COUNTY DIVISIBLE LOAD PERMITS ISSUED IN 2013 PERMIT FEES PERMITS?

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3 COUNTY DIVISIBLE LOAD PERMITS ISSUED IN 2013 PERMIT FEES PERMITS? GARFIELD NO Single OS - 57 Single Trip OS $15.00 Single OW Single Trip OW $ $5.00/axle Single OS/OW Annual OS $ Annual OS - 22 Annual OW $ Annual OW - 23 Annual OS/OW $ Annual OS/OW Extraordinary $ $ $5.00/Axle Extraordinary - 51 TOTAL 1,897 RIO BLANCO No Single OS 75 Single Trip OS $15.00 Single OW Single Trip OS/OW $ $5.00/Axle Single OS/OW 331 Annual OS $ Annual OS 47 Annual OS/OW $ Annual OW Annual OW $ Annual OS/OW 222 Special Permit $65.00 or Actual RBC costs Extraordinary 18 Transfer Fee $15.00 TOTAL 693 MESA Yes Their Divisible Load Regs Annual Permits 363 Single Trip Extra-Legal $15.00 currently shadow the States. Single Permits 83 Single Trip Extra Ordinary $65.00 They are in the process of SOU 94 Single Trip EO w/ an Annual $50.00 re-doing their Regs to permit Single Divisible Load 0 Annual Extra Legal Permit $90.00 Divisible loads on Primary Annual Divisible Load 32 Annual Divisible Load OW $90.00 Roads only, these roads being built to State Spec to handle the TOTAL 572 excess weight. MOFFAT No Single Trip OS 222 Single Trip OS $15.00 Single Trip OW 2 Single Trip OS/OW $ $5.00/Axle Single Trip OS/OW 75 Annual OS/OW $ Annual OS/OW 17 Annual Fleet $ $25.00/unit Special Use 175 Special Permit $ TOTAL 491 State of Yes - On State Secondary OS Annual $ Colorado Roads only OW Annual $ OSOW Annual $ Single Trip OS $ Single Trip OS/OW $ $10.00/axle Additional State Permitting as shown on State Permit application

4 MEMORANDUM TO: Deb Fiscus FROM: Mike Fowler, P.E. and Dan Cokley, P.E. DATE: April 16, 2014 SUBJECT: Bridge and Pavement Analysis for Overweight Divisible Loads SGM has performed an engineering evaluation of bridges and pavement sections for two separate overweight, divisible load permit trucks. The first truck that has been used in the evaluation is a 79,000 pound, single-unit, quad axle water truck based on the information provided by Gonzo Trucking. The second truck is a 94,000 pound, single-unit, quad axle dump truck that is similar to what is currently being permitted in neighboring counties. Colorado Legal Load Limits (no permit required) The maximum gross weight allowance on any non-interstate highway is 85,000 pounds. The total weight must be distributed so that no axle weight exceeds the legal axle weight limit for the highway traveled. This vehicle must also comply with the State Bridge Formula (see below). [C.R.S (1)(b)] The maximum gross weight allowance on any interstate highway is 80,000 pounds. The total weight must be distributed so that no axle weight exceeds the legal axle weight limit for the highway traveled. This vehicle must also comply with the Federal Bridge Formula (see below). [C.R.S (1)(c)(III)] Bridge Formulas Colorado State bridge formula for non-interstate highways: W=(L+40)1000 Federal bridge formula for interstate highways: W=500[(LN/N-1)+12N+36] W=weight; L=length from center of 1st axle to center of last axle; N=number of axles Both the 79,000 pound and 94,000 pound trucks were evaluated using both bridge formulas and both trucks violate each of the formulas. These results are presented in the attached calculations. Colorado Maximum Load Limits (permit required) Colorado House Bill allows an overweight vehicle to be permitted with a maximum gross weight of 97,000 pounds if it is operated in combination with a trailer or semitrailer if the trailer has a tandem or triple axle grouping. Colorado House Bill allows an overweight vehicle to be permitted with a maximum gross weight of 110,000 pounds if the vehicle has a quad axle grouping. 118 W. 6 th St, Ste 200 Glenwood Springs, CO Phone: Fax:

