Study Guides (248,283)
Canada (121,453)
CIVE 202 (4)
Midterm

CIVE 202 Midterm: Quizzes Pre_Midterm

5 Pages
75 Views
Unlock Document

Department
Civil Engineering
Course
CIVE 202
Professor
Andrew Boyd
Semester
Winter

Description
The following is a compilation of the Tutorial questions for the material covered before the midterm: Mechanical Properties of Materials 1. What is the difference between stress and force. 2. What is the difference between deformation and strain? 3. Stress-Strain Curves a. Name each point or region (1 to 6) on the following stress-strain curve. b. Explain the difference between Curve A and Curve B. 4. What happens to the ductility of steel in the following conditions: a. Increasing the rate of applied strain b. Increase the material temperature Solutions: 1. What is the difference between stress and force 𝑷 Stress= Force/Area, 𝛔 = , 𝑨 2. What is the difference between deformation and strain? Deformation= Physical length change (length measurement) = 𝚫𝑳 𝚫𝑳 Strain = dimensionless proportion of deformation to original length 𝝐 = 𝑳 3. a. Name each point or region (1 to 6) on the following stress-strain curve 1. Yield Stress 2. Ultimate Engineering Stress 3. Rupture/failure stress 4. Elastic region, Modulus of Elasticity, Modulus of resilience 5. Strain Hardening region 6. Necking b) Curve A is traditional/engineering curve, assuming constant cross sectional area Curve B is a true curve which takes into account the increased stresses due to a smaller cross sectional area which is caused by localized necking (Ductile material) 4. What happens to the ductility of steel in the following conditions: a. Increasing the rate of applied strain Higher Strain rate: Less Ductile, more Brittle b. Increase the material temperature Higher temperature More Ductile, less Brittle Concrete mixing 1) Define and briefly explain the 5 primary steps of concrete production and use. (2.5pts) 2) Explain the importance of controlling the water content in fresh concrete. (2pts) 3) Define segregation and bleeding and how they are related to workability. (3pts) Solution: 1) Define and briefly explain the 5 primary steps of concrete production and use. (2.5pts)  Batching: weighing out ingredients (cement, aggregates, water, admixtures)  Mixing: using different techniques, speed and temperature.  Transporting and Placing  Finishing: compaction (by vibrating), troweling, texturing.  Curing: Prevents loss of moisture and provides additional moisture. 2) Explain the importance of controlling the water content in fresh concrete. (2pts) W/C should be 0.42 theoretically for hydration to be total, however loss of moisture due to aggregates absorption and evaporation. Need to control the environment and take absorption into account in order to have optimal conditions for the fresh concrete, affects durability. 3) Define segregation and bleeding and how they are related to workability. (3pts) a. Segregation: separation of components of fresh concrete, resulting in non- uniform matrix. Caused by: large maximum aggregate size & proportion of large particles, high specific gravity of coarse aggregates relative to fine, decreased amount of fine aggregates, variation of particle shape and smoothness, mixes that are too wet or too dry. Segregation can be reduced by the use of SCMs and AEAs, but careful handling and placement is more important. b. Bleeding: upward movement of water after concrete has been consolidated, but before it sets. Caused by the aggregates setting within the fresh concrete and being unable to hold all the mixing water. Causes increased permeability of the hardened concrete  reduced durability and weakness., reduced bonding. Cement, SCM and Admixtures 1. Name 3 cement components. 2. What is the difference between pozzolanic and cementitious SCM’s in terms of their hydration reactions? 3. How do air entraining ad-mixtures work, and what durability issues are particularly mitigated by its use? 4. How does Superplasticizer work? Name a couple of applications where concrete with superplasticizer might be desirable. Solutions: 1) 3 of the following: C3S C2S C3A C 4F CSH 2 2) Pozzolanic react
More Less

Related notes for CIVE 202

Log In


OR

Join OneClass

Access over 10 million pages of study
documents for 1.3 million courses.

Sign up

Join to view


OR

By registering, I agree to the Terms and Privacy Policies
Already have an account?
Just a few more details

So we can recommend you notes for your school.

Reset Password

Please enter below the email address you registered with and we will send you a link to reset your password.

Add your courses

Get notes from the top students in your class.


Submit