Assessing the Seismic Performance of Exterior Precast Concrete Joints with Ultra-High-Performance Fiber-Reinforced Concrete

International Journal of Concrete Structures and Materials

Table 6 Comparisons between test results and ACI 374.1-05 acceptance criteria (2)

		Acceptance criteria	PJ-CUS ( +)	PJ-CUS (–)	PJ-CU-C ( +)	PJ-CU-C(–)	PJ-CUS-C ( +)	PJ-CUS-C (–)
	\(\frac{{M}_{peak}}{{M}_{n}}\)	≤ 1.25	1.06	0.99	0.97	1.06	1.06	1.07
During third cycle of 4% drift cycles	\(\frac{{M}_{3rd}}{{M}_{peak}}\)	≥ 0.75	0.94	0.94	0.95	0.94	0.94	0.95
	\(\beta\)	≥ 1.25	1.394		1.359		1.295
	\(\frac{{K}_{s}}{K}\)	≥ 0.05	0.17	0.20	0.26	0.18	0.18	0.19

M_n: nominal beam moment strength (calculated based on measured material properties)
M_peak: peak beam moment (measured)
M_3rd: peak beam moment during 3rd cycle of 4.0% drift ratio (measured)
β: relative energy dissipation ratio (ACI 374.1–05)
K_s ( +): secant stiffness for positive loading* from a drift ratio of − 0.35% to a drift ratio of + 0.35% (ACI 374.1–05)
K_s (–): secant stiffness for negative loading** from a drift ratio of − 0.35% to a drift ratio of + 0.35% (ACI 374.1–05)
K ( +): initial stiffness for positive loading* for first cycle (ACI 374.1–05)
K (–): initial stiffness for negative loading** for first cycle (ACI 374.1–05)
^*Positive loading, defined as loading from right to left (see Fig. 5)
^**Negative loading, defined as loading from left to right (see Fig. 5)