FLORENCE & HUTCHESON LEE SEWELL, PE, SE

 SIGNAL AND LIGHTING STRUCTURAL ANAYLSIS (SALSA)  ANALYZES WIRE SPAN, MAST ARM AND HIGH MAST STRUCTURES

 STARTED IN 2007 ◦ EXPAND ON EARLIER GEOTECHNICAL EVALUATIONS DONE BY DARRIN BECKETT IN  AT THE TIME, POLE BASES DIDN’T HAVE DOCUMENTED DESIGN. ◦ 10FT BASE  BRING THE DESIGN UP TO CURRENT CODE. ◦ AASHTO STANDARD SPECIFICATIONS FOR STRUCTURAL SUPPORTS FOR HIGHWAY SIGNS, LUMINAIRES AND TRAFFIC SIGNALS.

 REMOVE THE NEED FOR PERFORMING SITE- SPECIFIC GEOTECHNICAL INVESTIGATIONS.  CHALLENGES ◦ ENCOMPASS ALL TYPES OF SOIL THAT COULD BE ENCOUNTERED ◦ CONSERVATISM

 MODELED FOUNDATIONS UNDER VARYING SOIL AND SLOPE CONDITIONS. ◦ COHESIVE AND COHESIONLESS SOILS AND ROCK  COHESION = 1 KSF  FRICTION ANGLE = 30 DEG ◦ 3:1, 2:1, 1.5:1

 DIAMETER ◦ DRIVEN BY ANCHOR BOLT CIRCLE OF POLES  36” MAST ARM AND WIRE SPAN POLES  48” HIGH MAST  EMBEDMENT (AASHTO ) ◦ BROMS DESIGN METHOD  BASED ON ULTIMATE STRENGTH DESIGN, SO SAFETY FACTORS ARE APPLIED TO SHEARS AND MOMENTS.

◦ BROMS DESIGN METHOD ◦ SAFETY FACTORS (AASHTO RECOMMENDS)  UNDERCAPACITY FACTOR OF SOIL: 0.7  OVERLOAD FACTOR FOR LOADINGS: 3  SAFETY FACTOR = 4.3 ◦ THE HIGH SAFETY FACTORS WERE AGREED ON BY THE GEOTECHNICAL DEPARTMENT DUE TO THE UNCERTAINTY OF THE TYPE OF SOIL.

 DESIGN TABLE DEVELOPED

 AASHTO SECTION 3: LOADS ◦ OUTLINES LOADING ON POLES AND ATTACHMENTS  SALSA IS USED TO FIND LOADS ON POLE BASES

 ANALYZES WIRE SPAN, MAST ARM AND HIGH MAST STRUCTURES  MAST ARM AND HIGH MAST LOADS ARE FOUND BY SIMPLE STATICS  SPAN WIRE ANAYLSIS ◦ DETAILED METHOD OF ANALYSIS ◦ AASHTO A8

 MAST ARM AND HIGH MAST ◦ LOADING FOR BASE DESIGN  WIRE SPAN ◦ LOADING FOR BASE DESIGN ◦ LOADING FOR POLE SELECTION FROM STORAGE YARD

 WIRE SPAN POLE SELECTION ◦ PREVIOUS DESIGN  IN-HOUSE SPREADSHEET FOR WIRE SPAN STRUCTURES  NEGLECTED WIND AND ICE LOADS ◦ SALSA  CALCULATES MOMENTS COMPARES THEM TO THE ALLOWABLE MOMENTS FOR POLES IN THE YARD.

 PROBLEMS ◦ EXCEL COMPATIBLITY ◦ DELIVERY ◦ LIMITATIONS

 MOVING TO A WEB BASED APPLICATION

 WEB BASED ADVANTAGES ◦ GREATER ACCESS ◦ FILE SHARING ◦ UPDATES ARE SEAMLESS ◦ MORE USER FRIENDLY

 POSSIBLE ADVANCEMENTS ◦ STATEWIDE SOIL PROFILING ◦ ADDITIONAL FEATURES  POLE BASE VOLUME CALCULATOR  ATTACHMENT HEIGHT PLACEMENT