LABOUR-BASED METHODS AND TECHNOLOGIES for …

BEST PRACTICE GUIDE

LABOUR-BASED METHODS AND

TECHNOLOGIES

for

EMPLOYMENT INTENSIVE

CONSTRUCTION WORKS

January 2002

TABLE OF CONTENTS

Glossary of terms

Preface

Part 1 An overview of labour-based technologies and methods in infrastructure projects

Part 2 Labour-based construction methods

1.

Labour-Based Construction Methods for Earthworks

Note:

This section focuses on earthworks and provides practical information on the classification of earthworks

for hand excavation, field tests to confirm densities achieved and the construction of unsurfaced roads. It

also include guidance on compaction by means of hand stampers in service trenches.

Part 3 Labour-based methods for materials manufacture

1.

Precast Concrete Products, Bricks and Block Making

Other sections to be included when developed

Part 4 Labour-based construction technologies

1.

2.

3.

4.

5.

6.

7.

8.

Labour-based open channel flow technology

Rubble masonry concrete dam construction technology

Rubble masonry concrete arch bridge construction technology

Foamed bitumen gravel.

Cast in-situ Block Pavement (Hyson Cells)

Emulsion treated gravel

Waterbound Macadam

Slurrybound and Composite Macadam Construction

Other sections to be included when developed

Note:

The format of each sub-section in this part is generally as flows:

1)

Introduction

The technology is briefly described and discussed as well as any philosophy behind the technology /

performance and behaviour of the technology. A brief history of its application within South Africa and beyond

the borders of South Africa is also be presented.

2)

Materials requirements

The material requirements are described and a model specifications are presented

3)

Plant and equipment requirements

The plant and equipment requirements are described.

4)

Design considerations

This section sub-covers aspects such as factors that influence the design, appropriate design methods and

techniques, and the design process.

5)

Construction technique

This sub-section addresses specific design processes, procedures, specifications and potential pitfalls. It also

addresses aspects of quality control and acceptance criteria

6)

Specialist and related literature

This sub-section provides information on specialist literature relating to design and construction techniques.

GLOSSARY OF TERMS

Construction Works means the provision of a combination of goods and services arranged for the

development, extension, installation, repair, maintenance, renewal, removal, renovation, alteration,

dismantling or demolition of a fixed asset including building and engineering infrastructure.

Labour- based in relation to the production process and technologies used in the production of goods

and materials and in Construction Works means methods of production and technologies that are

designed and managed so as to promote the creation of employment with predetermined socioeconomic benefits.

Employment-intensive is a generic expression that is used to describe strategies, programmes,

projects, activities and assets which will promote direct, short-term or long-term employment

generation at the highest possible level;

Expenditure per unit of employment generated is the ratio of the total construction cost, including

any management fees directly related to construction activities, to the total employment opportunities

that are generated in the construction of a structure or service.

Procurement is the process that creates, manages and fulfills contracts.

Note:

Procurement as such is concerned with activities that both precede and follow the signing of a contract.

Targeted Procurement is a system of Procurement which is used to create a demand for the

services and supplies from, or to secure the participation of, targeted enterprises and targeted labour

in contracts in response to the objectives of a preferential procurement policy.

PREFACE

Background

The White Paper on Creating an Enabling Environment for Reconstruction, Growth and Development

in the Construction Industry (2000) expresses, inter alia, a vision for public-sector delivery which aims

to maximise employment opportunities through labour-intensive construction. In this regard, it calls for

an enabling regional policy that advocates the use of locally based technologies and encourages

labour-based construction and materials production. The Construction Industry Development Board

Act (Act 38 of 2000) states that the objectives of the Board are to, inter alia, determine and establish

best practice that promotes national social and economic objectives, including labour absorption in

the construction industry.

The Green Paper on Public Sector Procurement Reform in South Africa (1997) proposed that

Procurement should facilitate the generation of jobs in South Africa by:

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ensuring that the foreign content in contracts involving goods, services and works is minimised.

encouraging the substitution of labour for capital.

supporting the use of ¡°labour friendly¡± technologies which utilise a higher degree of labour input

than is the case for conventional technologies, or are well suited to implementation by small scale

enterprises.

encouraging and developing small scale enterprises to implement employment intensive practices

and ¡°labour-friendly¡± technologies.

All of the above presupposes that appropriate labour-based methods and technologies are readily

available to those engaged in construction works as designers and constructors.

