ENGINEERING

Civil Engineering [Name of the Writer]

[Name of the Institution]

Civil Engineering

Task A. Civil Engineering Measurement

(i) Retaining wall excavation

Retaining wall design can be a tedious simple task to carry out. A retaining wall design has to account for a number of factors, foremost being the stability of the wall itself. Last, the design has to account for the specific retaining wall type that is used (Kelly, 1992, 49). In simple terms, different retaining wall types might require some additional design checks. Typically, a retaining wall design has to consider the following:

Subject to General University Examinations Regulations, there are other specific regulations pertaining to this programme, details of which can be sought from the office of the College Academic Registrar.

The following additional letters shall be used, where appropriate:

W - Withdrawal from Course

I - Incomplete

AUD - Audited Course only

The Course Pass Grade Point is 2.0

No Credit Unit shall be awarded for any Course in which a student fails.

The diploma awarded to the successful candidate shall be designated as Dip.

The diploma shall be classified according to the CGPA as follows:-

CLASS

Distinction

CGPA

4.40 - 5.0 3.60 - 4.39 2.80 - 3.59 2.0 - 2.79

Credit, Upper Division Credit Lower Division Pass Pass

The cumulative grade point average at a given time shall be obtained by:-

i)Multiplying the grade point obtained in each course by the credit units assigned to the course to arrive at the weighted score for the course.

ii)Adding together the weighted scores for all courses taken up to that time.

iii)Dividing the total weighted score by the total number of credit units taken up to that time.

The Diploma in Civil Engineering Surveying shall be awarded to a Candidate who obtains a minimum of 79 credit units, gained from 27 Course Units all of which are core courses as indicated in Table 2.

Table 2: Requirements for Graduation

YearCoreElectives

one14014 Core Courses; No Electives

Two13013 Core Courses; No Electives

Total Courses 27041 Core Courses; No Electives

a) Earth - Water pressures in retaining wall design

Before all, a designer has to appropriately select the type of lateral earth pressures that are expected to act on the wall. For most retaining walls active or at-rest, earth pressures are appropriate. Passive soil resistance should be used with caution. The possibility of including water pressures has to be considered if sufficient drainage is not provided (Kelly, 1992, 49). In the UK, depending on the design approach, some design codes (LRFD) apply safety factors that multiply each pressure by a safety factor. In Europe, a strength design approach is applied where soil strength is divided by safety factors and loads are multiplied according to their nature (temporary and permanent).

b) External Stability checks in retaining wall design

External stability checks refer to calculations that represent the overall stability of the retaining wall as if the retaining wall structure acts as a single body (Kelly, 1992, 49). Two calculations are typically performed:

b1) Sliding stability of retaining walls:

This calculation considers the retaining wall stability in the horizontal direction. The horizontal components of forces are calculated and separated into driving and resisting ...