Pengaruh Pemodelan Zona Terkekang Terhadap Prediksi Hubungan Momen-Kurvatur Kolom Persegi Beton Mutu Tinggi

Authors

  • Iswandi Imran Staf Pengajar Departemen Teknik Sipil, FTSP-ITB.
  • Remigildus Cornelis Mahasiswa Program Magister Teknik Sipil, FTSP-ITB.

DOI:

https://doi.org/10.5614/jts.2005.12.2.3

Keywords:

Kolom persegi beton mutu tinggi, Model daerah terkekang, Hubungan momen-kurvatur, Kekuatan, Daktilitas.

Abstract

Abstrak. Paper ini mengkaji salah satu aspek yang berkaitan dengan pemodelan daerah terkekang pada kolom persegi beton mutu tinggi yang diberi beban aksial tekan eksentrik. Cakupan daerah terkekang pada penampang kolom adalah parameter yang dikaji untuk melihat pengaruhnya terhadap prediksi analitis kekuatan dan daktilitas kolom. Beberapa pemodelan daerah terkekang yang sering digunakan dalam berbagai literature dievaluasi untuk mengetahui karakteristik dan sensitivitasnya. Selanjutnya dalam paper ini dikembangkan program komputer MOKUR2D untuk menganalisis hubungan momen-kurvatur kolom persegi beton mutu tinggi. Dalam program, cakupan daerah terkekang pada penampang kolom dapat dimodelkan dengan tiga pendekatan, yaitu pendekatan model konvensional yang menggunakan koefisien kekangan efektif, model dengan daerah arching action yang tak terkekang dan model penampang dengan tiga variasi derajat kekangan yang berbeda. Studi perbandingan dengan menggunakan program tersebut kemudian dilakukan terhadap 4 buah kolom yang diuji oleh Sheikh dan Bayrak [1998]. Semua kolom tersebut berdimensi 305 x 305 mm, dengan delapan tulangan longitudinal berdiameter 19.5 mm yang terdistribusi merata pada penampang. Tegangan leleh tulangan baja yang digunakan adalah 454 MPa. Dua tipe konfigurasi sengkang yang dikaji masing-masing adalah sengkang diamond dan konvensional dengan volumetric ratio berkisar antara 1.68 hingga 5.24 persen. Spasi tulangan sengkang yang terpasang berkisar antara 90 mm hingga 108 mm. Hasil analisis menunjukkan bahwa pemodelan daerah terkekang dengan model konvensional masih cukup akurat walaupun sedikit overestimate terhadap hasil eksperimen sedangkan model dengan tiga variasi derajat kekangan terlihat memiliki akurasi respon teoritis momen kurvatur yang lebih baik dan sangat mendekati hasil eksperimen jika kekangan pada daerah arching action ditetapkan sebesar 50% dari kekangan pada inti kolom.

Abstract. This paper studies one aspect of confinement modeling of high strength concrete square columns subjected to axially eccentric compression. Confined zone models were studied to evaluate their effect on the analytical prediction of strength and ductility of high strength concrete square columns. Several models of confined zones found in literatures were discussed to observe their characteristics and sensitivity. Based on the findings, a computer program MOKUR2D was developed. In the program, confined zone in reinforced concrete columns can be modeled with three different approaches, i.e. conventional models (using a coefficient of effective confinement), models with unconfined arching zone, or models with three zones of confinement. A comparative study using the program was later carried out on 4 high-strength concrete square columns tested by Sheikh and Bayrak [1998]. The cross-section size of all columns was 305 x 305 mm. All columns were reinforced with 8 bars of 19.5 mm diameter, uniformly distributed around the core perimeter. Yield strength of the rebars was 454 MPa. Two types of ties configuration ties were used with volumetric ratio varying from 1.68 percent to 5.12 percent. The spacing of the ties was from 90 mm to 108 mm. From the study, it was found that the conventional model is able to produce a fairly good estimate of test results. The best estimate of test results is given by the model with three zones of confinement in which the arching zone
is assigned with 50% of full confinement.

References

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Published

2010-05-01

How to Cite

Imran, I., & Cornelis, R. (2010). Pengaruh Pemodelan Zona Terkekang Terhadap Prediksi Hubungan Momen-Kurvatur Kolom Persegi Beton Mutu Tinggi. Jurnal Teknik Sipil, 12(2), 75-86. https://doi.org/10.5614/jts.2005.12.2.3

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