Basic Structural Eng G

 

MEGAREVIEW & TUTORIAL CENTER

 

Find the resultant of the three forces acting on the eye bolt.

 

Evaluate the resultant of the force system shown.

 

Determine the compression in each of the three legs of the tripod subjected to the vertical 2-kN force. The weight of the legs is negligible compared with the applied load.

 

Determine the bar forces if in addition to 2 kN lo load ad an an adde added d concentrated load of 5 kN dir direc ecte ted d to th the e positive x axis is added.

 

Determine the tension in cable AB Determine the tension in cable AC. Determine the tension in cable AD.

 

Four cables are used to lift a precast concrete slab with dimensions B = 3m x D = 3m and t = 76mm thick . The cables are attached to a hook above the center point of the slab. Given: h = 2m Area of each cable = 79 mm2 kN/m3

Concrete

unit

weight

=

24

What is the tensile force in each of the cables? Determine the normal stress in each of the cables. If the cables elongated by 1mm, what is the vertical displacement of the prec pr ecas astt sl slab ab??

 

Refer to the figure. A square post 150 mm x 150 mm is made up of two parts glued along plane a-b-c-d. a -b-c-d. The plane is at an angle, α = 30 from the vertical side. °

Given:

Allowable stresses on the glued joint Compressive Stress = 5.2 MPa Shear Stress = 3.5 MPa Compressive Load = 36 kN

What is the required minimum width of the post, w (mm), to prevent failure in the compression? Which of the following gives the minimum width, w (mm), to prevent failure in shear?

 

a nd has an A steel rod having a length of 2.5 m and axial rigidity 60,000KN. It is subjected to an axial tensile force of 60KN. Determine the deformation of the rod. Determine the stiffness of the rod. Determine the flexibility of the rod.

 

A steel bar of cross-section 500mm² is acted upon by the forces shown in the figure. Determine the total elongation of the bar.

 

Shaft BC is hollow with inner and outer diameters of 90 mm and 120 mm, respectively. Shafts AB and CD are solid and of diameter d. For the loading shown, determine: The maximum and minimum shearing stress in shaft BC, The required diameter d of shafts AB and CD if the allowable shearing stress in these shafts is 65 MPa.

 

The horizontal shaft AD is attached to a fixed base at D and is subjected to the torques shown. A 44-mmdiameter hole has been drilled into portion CD of the shaft. Knowing that the entire shaft is made of steel for which G = 77 GPa, determine twist at endthe A. angle of

 

A spread footing carries two (2) column loads as shown. Given: P1 = 1200 kN b = 10 m P2 = 800 kN c=2m Find the resulting minimumsoil dimension in meters such that the pressure‘a’ shall be uniform.

Given:

P1 = 1200 kN P2 = 1200 kN

a=3m b=6m c=3m What is the maximum shear (kN) at the footing? Assume 1 m width of footing. Given:

P1 = 1200 kN P2 = 1200 kN

a=3m b=6m

c =from 3 mthe left Locate the point of inflection lef t end of the footing, in meters.

 

Given a rectangular hollow box with outer dimensions 125mm x 85mm and constant thickness of 10mm has an ultimate stress of 415 MPa. Modulus of Elasticity of 110 GP GPa. a. Determine the bending moment M for which the factor of safety will be 2.50. Determine the corresponding radius of curvature of the section.

 

A thin wall spherical tank of diameter 0.75 m has internal pressure of 20 MPa. The yield stress in tension is 920 MPa, and the factor of safety is 2.5. Calculate the minimum permissible thickness of the tank.

 

A cylindrical tank is filled fil led with water to a depth of 2.8m in its vertical position. The tank dimensions are as follows: Given: He Height = 3m Thickness = 8mm

Diameter = 2.5m Weight = 14.5kN

What is the maximum circumferential stress (MPa) in the tank? The tank is supported suppor ted only at the top. What is the maximum longitudinal stress (MPa) in the tank? The tank is supported suppor ted at the top and at the base. Determine the maximum longitudinal stress (MPa). (MPa).

 

A simply supported girder of a bridge spans 25 m. The standard truck load (H load) consists of 2 moving loads, m apart. P =4.3 35.6 kN The loads are as follows: 1

P2 = 142.4 kN Calculate the maximum support reaction (kN). Calculate the maximum moment (kN-m) in the girder. Calculate the maximum shear (kN) at midspan

 

A 12-meter-long beam is simply support rte ed at the right end and at 2 meters from the left end. It is subjected to a highway load consisting of 9.35 kN/m uniformly distributed load and 116 kN cmo onm ceen nttraat tem d id lo aan, d. , Based on the influence line for maximum mom ent idsp span What is the total length in meters of the beam which should be subjected to a uniformly distributed load to obtain the maximum posi po siti tive ve mom omen entt at mid idsp spa an? What is the total length in meters of the beam which should be subjected to the uniformly distributed load to obtain the maximum nega ne gati tive ve mom omen entt at th the e mid idsp span an?? What would be the critical positive moment (kN-m) at midspan due to the highway lane load?

 

The side of the building in the figure is subjected to a wind loading that creates a uniform normal pressure of 15kPa on the windward side and a suction pressure of 5 kPa on the leeward side. Determine the horizontal reaction at A. Determine the vertical reaction at A. Determine the horizontal reaction at B. Determine the vertical reaction at B. Determine the horizontal reaction at C. Determine the vertical reaction at C.

 

For the three-hinged arch shown in the figure: Determine the horizontal reaction at A. Determine the horizontal reaction at C. Determine the vertical reaction at C.

