SUBGRADE STUDIES OF THE U.S. BUREAU OF PUBLIC ROADS

SUBGRADE STUDIES WERE CONDUCTED TO DETERMINE: (1) THE PRACTICALITY OF VARYING THE TYPE OR DESIGN OF ROAD SURFACE TO SUITE SUBGRADE CONDITIONS, (2) THE EFFICIENCY OF VARIOUS TYPES OF DRAINAGE, SUBGRADE TREATMENT AND SUBBASES, AND (3) THE RELATIVE ECONOMY AND SUBGRADE REINFORCEMENT AND CHANGE IN PAVEMENT DESIGN AS COMPENSATION FOR VARYING SUBGRADE CONDITIONS. STUDIES OF ROADS IN SERVICE WERE CORRELATED WITH US BUREAUS OF SOILS DATA, LABORATORY TESTS ON SUBGRADE SOILS, AND OFFICE COST RECORDS. A COMPLETE OUTLINE IS GIVEN OF SUBGRADE STUDIES OF THE BUREAU, TOGETHER WITH A DESCRIPTION AND DISCUSSION OF THE ROAD SURVEY PROCEDURE. A METHOD IS PROPOSED FOR CORRELATING PAVEMENT CONDITION WITH SUBGRADE CHARACTERISTICS. THE SUMMARY RECORD OF CONDITIONS SURVEY IS THE ANALYTICAL DIGEST OF THE ENTIRE SURVEY. IT CONSISTS OF CONDENSED INFORMATION FROM WHICH DEDUCTIONS MAY BE DRAWN AS THE VARIABLES IN ONE ROAD AS COMPARED WITH SIMILAR VARIABLES IN ANOTHER PROJECT. THE INFORMATION IS OBTAINED DIRECTLY FROM THE PERMANENT RECORD CHARTS BY SCALING AND TOTALLING THE RESPECTIVE LENGTH OF THE INDIVIDUAL CULVERTS, FILLS, AND GRADE SECTIONS IN EACH SOIL TYPE. THE ORIGINAL GROUND LINE IS USED IN THESE COMPUTATIONS. THE RECORD SHOWS IN DETAIL THE SLAB CONDITION CORRESPONDING TO: (1) CUT, FILL, AND GRADE SECTIONS IN EACH SOIL TYPE, (2) EACH SOIL TYPE INCLUDING THE CUT, FILL AND GRADE SECTIONS, (3) CUT, FILL, AND GRADE SECTIONS IN ALL SOIL TYPES COMBINED, (4) THE ENTIRE LANGTH OF ROAD REPRESENTED BY THE SURVEY, AND (5) THE GEOLOGICAL CHARACTER OF THE SOIL. IN MANY SURVEYS, INFORMATION CONCERNING THE EFFECT OF THE SOIL TYPE AND CUTS AND FILLS UPON SLAB AND SURFACE CONDITION WOULD INCLUDE A RELATIVE SHOWING IN THE SUMMARY RECORD OF: (1) THE WIDTH OF CRACKS AND JOINTS, (2) THE REVELLING OF CRACKS AND JOINTS, (3) THE FAULTING OF SLABS, AND (4) THE SCALING OF THE SURFACE. DATA CONTAINED IN THE SUMMARY RECORD PERMIT RELATIONSHIPS TO BE ESTABLISHED BETWEEN THE SLAB OR SURFACE CONDITION AND THE RESULTS OF THE SOIL TESTS.

  • Supplemental Notes:
    • Vol 6, pp 113-133, 3 FIG, 1 TAB
  • Authors:
    • Hogentogler, C A
    • Mullis, I B
    • Benkelman, A C
  • Publication Date: 1927

Media Info

  • Monograph Title: Proceedings of the Sixth Annual Meeting of the Highway Research Board Held at Washington, D.C., December 2-3, 1926
  • Serial:

Subject/Index Terms

Filing Info

  • Accession Number: 00232867
  • Record Type: Publication
  • Files: TRIS, TRB
  • Created Date: Jun 11 1971 12:00AM