The impact of choices in technology and construction methods

Engineers have traditionally used their skills and expertise to ensure that structures or structural

components are serviceable and durable in addition to possessing adequate strength and stability.

However, there is now a need for this traditional role to be broadened and expanded if engineers are

to contribute towards meeting current socio-economic needs. Definite relationships exist between

employment opportunities, available skills, entrepreneurship and the use of small scale enterprises in

the creation and maintenance of assets. The construction strategies that are adopted can be used to

address social and economic needs and concerns and, depending upon how they are structured, to

facilitate the economic empowerment of marginalised sectors of society in a focussed manner. Thus,

the process of constructing assets can be just as important as the provision of the assets themselves.

Choices in technologies and construction and manufacturing methods determine:

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the number of employment opportunities generated for a particular activity / process;

where employment opportunities are located; and what kind of enterprises can execute

contracts.

Research in South Africa has indicated that provided there is little or no cost premium associated with

employment intensive practices, the overall increase in employment opportunities for a given

infrastructure project over conventional plant-based practices may reach a factor of 2 in urban

infrastructure and 3 in rural road construction; increases which are extremely valuable.

The availability, or lack thereof, of appropriate specifications and suitable technology choices can

have a marked influence on the degree to which socio-economic objectives can be attained on works

contracts. Appropriate specifications and labour based technologies are required to optimise the

engagement of smaller contractors and the increase in employment opportunities per unit of

expenditure. The absence of design information on labour based technologies frequently leads to the

situation in which only those technologies for which there is adequate design information are

considered in the design of a project. Alternatively, labour based technologies are approached

circumspectly and conservatively

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The use of procurement to promote labour-based objectives

Targeted Procurement when used to promote social objectives associated with employment creation

cannot be divorced from choices in technology. Choices in technologies are frequently required to

increase demand, particularly where increases in employment per unit of expenditure and the use of

local resources are targeted. Targeted Procurement and the choice of technology are as such the

engines for growth in employment.

Markets are driven by supply and demand. Targeted Procurement creates the demand for Targeted

Labour and the demand for services and products of Targeted Enterprises.

Targeted

Procurement accordingly provides access to markets for both Targeted Enterprises and Targeted

Labour. Supply side interventions are, however, required to ensure that the demand is balanced by

the supply. Targeted Procurement creates the demand for targeted labour and targeted enterprises.

The success or otherwise of the use of Targeted Procurement in job creation programmes is

frequently dependent upon technical choices being made available to bidders. Appropriate

specifications are accordingly required to optimise the engagement of smaller contractors and to

increase the employment opportunities generated per unit of expenditure.

The challenge to engineers

The challenge to engineers is, in the first instance, to understand the potential which construction

projects have for delivering socio-economic deliverables, and thereafter to use their skill, knowledge

and creativity to realise these deliverables. This is often easier said than done, particularly where

unconventional or innovative technologies are required to be implemented on a large scale,

particularly in view of:

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the lack of availability of technical information to enable informed design decisions to be made;

the lack of suitable on-site acceptance tests

the reluctance of authorities to accept structures whose strength, stability, serviceability and

durability cannot be quantified and assessed in terms of national or international codes of

practice;

the reluctance of clients to pay for research and development.

Clearly, the individual engineer does not have the necessary resources to overcome the foregoing

difficulties. Furthermore, the engineer, who must assume responsibility for the safety/adequacy of the

structure, is, naturally, reluctant to place himself at risk by deviating from accepted norms. In the

absence of authoritative documentation and codes of practice, the contribution that an engineer can

make to the attainment of socio-economic deliverables is, accordingly, often limited.

The aim of the best practice guide

This best practice guide presents current best practices in a wide range of labour based construction

methods, manufacturing methods and technologies that have been successfully utilised in South

Africa in recent years. The guide is intended to provide sufficient technical information on such

methods and technologies to enable those responsible for the design of projects to make confidant

and informed choices on their use in projects, constructors to embrace such techniques and clients to

accept such technologies with confidence.

This publication is by no means exhaustive; hence the loose leaf format. Contributors wishing to make

submissions for the inclusion of further material or to update existing material in the light of their

recent experiences are invited to do so. Submissions should be made to:

The Director: Construction Industry Technology Enhancement

Department of Public Works

Private Bag X65

Pretoria, 001

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