 

The truss shown in on a roller support at A and hinged at B. It is subjected to a lateral load F = 12 kN. Given: a = 1.5 m b=4m c = 3.5 m Determine the reaction at A, in kN. Determine the force in member AE, in kN. Determine the reaction at D, in kN.

 

A transmission tower is loaded as shown. P1 = 10 kN P2 = 13 kN P3 = 16 kN Determine the total reaction at H, in kN. Determine the force in member CJ.

 

Refer to the figure FIG. THEORY-010. Diagonals BH, CG, HD, and CI are flexible cables. Given: P1 = 2.5 kN P2 = 0.0 kN P3 = 1.2 kN L1 = 3m L2 = 2.25m L3 = 3m

 

Determine the force on member CG. Determine the force on member DH. Determine the force on member DI.

 

The water supply pipe shown is suspended from a 100 mmØ cable using using a series series of of equally space spaced d hangers. hangers. The length of the pipe that is supported by the cable is 50 meters and the total weight of the pipe filled with water is 8 kN/m. If the sag of the cable at mid length is 2.5 m.

 

Evaluate the minimum axial stress in the parabolic cable, in MPa. Determine the reaction at one of the supports Find the maximum axial stress in the parabolic cable, in MP MPa. a.

 

suppor ts a girder that weighs 850 The cable in the figure supports lb/ft. Determine the tension at C. Determine the minimum tension in the cable. Determine the maximum tension in the cable.

 

An 8-m high retaining wall is subjected to lateral earth pressure increasing from 34 kPa at the top to 136 kPa at the base. Flexural rigidity EI = 4.5x1014 Nmm2. Analyze per meter length of the wall. What is the moment at the base of the cantilever retaining wall, in kNm? What is the force to be applied at the propped end to limit the deflection to 35 mm, in kN? What is the moment at the base when the wall is propped at the top?

 

supp orted by a roller at the right end and a fixed A 6m long beam is supported support at the left lef t end. It carries a uniform load of ‘w’ kN/m throughout the beam. Compute the safe value of ‘w’ so that it will not exceed the flexural capacity of the beam of 270 kN-m, in kN/m. Compute the safe value of ‘w’ so that it will not exceed the shear capacity of the beam of 180 kN, in kN/m. Compute the safe value of ‘w’ so that it will not exceed the deflection of 30 mm at the right end when the roller support suppor t is removed.

Flexural rigidity of the beam is 432x1012 Nmm2 in kN/m.

 

A cantilever beam 4 m long deflects by 16 mm at its free end due to a uniformly distributed load of 25 kN/m throughout its length. To prevent beam deflection at the free end, what force P (kN) ( kN) is needed at that point? What force P (kN) should be applied at the mid length of the beam for zero displacement at the free end? To reduce the deflection at the free end to 10 mm, how much force is needed to be applied at that point?

 

unifor mly A cantilever beam 2 meters long carries a uniformly distributed load of of 18 kN/m throughout its length and a concentrated load load of 25 kN at mid-length. To To minimize the displacement, a spring support is added at the free-end. Given: Spring consta constant nt K = 0.10 mm for every every 1 kN of compr compressive essive load Flexural rigidity, EI = 2500 kNm² 1. Calculate the reaction (kN) at the spring support. 2. spring support by 0.50 mm, mm, what is the If the resulting reaction is incompressed kN? 3. If the reaction at the spring support is 25 kN, what is the resulting moment (kN-m) at the fixed end?

 

Give Given: n: a = 1.5 m,

b = 1.5 m,

Beam properties: Rod proper ties:

I = 198 x 106 mm4 Diameter = 12 mm

L = 2.4 m E = 200 GPa E = 200 GPa

 

Due to the load, W, rod BC elongates by 1 mm. Find the force (kN) in rod BC which caused the elongation. Due to the load, W, the force developed in rod BC is 12 kN, what is the value of W (kN)? Due to a load, load, W = 40 kN, the force developed in rod BC = 10 kN. The diameter of rod BC is 16 mm. Find the moment (kN-m) at the fixed end.

 

Treated timber piles used to retain earth ear th are braced by struts at B and anchored to bedrock at 1 m on center spacing. Water pressure acts against the lateral earth pressure. Given:

H1 = 3m H2 = 2m 3 H3 = 3m Unit weight of soil = 17.3 kN/m Unit Weight of water = 9.8 kN/m3 Flexural Rigidity, Rigidity, EI = 8.72 x 10^12 Nmm2 Active Earth pressure coefficient = 1/3 Assume that the piles are fixed at C. If there are no anchor rods, how much is the deflection (mm) at the tip? If H3 = 0 (no water pressure), what should the force (kN) in the anchor rod so that there is no deflection at the tip of the pile? If the allowable displacement at the tip of the pile is 12 mm, and there is no water pressure, Find the force (kN) required at the anchor rod.

 

Wood planks are used to retain 3 m height of backfill. The active earth pressure increases from zero at the free end to 14.5 kPa at the fixed end. Give Gi ven: n: Plan Pl di ions ns Thank ickkndime esmens s nsio = 100 mm Width = 300 mm Modu Mo dulu luss of of Ela Elast stic icit ityy = 8.5 8.5 x 103 103 MP MPa a Which of the following gives the lateral reaction (kN) at the fixed end if the planks are propped at the free end. If the wood planks are supported by a strut at mid-height, what pulling force (kN) should be applied at the strut to prevent the free end from deflecting? Which of the following gives the maximum bending stress (MPa) in the cantilevered wood planks?