( ) stage.

a.Elasticity.

b.Succumb.

c.Aggrandizement.

d.Neck contraction.

3.Among the following options that are not action and reaction forces are ( )aThe size is equal.

b.In the opposite direction.

c.Line of action is collinear.

d.Acting on the same object.

4.Using the equilibrium equation of the general force system of space, ( ) unknowns can be solved.

a. 2b. 3

c. 4d. 6

5.The bearing capacity of the components is mainly measured by the aspect of ( ).

a.Sufficient strength.

b.Sufficient stiffness.

c.Sufficient stability.

d.All three of the above.