UNITED STATES DEPARTMENT OF AGRICULTURE 



;f BULLETIN No. 1077 ^» 



Washington, D. C. 



October 21, 1922 



PORTLAND CEMENT CONCRETE ROADS. 



By James T. Voshell, District Engineer, and R. E. Toms, Senior Highway 

 Engineer, Bureau of PiiMic Roads. 



CONTENTS. 



Introduction 1 



Materials used in concrete roads 3 



Cement 3 



Pine aggregate 3 



Coarse aggregate 4 



Water 5 



Reinforcement 6 



Proportioning 6 



Quantities of materials required 10 



Design 10 



Width of pavement 11 



Thickness of pavement 12 



Crown of pavement 14 



Superelevation of curves 15 



Widening on curves 16 



Joints 17 



Steel reinforcement 23 



Shoulders and ditches 24 



Curbs and gutters _ 25 



Bituminous surface treatment- _ 25 



The cross-section 27 



Construction 27 



Grading 27 



Drainage 27 



Page. 



Consti'uction — Continued. 



Preparation of the subgrade 20 



Forms 30 



Handling and hauling materials- 31 



Mixing and placing 40 



Finishing the surface 42 



Protecting and curing the con- 

 crete 46 



Placing concrete in freezing 



weather 47 



Organization and equipment 47 



Capital required 55 



Cost of concrete pavements 55 



Maintenance 58 



Resurfacing old concrete pavements_ 59 



Appendix 61 



A. Quantities of materials re- 



quired 61 



B. Tables for determining the 



size of pump required for 



delivering water 63 



C. Cost of Federal-aid concrete 



pavements 64 



INTRODUCTION. 



The purpose of this bulletin is to supply reliable information on 

 the subject of concrete pavements for the use of highway engineers 

 and others interested in the improvement of public roads. The meth- 

 ods of construction described are believed to represent the best prac- 

 tice at this time ; but, as experience and research are continually sug- 

 gesting improvements, those who have charge of concrete-road con- 



101130°— 22 1 



