Module Code: CN3331
Page 1 of 6
UNIVERSITY OF WOLVERHAMPTON
SCHOOL OF ENGINEERING AND THE BUILT ENVIRONMENT
BUILT ENVIRONMENT DIVISION
Module: Construction Technology 4
24 May 2004
Date of Examination:
9:30 – 12:30
Time of Examination:
Answer 4 questions in total
Number of Questions to be attempted: Section A - Compulsory
Section B - Answer any 3 questions
CONSTRUCTION TECHNOLOGY 4
Your client is a firm of private developers specialising in commercial projects. They have
recently taken an option to purchase a site in Shropshire comprising:
A redundant Royal Air Force (RAF) residence buildings, together with the freehold of
approximately 21 acre of redevelopment land to the rear which is presently used for
parking aircraft. The rear of the site is also occupied by several single storey
prefabricated buildings (used as aircraft hangers / storage / repairs etc) each building
having a gross external floor area of 5000 Sq. Metres.
The residential and prefabricated buildings were designed in 1930’s under the direction of
the Air Ministry as part of the re-armament programme.
The site is located in Cosford, a valley surrounded by hills having steep slopes on all
sides of the site. The site enjoys scenic views’ (looking onto the country side and the
Shropshire hills), which attracts tourists. The site fronts onto the main high street, which
accommodates a mix of uses such as residences, shops, offices and commercial buildings
The Residential Building
The basic structure of the residential building comprises reinforced concrete columns
with concrete flat roof construction and concrete blockwork with render finish. The flat
roof is covered with asphalt surrounded by reinforced concrete parapet wall built off the
concrete roof slab. The floors are insitu concrete and galvanised steel framed side-hung
casement windows are incorporated into the cladding panels to provide natural light and
ventilation to the interior.
The Prefabricated Building
The prefabricated building at the rear comprises a steel structural frame with part
brickwork (up to 1.5M) and concrete shell walls overlaid with asbestos sheeting. The
building(s) are enclosed with a barrel roof made up with concrete shell construction with
asbestos sheeting painted with bitumen.
State and Condition
The residential building has major defects of the structural frame such as:
i. cracking of the exposed areas of the concrete
ii. rusting of the reinforcements.
iii. dampness on the walls and floors.
iv. severe cracking of the render finish.
v. mould growth; pattern staining and efflorescence on the walls
Detailed laboratory testing has indicated that these defects are mainly related to chemical
attack associated with carbonisation, sulphate attack, calcium silicate reaction, high
alumina cement and chloride attack. The building also has presence of asbestos (blue
and white asbestos) based material located around service pipe work and ducts.
The prefabricated building has a history of structural movements and consequently it has
been vacant for the last 20 years. Structural movement associated with insufficient
bearing capacity of the ground, adverse point loads internally resulting in cracking of the
floor slab and movement of the portal frame and deterioration of asbestos panels due to
poor patch repairs in the past together with general ageing. This exhibiting the following
i. Rainwater penetrates through the vertical / horizontal joints of the asbestos; resulting
in diagonal cracking to the inner skin and rusting of the frame structural.
ii. The external cladding is exhibiting evidence of weathering as evidenced by the
asbestos sheeting becoming delaminated with breakdown of fibres progressively
being exposed together with visible rusting.
iii. Floor slab fractured allowing damp patches to appear (which frequently appear /
disappear). External brickwork exhibits evidence of rising damp.
iv. The structure has in places sunk into the ground approximately 1M,
Preliminary planning enquiries indicate that so far as the residential building is concerned
planning consent would be forthcoming:
a. demolition of the existing structure and replacement with new structure having
same footprint, with car parking provision being accommodated in the basement
b. retain the existing building, undertake substantial structural repairs to bring the
property fit for human habitation by redesigning the internal layout and providing
self contained luxury apartments.
In the case of the single storey prefabricated block the planning authority has indicated
that no objection would be raised to its demolition and replacement by out of town a one-
stop shopping centre having a low-rise long span structure.
Your Client has expressed concerns regarding the speed of construction, demolition;
health and safety aspect in design, construction and management; aesthetics, position of
the proposed works adjacent to existing buildings, energy efficiency and maintenance
The situation of the buildings together with the adjacent land are shown on the attached
location plan. Internal layouts are shown on the floor plans also provided. The drawings
(2No. in total) provided are incomplete but give indicative details of the property.
SECTION A - Compulsory Question
1. Your Client has retained your company as Project Managers (offering a full
range of services ranging from Professional Design services together with
Health and Safety).
As a Principal Contractor prepare a health and safety plan to accompany the
tender documentation for the demolition and or refurbishment of the existing
iii In particular, your clients are concerned that they discharge their statutory
obligations under the CDM regulations, in addition to the health and safety
plan. Explain the workings of the CDM regulations and how these affect them
as developers throughout the entire contract (ie demolition, new build and
SECTION B - Answer any 3 questions
2. i. Describe and evaluate in detail the principal causes of the chemical reaction and
the symptoms of any two the following defects in concrete structures:
ii. Sulphate attack
iii. Chloride attack. 2 x 5%
v. High Alumina Cement.
ii. Write a specification to remedy any of the above two defects in concrete
structures 2 x 5%
3. a If the existing residential buildings were being retained, explain to your client 15%
how the existing building could be up-graded to ensure that the building is fit for
b Your client is keen on green issues and wishes the energy efficiency of the
retained buildings to be up graded to a standard approaching that of new build
Using annotated and detailed sketches to support your response, advise your 5%
clients how this might be achieved.
4. i. Advise your client on the implications of the presence of asbestos upon the users
and occupiers of the buildings. 10%
ii The importance of any precautionary measures that need to be implemented if:
a. Asbestos was to be retained 5%
b. Asbestos was to be removed 5%
5. Your client is considering the introduction of a planned maintenance system for
the project as a whole.
Using examples where appropriate, provide a detailed commentary and
description of the application of the decision-making procedure for setting up a
maintenance programme. 20%