DURA® TBG - T Bridge Girder
DURA® TBG is prefabricated using the revolutionary composite material of ultra-high performance concrete and high-carbon-high-tensile steel fibres (UHPdC). It is an excellent solution for bridge engineers looking for a cost effective, fast construction, light-weight and high-durability option for bridges with a span range of 15 to 30m.
- DURA® TBG are typically prestressed to 70~80% of the 'guaranteed' tensile strength of the strands. Strands used are 15.2 mm diameter 7-wire super strands (low relaxation) complying with AS 1311; with a guaranteed tensile load of 250 kN and ultimate breaking load of 270 kN.
- The UHPdC of the DURA® TBG has characteristic compressive strength range between 120 to 140 MPa, and characteristic flexural strength of 20 MPa.
- DURA® TBG eliminates the used of conventional steel reinforcing bars and stirrups, except at regions where jointing detail are needed during construction. All steel fibers used are made from high carbon steel wires with tensile strength of minimum 2300 MPa.
Advantages of DURA® TBG
- DURA® TBG is highly durable and impermeable. It is therefore suitable for use even in harsh environments.
- DURA® TBG is unique as the tops of the units make up the entire deck slab to form a "full-deck" beam thus eliminating the formwork of the superstructure. Together with carefully planned detailing, the construction process can be shortened considerably, resulting in overall cost and time savings.
- No scaffolding, props or formwork are required over the supports, thus reducing construction site activities, improving safety margins and eliminating in-situ casting work (except construction of the joints and minor details).
- Ease of handling/transportation and installation - DURA® TBG is significantly thinner in section and at least 50% lighter than conventional beams. This weight efficiency also leads to further optimization of the foundations and support structures; at the same time contributing to a sustainable development regime.
- DURA® TBG can be produced to required lengths with increment of 0.5 m. Spans outside the indicated range can be considered on request.
Detail of DURA® TBG
Figure 1: Elevation View
Figure 2: Cross Section
Table 1: Technical Data for Pre-Tension DURA® TBG
|Type of Prestressing||Pretension||Post-tension||Pretension|
|Length||L||m||12 ~ 20||18 ~ 32||12 ~ 20|
|Sectional Area||Ag||x 103 mm2||348.2||418.5||331.7|
|Moment of Inertia||Ixx||x 109 mm4||34.16||98.186||44.302|
|Section Modulus||Ztop||x 106 mm3||113.87||206.07||106.47|
|Zbot||x 106 mm3||59.41||115.71||75.87|
↑ TBG875 and TBG1325 are designed for normal highway loading as per BD37/01.
↑↑ TBG1000 is customized for abnormal excessive high loading as per clients requirement. It is ideal for jetty bridge construction.
Strength Test and Results
Figure 3: Strength Test Setup
Figure 4: Photo shows 2 pieces of T875BG joined together
Graph 1: Experimental Flexure Strength Result of DURA® TBG
Graph 2: Experimental Shear Strength Result of DURA® TBG
Figure 5: Non-Linear Finite Element Modelling Result on 20m Span and 12m Wide Bridge using T875BG at Full 45HB Loading