TABLE OF CONTENTS

No. Description Page No.

1.0 INTRODUCTION………………………………………………………….3

1.1 Scope………………………………………………………………………3

1.2 Standard and Document………………………………………………....3

2.0 PAVEMENT DESIGN ……………………………………………………3

2.1 General…………………………………………………………………….3

2.2 Parameters for Pavement Design………………………………………3

2.2.1 Design Life….……………………………………………………………..3

2.2.2 Traffic Loading…………………………………………………………….3-4

2.2.3 Subgrade Class..…………………………………………………………4

2.3 Pavement Design By QHDM…………….……………………………..4

1.0 INTRODUCTION

The design and calculation of flexible pavement involved in access,internal and side road for the proposed QSTec POLYSILICON Project, Phase-I at Qatar.

1.1 Scope

Design calculation for flexible pavement of access, internal and side road of the above mentioned project.

1.2 Standard and Document

The following standards and documents have been followed for preparation of this document Qatar Highway Design Manual (QHDM) Qatar Construction Specification 2007 (QCS 2007) Specification for Road (Doc. No. PS1053-G0000-11-SSP-A4-0001 Geotechnical Survey Report (Doc. No. PS1053-G0000-01-REP-A4-

0001)

2.0 PAVEMENT DESIGN

2.1 General

Pavement design basically aims at determining the total thickness of the pavement structure as also the thickness of the individual layers required for good performance and for effectively standing against the expected traffic loading and prevailing environmental conditions over the design period.

For flexible pavement design, the procedure given in the Qatar Highway Design Manual is adopted.

2.2 Parameters for Pavement Design

2.2.1 Design Life

Pavement (Flexible) is designed for a design life of 20 years.

2.2.2 Traffic loading

Axle Load

For design traffic loading calculation, axle load is considered as 13 ton.

Standard Axles

The standard axles against 13 ton axle loading is adopted as 6.45

Cumulative Equivalent Standard Axle Load

Design traffic loading is calculated to 1.88 million equivalent standard axle after calculation for a design period of 20 years. So the design traffic is under traffic class T2 (1-2 MSA).

2.2.3 Sub grade Class

Soil samples at different test pit locations of the project area were tested, and the minimum soaked CBR found 18.9 percent. So the design subgrade class is adopted as S1(CBR greater than 15% and less than 25%).

2.3 Pavement Design By QHDM

The pavement composition with asphalt concrete road base against traffic class T2 and subgrade class S1,can be adopted from figure 9.2 of QHDM as below :

Wearing Course (Asphalt Concrete MD4) : 40 mm

Roadbase (Asphalt Concrete MD1) : 130 mm

Sub-base (Granular Material) : 200 mm

Subgrade (CBR at 95% of MDD) : 300 mm