Pavement Manual

Draft May 2016

Texas Department of Transportation

Table of Contents

Chapter 1, Introduction

Chapter 2, Pavement Design Process

Chapter 3, Materials Investigation and Selection Information

Chapter 4, Pavement Evaluation

Chapter 5, Flexible Pavement Design

Chapter 6, Flexible Pavement Construction

Chapter 7, Flexible Pavement Rehabilitation

Chapter 8, Rigid Pavement Design

Chapter 9, Rigid Pavement Construction

Chapter 10, Rigid Pavement Rehabilitation

Chapter 11, Ride Quality

Chapter 12, Premature Distress Investigations

Chapter 13, Load Zoning and Super Heavy Load Analysis

Chapter 1 Introduction

Contents: Section 1 - Manual Overview…..…… ...... 3 Section 2 - Policy Overview.………………………………………………………….…..1-4 Section 3 - Training .....………………………………………………………………….…..13 Section 4 - Contacts…...... 15

Section 1 Manual Overview

Purpose

The purpose of this manual is to provide the Texas Department of Transportation (TxDOT), consultant firms, and contractors a detailed pavement overview covering materials, design, construction, and maintenance considerations for traditionally-let TxDOT projects. The guide: serves as an extensive pavement reference that users can browse to look up typical design values, methods, practices and resources provides approved policies and procedures for pavement design for use on TxDOT projects provides pavement engineers with a uniform, streamlined process for designing pavements

includes a list of available training courses for pavement engineers and links to web-based training for pavement design and analysis programs used by TxDOT serves as a guide to pavement engineers for selecting pavement rehabilitation strategies addresses related topics that a pavement engineer needs such as procedures for changing load zones, super heavy load analysis and premature distress investigations.

Comprehensive Development Agreements

Comprehensive Development Agreements (CDAs) are comprised of contracting methods that include design, construction and maintenance of highways. Under CDAs, there are two major types of projects: concession and non-concession.

Concession projects require a long-term (more than 20 years) maintenance agreement. In this case, performance (ride, rut, distress, etc.) requirements are defined as criteria to be maintained on the project throughout the term of the agreement.

Non-concession projects have a short-term or no maintenance agreements. In this case, design and construction specifications are prescribed for projects.

The scope of this manual includes only traditional TxDOT projects.

Organization

This manual is organized into thirteen chapters: Chapter 1, Introduction. This chapter provides an overview of the guide, policy overview, a list of the training courses related to pavements and highway materials and also provides contacts for pavement and materials related topics. Chapter 2, Pavement Design Process. This chapter provides definitions of pavement types, pavement type selection, the approved methods for pavement design, pavement design categories, pavement design process, information needed for pavement design, and pavement design reports. Chapter 3, Materials Investigation and Selection Information. This chapter covers geotechnical investigations, stabilization guidelines, aggregate types and classes, performance graded binders (PG binders), asphalt pavement (ACP) mixtures, Portland concrete (PCC) and also geosynthetics. Chapter 4, Pavement Evaluation. This chapter provides an overview of pavement evaluation and non-destructive testing for pavements. Chapter 5, Flexible Pavement Design. This chapter provides an overview of the types of flexible pavements, design parameters and typical ranges, pavement detours and widening, and perpetual flexible pavement design.

Chapter 6, Flexible Pavement Construction. This chapter covers subgrade and base construction, surface preparation, plant operation, mix transport, mix placement, and compaction. Chapter 7, Flexible Pavement Rehabilitation. This chapter covers the different rehabilitation options for flexible pavements including hot in-place recycling, cold in-place recycling, geosynthetics, flexible base thickening, full depth reclamation, hot-mix asphalt (HMA) overlays, whitetopping and surface treatments. Chapter 8, Rigid Pavement Design. This chapter covers the approved pavement design methods for rigid pavements, rigid pavement design process, recommended typical values, thickness determination, concrete paving standards and thin whitetopping. Chapter 9, Rigid Pavement Construction. This chapter covers construction of subgrade and base, surface preparation, concrete mix design, concrete plant operation, delivery of concrete, steel placement, fixed form paving, slip-form paving, joints and texture requirements. Chapter 10, Rigid Pavement Rehabilitation. This chapter covers the different rehabilitation options for rigid pavements including full-depth repair, half-depth repair, bonded and unbonded concrete overlays, stitching, dowel bar retrofit, joint repairs, diamond grinding, thin ACP overlays, and retrofitting concrete shoulders. Chapter 11, Ride Quality. This chapter briefly discusses the units of measurement, equipment for evaluating ride quality, pay schedules, smoothness opportunities, and analysis of ride data. Chapter 12, Premature Distress Investigations. This chapter provides an overview of premature pavement failures, investigation team responsibilities and investigation process. Chapter 13, Load Zoning and Super Heavy Load Analysis. This chapter covers the procedures for changing load zones on highways (including county and bridges), procedure for setting emergency load zones on roads, super heavy load analysis, damage from super heavy load moves and damage claim procedure.

Section 2 Policy Overview

The following table summarizes the pavement design and construction policies required by the department. Section Policy Additional References Chapter 2 Pavement Design Process Section 2 District SOP: The district pavement engineer (DPE) will review and update the District Pavement Standard Pavement Operating Procedures (SOP) on an annual basis. This SOP Design shall be reviewed and updated by September 1st annually Standard with a copy emailed to CST-M&P. If no changes are made Operating from the previous year, send an e-mail to CST-M&P Procedure confirming that no changes were made. (SOP) Pavement Design Communication: The district engineer (DE) is responsible for documenting communication channels for designing, constructing, and maintaining quality pavements. Pavement Design Approval: Authority for pavement design approval may not be delegated below the DE, except for metropolitan districts. In metropolitan districts, pavement design approval authority may be delegated to the deputy district engineer, district director of construction, operations, or transportation, planning and development for projects with estimated construction cost of less than $20 million. Section 3 DPE: The DPE is a licensed professional engineer who Section 3 lists general serves as the district point of contact for the evaluation, responsibilities for DPE. District preservation, and structural design of pavements. Pavement Engineer’s Role Training: The DPE is required to receive approved training Other recommended in the use of MODULUS, FPS, AASHTO 1993 CPCD courses for pavement procedure, and TxCRCP-ME design software. materials and pavement management are included in this section. Section 5 Pavement Type Selection: The decision factors considered Section 5 includes some for pavement design type shall be included in the discussion on decision Pavement Type pavement design report. factors and