Question 1

Two catalysts are being analysed to determine how they affect the mean yield of a chemical process. Specifically, catalyst 1 is currently used; but catalyst 2 is acceptable. Since catalyst 2 is cheaper, it should be adopted if it does not change the process yield. A test is run in the pilot plant and the results are shown as follows:

Catalyst Yield Data Observation Number 1 2 3 4 5 6 7 8 Catalyst 1 91.5 94.18 92.18 95.39 91.79 89.07 94.72 89.21
Catalyst 2 89.19 90.95 90.46 93.21 97.19 97.04 91.07 92.75

Is there any difference in the mean yields at 5% significance level assuming equal variances? [20]

Find the ultimate bearing capacity using Terzaghi for the given foundation located at 4.8m below ground. Water table at 2.2m below ground.

Soil A has H= 1.8m ɣ=15KN/m³, C=35 KN/m², ɸ= 25, and e= 0.42.

Soil B has H= 3.0m ɣ=16KN/m³, C=45 KN/m², ɸ= 35, and e= 0.49.

Before the foundation was laid compaction was done on both soils where results were

Soil A has ɣ_max=18KN/m³, optimum water content 11% and e=0.26.

Soil B has ɣ_max=20KN/m³, optimum water content 13% and e=0.29.

The foundation is 2.8x2.8m and its loosest void ratio for both soils are 0.90 and 0.82, respectively

1. A short reinforced concrete column is subjected to a 1000 kN axial compressive load. The moduli of elasticity of plain concrete and steel are 25 GPa and 207 GPa, respectively, and the cross-sectional area of steel is 2% of that of the reinforced concrete. Considering the column as a structural member made of a composite material and subjected to load parallel to the steel rebars, calculate the following:

a. the modulus of elasticity of the reinforced concrete

b. the load carried by each of the steel and plain concrete

c. the minimum required cross-sectional area of the column given that the allowable compressive stress of plain concrete is 20 MPa and that the allowable compressive stress of plain concrete will be reached before that of steel.

d. Plot the stress-strain behavior for the steel fiber, concrete and composite on the same plot.

A 1200 mm deep by 750 mm wide post-tensioned simply supported beam is shown below. The beam spans 12.0 m and is subject to a superimposed dead load of 50 kN/m and a live load of 35 kN/m. Both the superimposed dead load and live load are applied after transfer (after stressing has taken place). The tendon is located at the mid-height of the beam at each end, and its centreline sits 50 mm from the base at midspan. The concrete strength at transfer is 22 MPa, and at maturity is 40 MPa. Assume Ec = 32800 MPa, γc = 24 kN/m3 and ignore any prestress losses. You are to assess the following:

a) If Pi = 2700 kN, assess the adequacy of the beam at transfer. In addition, assuming Pi cannot be changed, briefly describe three methods that could be used to ensure the transfer stresses are within code limits.

b) If Pi = 1750 kN and all the load has been applied, determine the percentage of the total dead load balanced.

c) Estimate the approximate total short-term and long-term deflection under the load combination G + 0.7Q. Assume Pi = 1750 kN and Фcc = 2.8.

d) If the beam has the reinforcement arrangement shown below, assess the ultimate moment capacity under the load combination 1.2G + 1.5Q. Assume fpy = 1780 MPa, fpb = 1920 MPa and fsy = 500 MPa. Note: Ast = 2464 mm2, Asc = 1808 mm2 and Ap = 1790 mm2. Only two iterations of dn are required.

reveals a longitudinal section of a circular tube with a length of l = 300 m. Additionally, the absolute roughness of the boundary, the diameter of the circular tube, the continuous loss over the whole length and the kinematic viscosity of the real fluid are given. Longitudinal section of a steel tube Given l = 300 m k = 1 mm d = 1.00 m hLoss, continuous = 0.50 m ν = 1.3 * 10-6 m2 /s For a similar system the continuous loss coefficient λ was derived to λ = 0.02. i)

Prove, if this λ – value can be applied here to calculate the discharge in the circular tube by clearly showing your way (intermediate steps) of proof using the Moodydiagram.

ii) Calculate the discharge Q running through the circular pipe.

What is the importance of calculating the effective stress in a soil mass?

What are the practical applications of numerical methods. Give all and explain briefly each.

Sainte-Chapelle In Paris

1. How is the structure supported and is that structure visible to the viewer inside?

2. When built it held what two records?

3. What does the Sainte-Chapelle chapel resemble?

4. Define: Hemicycle

please no handwriting

Give the steps in solving the Residue and Relaxation method.

1.Melting point of TiO₂ is 1843^oC. A TiO₂ pellet was sintered at 627^oC for 1 hour. The resulting pellet will have the following characteristics.

No sintering activity and remains as a powder is the correct answer among the choices. I would just like an explanation to why.