Perilaku plat lantai jembatan gabungan beton Precast dan Cast-in-Place akibat beban terpusat

HIMAWAN, Lava, Dr.-Ing.Ir. Andreas Triwiyono

2005 | Tesis | S2 Teknik Sipil

Di dalam pembuatan plat lantai jembatan, plat beton pracetak biasanya digunakan sebagai bekisting beton cast-in-place (cip). Untuk meningkatkan efisiensi struktur, plat pracetak dapat digunakan sebagai bagian struktural plat komposit lantai jembatan. Penelitian ini bertujuan untuk mengetahui perilaku dan kekuatan plat komposit lantai jembatan yang mendapat beban terpusat statis. Model plat berukuran 1500mm x 725mm x100mm (skala 1:2). Plat komposit disusun dari plat pracetak tebal 35 mm dan plat cast-in-place tebal 65 mm. Keduanya dihubungkan dengan epoxy resin bonding agen (ERBA) Sikadur-732 untuk perkuatan geser bidang interface. Sementara di kelompok lain, beton pracetak dan cast-in-place digabungkan tanpa menggunakan ERBA. Beban roda dimodelkan sebagai beban lendutan nodal pada luasan 250mm x 100mm (aktual 500mmx200mm). Program komputer ATENA versi 2.1.8 (demo) digunakan untuk membantu menyelesaikan persamaan elemen hingga nonlinier, dan program komputer GID versi 7.4.4b untuk pemodelan geometri tiga dimensi. Hasil analisis menunjukkan bahwa nilai Pfirstcrack plat komposit yang diperkuat ERBA sekitar 5,18 ton (atau 20,72 ton untuk prototype). Nilai Pfirst crack hasil analisis 33,83% lebih kecil daripada hasil yang diperoleh dalam eksperimen. Beban runtuh plat komposit yang diperkuat ERBA adalah 33,26 ton (atau 133,04 untuk prototype). Beban runtuh plat komposit dengan dan tanpa erba berturut-turut 5,18% dan 10,24% lebih kecil dari kekuatan plat non-komposit (monolit). Aksi komposit berpengaruh terhadap beban runtuh. Eksperimen dan analisis menunjukkan bahwa retak awal terjadi akibat lentur dan jenis keruntuhan plat adalah geser pons. Analisis ATENA menunjukkan bahwa sebelum baja tulangan leleh, yaitu pada beban 96,64 ton (prototype), kegagalan bidang interface (slip) sudah terjadi, yaitu pada beban 45,56 ton (prototype).

In the bridge deck fabrication, the precast plate concrete is generally used as a framework of cast-in-situ concrete. To increase the efficiency of the structure, the precast plate should be set as a structural element in the composite bridge deck. The objective of this research is to investigate the behavior and strength of the composite bridge deck subjected to static concentrated load. The dimension of the plate model was 1500 mmx725mmx100mm (scale 1:2). The composite plate was build from precast plate with 35 mm depth and cast-in-place plate with 65 mm depth. Both of them were joined by epoxy resin bonding agent (erba) Sikadur-732 for interface shear strengthening, meanwhile in the other group, the precast and cast-in-place concrete were joined without erba. The tire load was modelled as a point-displacement-load at 250mmx100mm area. The ATENA v. 2.1.8 (demo version) program was used to solve the nonlinear finite element formula, and the GID v.7.4.4.b program was used for 3D modelling. The analysis result showed that the Pfirst-crack value of composite plate with ERBA was about 5.18 tons (or 20.72 tons for prototype). The Pfirst-crack value in the analysis was about 33.83% smaller than that in the experiment. The experiment showed that the failure-load of the composite plate with ERBA was 33.26 tons (or 133.04 tons for prototype). The failure-load of composite plate with and without ERBA was 5.18% and 10.24% respectively smaller than that of non-composite plate. The composite-action was influenced the failure load. Both of experiment and analysis showed that the initial crack was caused by flexure, and the failure type of plates was punching shear. The ATENA analysis showed that before the reinforcement of plate yield, i.e. at load 96.64 tons (prototype), the interface failure (slip) was occured i.e, at load 45.56 tons (prototype).

Kata Kunci : Plat Lantai Jembatan,Komposit,Beban Terpusat, precast, cast-in-place, composite, concentrated load, ATENA, GID, interface, first crack, failure load, punching shear, interface failure