Evaluasi Struktur Gedung X di Jakarta Berdasarkan Sni 03-1726-2012 Ketahanan Gempa untuk Struktur Gedung

Wilayah Jakarta berada pada zonasi gempa menengah berdasarkan peta zonasi gempa 2010 yang dipublikasikan oleh Pusat Penelitian dan Pengembangan Pemukiman (PUSKIM), Kementrian Pekerjaan Umum. Tujuan penelitian ini adalah merekomendasikan perkuatan struktur pada eksisting gedung X di Jakarta, agar ketika gempa datang, struktur gedung tersebut tetap mampu memikul beban ultimit. Objek penelitian merupakan gedung kategori high rise building, memiliki jumlah lantai lebih dari 10, dibangun sebelum tahun 2010, berlokasi pada kelas situs tanah lunak dan secara visual terindikasi adanya kerusakan pada elemen struktur. Pemodelan struktur gedung X didesain dan dianalisis menggunakan program ETABS. Pembebanan gempa diberikan secara dinamik menggunakan prosedur analisis spektrum respons ragam. Hasil analisis story drift menunjukan bahwa gedung X dinyatakan aman terhadap kinerja batas ultimit yang telah dihitung berdasarkan pedoman gempa SNI 03-1726-2012. Nilai maksimum simpangan antar lantai pada gedung X untuk arah-x sebesar 68,60 mm dan arah-y sebesar 101,2 mm. Bagaimanapun, hasil analisis struktur pemodelan gedung X pada ETABS menunjukkan bahwa terdapat beberapa elemen balok dan kolom yang membutuhkan perkuatan struktur. Perkuatan elemen balok direncanakan menggunakan CFRP yang dihitung keamanannya berdasarkan pedoman ACI 440.2R-8 Perkuatan elemen kolom direncanakan menggunakan Concrete Jacketing yang dianalisis melalui section designer pada program ETABS dan dihitung keamanannya berdasarkan pedoman SNI 03-2847-2013

Insights into the chemical composition of Equisetum hyemale by high resolution Raman imaging

Equisetaceae has been of research interest for decades, as it is one of the oldest living plant families, and also due to its high accumulation of silica up to 25% dry wt. Aspects of silica deposition, its association with other biomolecules, as well as the chemical composition of the outer strengthening tissue still remain unclear. These questions were addressed by using high resolution (<1 μm) Confocal Raman microscopy. Two-dimensional spectral maps were acquired on cross sections of Equisetum hyemale and Raman images calculated by integrating over the intensity of characteristic spectral regions. This enabled direct visualization of differences in chemical composition and extraction of average spectra from defined regions for detailed analyses, including principal component analysis (PCA) and basis analysis (partial least square fit based on model spectra). Accumulation of silica was imaged in the knobs and in a thin layer below the cuticula. In the spectrum extracted from the knob region as main contributions, a broad band below 500 cm−1 attributed to amorphous silica, and a band at 976 cm−1 assigned to silanol groups, were found. From this, we concluded that these protrusions were almost pure amorphous, hydrated silica. No silanol group vibration was detected in the silicified epidermal layer below and association with pectin and hemicelluloses indicated. Pectin and hemicelluloses (glucomannan) were found in high levels in the epidermal layer and in a clearly distinguished outer part of the hypodermal sterome fibers. The inner part of the two-layered cells revealed as almost pure cellulose, oriented parallel along the fiber

Study on the Soil Strength and Density Relationships of Latosol and Red Yellow Podzolic Soils

The soil strength characteristic, which is usually e.xpressed bycohesion and internal piction, is as basic data for applying farmmachineries/equipments and farm structures. The objective of this research is to study the soil strength and density relationships of latosol and red yellowish podzolic soil. This research was conducted by standard compaction test and soil strength test (uniaxial, direct shear and triaxiul)

Study on the Soil Strength and Density Relationships of Latosol and Red Yellow Podzolic Soils

The soil strength characteristic, which is usually e.xpressed bycohesion and internal piction, is as basic data for applying farmmachineries/equipments and farm structures. The objective of this research is to study the soil strength and density relationships of latosol and red yellowish podzolic soil. This research was conducted by standard compaction test and soil strength test (uniaxial, direct shear and triaxiul)