Life-time reliability based optimization of bridge maintenance strategy considering LCA and LCC

Depth estimation of surface-opening crack in concrete beams using impact-echo and non-contact video-based methods

“…The crack depth was then calculated as 6.22 cm according to Eqs. (1) and 3. Figure 9 clearly shows that the cracks on 12-1#, 12-2#, 12-3#, and 16-1# beams were all vertical cracks.…”

“…8 Test configuration for the travel velocity of P-wave Table 2 Theoretical ultimate load and applied load when visible crack occurs for each specimen Eqs. (1) and 3, the crack depth determined by the IE method was calculated as 6.24 cm. The most evident crack for the 12-2# beam emerged at 6.4 cm left to the mid-span of the beam (Fig.…”

“…Then, the crack depth for the 12-2# beam was estimated as 5.61 cm according to Eqs. (1) and (3). For the 12-3# beam, the most evident crack appeared at 13.7 cm right to the mid-span of the beam (Fig.…”

“…10e), and the crack depth was calculated as 7.88 cm according to Eqs. (1) and (3). Similarly, the distance values of H 1 , H 2 , and H 3 for the 16-3# beam were designed as 0.10, 0.05, and 0.12 mm, respectively, and the difference in the arrival time for the P-wave to the two sensors was 0.000026 s (Fig.…”

“…However, most of the bridges constructed decades ago have experienced different levels of degradation after being subjected to long-term environment attacks and load effects. The USA spend approximately $10 billion annually on the repair and maintenance of their existing bridges [1]. Surface-opening crack is one of the most common defects for concrete bridges; it reduces stiffness and allows aggressive media, such as water and chloride, to corrode the reinforced bars, thereby causing the loss in load-carrying capacity.…”