Section 2: Recommended Temporary Railing
Anchor: #i998977Precast Safety-shaped Traffic Barriers
For temporary railing, TxDOT recommends the single-slope concrete barriers (SSCB) or the F-shaped concrete barriers (CSB) detailed in the Roadway Standard drawings. You may use existing precast safety-shaped traffic barriers such as the concrete traffic barrier (CTB), also found in the Roadway Standard drawings. Other acceptable temporary railings include the T503 or, for design speeds of 45 mph or less, the T6 railing.
Available railing slide space should influence a decision whether to anchor the barrier: crash-test vehicle performance is better with the unanchored barrier; however, unanchored barriers can pose a threat to lower roadways. TxDOT does not recommend using unanchored precast safety-shaped traffic barriers unless at least two feet of slide space is available behind them to allow the energy of an impact to be absorbed by the change in momentum of the barrier mass. See the Roadway Standard drawing CSB(7)-04 for details to anchor CSB, and standard drawing PCTB(3)-94 for details to anchor CTB.
Length of the construction area can also be a factor in selection of this railing. If barrier segments are 30 feet long, they can be connected easily with only nominal equipment. However, to perform adequately as a temporary railing, 10-ft. segments require significant connection in the form of dowels, cables, bolted lap splices, and so on. Most Texas precast barriers are in 30-ft. segments, and TxDOT generally discourages use of shorter segments for temporary bridge railing.