Cyclic Loading Test Conducted on the Bottom Joints of a Hybrid Precast Utility Tunnel Composed of Double-Skin Sidewalls and a Precast Bottom Slab

Abstract

Four full-scale specimens were constructed, including two hybrid precast specimens with a haunch (height: 150 mm, PUT-H) and without a haunch (PUT). Additionally, two cast-in-place (CIP) comparative specimens (referred to as RUT-H and RUT) were included, all of which underwent reversed cyclic loading. The results showed that the four specimens suffered flexural damage at the ends of the sidewall and displayed similar hysteresis loops shapes. The bearing capacity of the PUT specimen was 2.7% higher than that of the RUT, while the bearing capacity of the PUT-H specimen was 8.5% lower than that of the RUT-H. Additionally, the displacement ductility values of the precast specimens PUT and PUT-H were 2.98 and 2.46, respectively, which are 11.3% and 3.53% lower than those of the corresponding CIP specimens. The haunch increases the local stiffness of the component, exerting a notable influence on the bearing capacity and displacement ductility of the specimens, increasing the bearing capacity by 20% and decreasing the ductility by 21%. Moreover, an assessment conducted using the criteria outlined in ACI 374.1-05 indicated that the four specimens exhibit excellent seismic performance.

Prediction of Utility Tunnel Performance in a Soft Foundation during an Operation Period Based on Deep Learning

“…Moreover, based on a quasi-static experiment, the cross-sectional mechanical behavior of a prefabricated multi-cabin-reinforced concrete utility tunnel under free-field racking deformation by earthquake action has been studied [6]. Also, based on quasi-static load tests on the full-size model, the mechanical behavior of a prefabricated concrete utility tunnel and the seismic behavior of top joints for the hybrid precast utility tunnel consisting of the precast composite top slab and double-skin sidewalls with reserved rebar have been researched [7,8]. Based on the quasi-static cyclic tests for simulating earthquake action, the seismic performance of the precast concrete composite walls of utility tunnels with a grouting-sleeve connection out-of-plane has been studied [9].…”

Study of the Effect of Seepage–Cyclic Load Coupling Disturbance on the Physical Field in Old Urban Underground Spaces

“…Many researchers have investigated and analyzed this phenomenon and found that there are many reasons for early damage in civil air defense engineering, among which some of the principal reasons are seepage and cyclic loads [20][21][22][23]. The current research mainly focuses on seepage and traffic loads and roads, as well as the effect of speed on road surfaces [24][25][26][27].…”