SPECIAL DESIGN FEATURES OF BAYTOWN VEHICULAR TUNNEL

THE TUNNEL IS 3,000 FEET BETWEEN PORTALS, WITH OPEN APPROACHES 550 FEET LONG ON EACH END, CARRIES TWO-WAY TRAFFIC ON A ROADWAY 22 FEET WIDE BETWEEN CURBS WITH A MINIMUM VERTICAL CLEARANCE OF 14 FEET AT THE CURB LINES, AND PROVIDES FOR THE FUTURE WIDENING OF THE SHIP CHANNEL TO 700 FEET AND ITS DEEPENING TO 40 FEET. ROADWAY GRADE FROM THE MIDPOINT TO THE FUTURE CHANNEL LINES IS 1 PERCENT, AND FROM THERE TO THE UPPER END OF THE OPEN APPROACHES THE MAXIMUM GRADE IS 5.83 PERCENT. THE MAJOR PART CONSISTS OF NINE SUNKEN TUBE SECTIONS, SIX OF 300 FEET AND THREE OF ABOUT 250 FEET LENGTH. THEY WERE CONSTRUCTED AS CIRCULAR STEEL SHELLS 34 FEET, 10 INCHES IN DIAMETER, WITH AN INTERIOR LINING OF 30 INCHES OF REINFORCED CONCRETE PLACED WHILE THE SHELLS WERE FLOATING AT THE CONSTRUCTION SITE. THE TUBES WERE SUNK INTO A TRENCH DREDGED ACROSS THE CHANNEL, IN WHICH WAS PLACED A SAND FOUNDATION COURSE 3 FEET THICK. STEEL SCREEDS LEVELLED THIS COURSE TO PROPER GRADE. THE SECTIONS WERE JOINTED AND SEALED UNDER WATER, TO PERMIT ENTRANCE AT THE ENDS AND REMOVAL OF INTERIOR BULKHEADS. CUT-AND-COVER SECTIONS AND OPEN APPROACHES ARE REINFORCED-CONCRETE STRUCTURES, PROTECTED BY OUTSIDE MULTI-PLY WATERPROOFING. PART OF THE NORTH CUT-AND-COVER SECTION WAS BUILT INTO THE VENTILATION BUILDING. THE OPEN APPROACHES, VENTILATION BUILDING AND CUT-AND-COVER SECTION BETWEEN THE NORTH PORTAL AND THE VENTILATION BUILDING ARE SUPPORTED ON PILES. TO ALLOW FOR DIFFERENTIAL SETTLEMENT BETWEEN PILE-SUPPORTED STRUCTURES AND PARTS RESTING DIRECTLY ON SOIL, A SHORT LENGTH OF EACH CUT-AND-COVER TUNNEL WAS DESIGNED TO FORM AN ARTICULATED JOINT, WHICH REQUIRED DEVELOPMENT OF CONNECTIONS WHICH COULD TRANSMIT SHEAR, PERMIT DEFLECTION, YET BE WATERTIGHT. JOINTS BETWEEN SUNKEN TUBES HAD TO BE DESIGNED TO PERMIT SUFFICIENT PLAY DURING THE SINKING OPERATION, BUT REMAIN SUITABLE FOR SEALING FROM THE OUTSIDE BY SIMPLE METHODS. A METHOD WAS DEVELOPED TO PRODUCE ECONOMICALLY A SATISFACTORY APPEARANCE OF THE EXPOSED CONCRETE SURFACES OF THE OPEN APPROACHES. THIS WAS OBTAINED BY THE USE OF SIMPLE, SQUARE-FORM PANELS MADE OF ROUGH-SAWN LUMBER. INVESTIGATION OF AIR FLOW INDICATED A LONGITUDINAL VENTILATION SYSTEM, SUPPLYING FRESH AIR THROUGH A DUCT BELOW THE ROADWAY AND EXHAUST OF VITIATED AIR THROUGH THE PORTALS, WOULD BE SATISFACTORY. A FLUORESCENT TUNNEL-LIGHTING SYSTEM WITH HIGH INTENSITY AT THE PORTALS WAS DESIGNED. INVESTIGATIONS OF SUITABLE PLASTICS FOR THE COVERS WERE MADE, WITH PLEXIGLASS AS THE FINAL SELECTION. THE DRAINAGE SYSTEM WAS DESIGNED FOR MAXIMUM RAINFALL AT THE RATE OF 4 INCHES PER HOUR AND FOR A 10-MINUTE DOWNPOUR AT 8 INCHES PER HOUR. DEEPWELL PUMPS AND BOOSTER PUMPS SUPPLY THE FIRE MAIN AND HOSE OUTLETS IN THE TUNNEL. TELEPHONE AND FIRE-ALARM SYSTEMS WERE PROVIDED. /AUTHOR/

  • Supplemental Notes:
    • Vol 33, pp 54-64, 5 FIG
  • Authors:
    • Bickel, J O
  • Publication Date: 1954

Media Info

  • Monograph Title: Proceedings of the Thirty-Third Annual Meeting of the Highway Research Board, Washington, D.C., January 12-15, 1954
  • Serial:

Subject/Index Terms

Filing Info

  • Accession Number: 00236023
  • Record Type: Publication
  • Files: TRIS, TRB
  • Created Date: May 9 1972 12:00AM