5 Bridge Evaluation SGM has evaluated the two different truck loading configurations for simple span bridges up to 140 in length. Bending moments and vertical shear forces were calculated for each of the trucks and the results are compared to moments and shears for a standard 72,000 pound AASHTO HS-20 Design Truck. Bending moments are used to determine stresses in beams due to flexure. Bending moments typically control the design for beams of various materials (steel, concrete and timber). Vertical shear forces typically do not control beam design, but may control the design of concrete slabs near the ends of the slab members where they are supported by walls or abutments. An example of where vertical shear force may control a design is in the top slab of a concrete culvert where it is supported by the sidewall. In general, the 79,000 pound and 94,000 pound single-unit, quad axle truck loadings result in the largest percentage increase over the design truck in the 15 to 40 span range. The worst case for each of the quad axle trucks is for a 24 span length. As shown in the following table, for a 24 long bridge the 79,000 pound truck produces a bending moment that is 23% greater than the HS-20 truck and the 94,000 pound truck produces a 58% greater bending moment compared to the HS-20 truck. SPAN MOMENTS (kip-ft) LENGTH HS20 79k QUAD 94k QUAD (ft) M Max M Max % of HS20 M Max % of HS % % % % % % % % % % % % % % % % % % % % % % % % % % % % % % % % % % % % This general analysis is only valid for single span bridges and it should be noted that there are a number of multi-span bridges in the County s inventory that would require additional evaluation to provide similar comparisons. 118 W. 6 th St, Ste 200 Glenwood Springs, CO Phone: Fax:

6 Pavement Evaluation SGM has evaluated the 18,000 pound (18 k) Equivalent Single Axle Load (ESAL) loadings for the vehicles shown in the Pavement Analysis Trucks exhibit on the following page. For each vehicle, an ESAL loading per trip and a corresponding water volume carried per ESAL was calculated. See table below for loaded vehicle comparison: VEHICLE TOTAL LOAD (lbs) WATER CAPACITY (bbls) ESAL LOAD FACTOR CAPACITY PER ESAL (bbl / ESAL) WB-50 Tanker 80, Bobtail 54, K Quad Tanker 79, k Quad Dump 94,000 N/A 6.52 N/A As the Table indicates, The WB-50 Tanker is the most efficient carrier of water in regard to loading on a pavement surface due to its distribution of weight across a longer vehicle with tandem axles. The proposed Gonzo Quad is more efficient from a water hauling and pavement loading perspective in comparison to the existing Bobtail vehicle due to a higher relative load volume. While the existing WB-50 Tanker and Bobtail vehicles are similar with regard to ESAL loading per trip, the proposed Quad vehicles have a resultant load factor of 1.5 to 3 times the existing vehicles in use. The Quad vehicles will produce higher ESAL loadings over time and require increased pavement sections than would the existing vehicles currently being used for water hauling and gravel operations. Attachments: Bridge Analysis Calculations cc: Project File I:\2014\ GarCoRB\001-BrPermitEval\A-Corresp\BOCC Memo docx 118 W. 6 th St, Ste 200 Glenwood Springs, CO Phone: Fax:

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8 BRIDGE ANALYSIS CALCULATIONS

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10 BRIDGE FORMULA CALCULATIONS FOR 79,000 LB QUAD AXLE TRUCK U.S. BRIDGE FORMULA COLORADO BRIDGE FORMULA Axle Weight (lbs) Axle Weight (lbs) Bridge N L (ft) Allow Actual Bridge L (ft) Allow Actual = = = U.S. Bridge Formula Violation = Colorado Bridge Formula Violation

11 BRIDGE FORMULA CALCULATIONS FOR 94,000 LB QUAD AXLE TRUCK U.S. BRIDGE FORMULA COLORADO BRIDGE FORMULA Axle Weight (lbs) Axle Weight (lbs) Bridge N L (ft) Allow Actual Bridge L (ft) Allow Actual = = = U.S. Bridge Formula Violation = Colorado Bridge Formula Violation

12 SIMPLE SPAN ANALYSIS SUMMARY SPAN MOMENTS (kip-ft) LENGTH HS20 79k QUAD 94k QUAD HS20 SHEARS (kips) 79k QUAD 94k QUAD (ft) M Max M Max % of HS20 M Max % of HS20 V Max V Max % of HS20 V Max % of HS % % % % % % % % % % % % % % % % % % % % % % % % % % % % % % % % % % % % % % % % % % % % % % % % % % % % % % % % % % % % % % % % % % % % % % % % % % % % % % % % % % % % % % % % % % % % % % % % % % % %

13 Maximum Moments Simple Spans to 140' , , , M Max (kip-ft) , , , , , , , , k Quad , k Quad HS Bridge Span (ft)

14 700 Maximum Moments Simple Spans to 40' M Max (kip-ft) k Quad k Quad HS Bridge Span (ft)

15 100 Maximum Shears Simple Spans to 140' Shear (kips) k Quad 79k Quad 10 HS Bridge Span (ft)

16 80.00 Maximum Shears Simple Spans to 40' Shear (kips) k Quad k Quad HS Bridge Span (ft)

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