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24 whether the state would be more or less likely to use the new d) Width--Routine issue up to 14 ft wide. specifications, 12 said more likely and 17 said less likely. How- e) Trunnion Axle--A short axle pivoted at or near its mid-point. Normally used in pairs in conjunction with ever, when asked the same question but with the additional con- a walking beam in order to achieve two axles of dition that Virtis could be used to apply the new specifications, oscillation. 22 states said more likely, whereas 4 still said less likely. 3) Uniform Permit Information A uniform application form for permits is to be used by every state which shall be valid on a single trip for a mini- mum of 5 days excluding holidays. There shall also be a AASHTO BRIDGEWARE system in every state in which revisions or extensions may be obtained. Virtis is an AASHTO BRIDGEWare product that can be used 4) Blanket Permits and Self-Issue Endorse the concept of Blanket Permits by states on an for bridge load rating and bridge evaluation for permit review. annual basis. Usage would be available to all domiciled It has the graphical tools to speed preparation of the data and and nondomiciled motor carriers. application of the results. It uses the Wyoming DOT's program Self-issue permits would apply to single trips only. Bridge Rating and Analysis of Structural Systems (BRASS) as Self-issue permits would be completed by the holder of the self-issue forms after communicating with the ap- its analytical engine for load rating. Another important feature propriate governing agency. Usually, a permit number of Virtis is its integrated database where rating inputs and out- routing of some other specified piece of information is puts can be readily stored, reviewed, and reused. This feature given to each person completing the form. can make bridge load rating and bridge evaluation results more 5) Sign and Flag Uniformity Loads exceeding 8 ft 6 in. will have appropriate signs. uniform, because of the repeated use of the same data with min- All overdimensional loads will require signs. Required load imal updating. Through the comprehensive database and other signs should be the following dimensions: 7 ft wide by interactive functions, the user may provide a 3-dimensional de- 18 in. high with black letters 1-1/2 in. wide and 10 in. high scription of a bridge superstructure. These bridge data can then on yellow background reading "OVERSIZE LOAD" in front and rear locations. be used by a variety of girder-line, 2-dimensional, or 3-dimen- 6) Escort Vehicle Requirements sional analysis packages for permit and routing review. a) Length--One rear escort after 90 ft overall length on less than 4-lane highway and after 110 ft on 4 or more As discussed previously, a number of states have started lane highways. b) Width--One escort required on all loads when in ex- their implementation of Virtis, which requires that a large cess of 13 ft wide. Additional escort required on less amount of information be loaded in the database. The payoff than 4-lane highways when in excess of 14 ft wide. for this loading is that detailed information on the bridges c) Height--One escort required in excess of 14 ft 6 in. loaded height. within the jurisdiction will be available electronically. As a d) Weight--No routine escort service required. result, a higher consistency of bridge evaluation for permit e) Escort vehicles shall be equipped with two roof- review can be expected. mounted 18 in. red flags. Whenever the vehicle is es- corting a load requiring the overdimensional load sign, the escort shall display a bumper-mounted yellow 14 in. 5 ft sign reading "OVERSIZE LOAD" with black UNIFORM OVERDIMENSIONAL letters 8 in. high and 1-1/2 in. wide. Wherever special AND OVERWEIGHT PERMIT POLICY PROPOSED lights are required, a revolving amber dome light, meet- BY SPECIALIZED CARRIERS & RIGGING ing the requirements of SAE J845, mounted in the cen- ASSOCIATION ter of the vehicle roof, shall meet the state's special lighting requirements. The SC&RA is an organization representing member com- 7) Periods of Travel Under Permits a) Overweight loads only: overweight loads that are not panies involved in transportation of oversize and overweight overdimensional and can flow with the traffic shall be items. From a viewpoint of carriers, and with consideration allowed continuous travel. to state agency positions and practices, SC&RA developed a b) Overdimensional loads 10 ft wide or less shall be al- uniform overdimensional/overweight permit policy as a ba- lowed continuous travel. c) Overdimensional loads exceeding 10 ft wide shall op- sis for a position on uniformity in permit policy. This policy erate in daylight hours only. is presented here. d) Vehicles under permit shall be prohibited from travel on the following holidays: New Year's, Easter, Memorial 1) Any state, which, based on safety considerations has es- Day, Independence Day, Labor Day, Thanksgiving and tablished limits in excess of those found in this proposal, Christmas. should continue such limitations and practices. 2) Routine Issue: This refers to any overdimensional/over- weight permit that would not exceed provisions covered by SC&RA recognizes that there would be modifications by the Uniform Permit Policy. states to this uniform policy; however, this can be a founda- a) Height--Limited by route only. tion toward enhanced uniformity for the OS/OW permit prac- b) Length--Routine issue up to 120 ft. c) Weight--Routine issue for combinations not to exceed tice. In item (3) of the uniform policy, a concept of uniform 22,000 lb per axle and/or combination weights as follows: permit information is proposed toward the direction of a uni- Axle Weight (in lb) form permit application form. Figure 10 displays SC&RA's Single (Dual Tire) 22,000 Tandem 46,000 proposed information form. On the other hand, SC&RA does Tri 60,000 recognize that each state has its own forms for a variety of Trunnion 60,000 reasons.