PERBAIKAN TANAH PROBLEMATIK LEMPUNG LUNAK DENGAN METODE STABILISASI KIMIAWI DITINJAU DARI NILAI KADAR AIR DAN INDEKS PLASTISITAS

Soft clay soils generally have unfavorable characteristics or properties, when used as a basis for a construction. The characteristics of soft clay soil are having high soil compressibility, low carrying capacity, low permeability value, being cohesive and having a high level of soil activity. One form of effort to improve the characteristics of the soil's bad properties is to carry out stabilization. Stabilization is an activity of mixing soil with certain materials, and is expected to react with the soil, so that the soil characteristics become better. The methodology applied in this study is chemical stabilization, with mineral materials in the form of marble ash waste with 4 different types of variants. Based on the test results, there was a decrease in the value of the water content and soil plasticity index (PI) of 44.94% in variant 3 (20% marble ash waste) compared to the original soil. It is estimated that there is a reaction from the marble ash on soft clay soil, namely in the form of absorption of excess water contained in the soil and voids contained in the soil filled with marble waste, so that the adhesion between particles becomes better

Pelayanan Baca Tulis Al-Qur’an Untuk Taman Pendidika Al-Qur’an (TPA) At-Taqwa Muhammadiyah Enrekang Untuk Meningkatkan Pendidikan Karakter Bagi Anak (TPA) At-Taqwa Muhammadiyah Enrekang

Artikel ini mendeskripsikan untuk memberikan pelayanan kepada Santri Taman Pendidikan Al-Qur’an (TPA) At-Taqwa Muhammadiyah Enrekang dalam menumbuhkan karakter sejak dini dengan tujuan agar mampu memahami dan mengamalkan Al-Qur’an serta memiliki akhlakul karimah. Metode pelayanan yang digunakan dalam penulisan artikel ini dengan metode Behavior. Peneliti melakukan kajian dengan bersentuhan langsung dengan santriwan/santriwati yang ada di TPA At-Taqwa Muhammadiyah Enrekang. Hasil dari pelatihan ini menunjukkan bahwa dari 6 peran TPA sudah bisa dikatakan berperan baik dalam pendidikan karakter yang dicanangkan oleh Kementerian Pendidikan Nasional yaitu (1) Peran TPA dalam membantu santri mengagumi dan mncintai Al-Qur’an sebagai bacaan yang istimewa (religius), (2) Peran TPA dalam membimbing santri membaca al- qur’an dengan baik dan benar (gemar membaca), (3) Peran TPA dalam mengajarkan sholat 5 waktu dengan tata cara yang benar (disiplin), (4) Peran TPA dalam membina santri menguasai hafalan sejumlah surat pendek atau ayat pilihan dan do’a sehari-hari (mandiri), (5) Peran TPA dalam mengarahkan berakhlak sosial yang baik sesuai dengan tuntunan Islam (peduli sosial), (6) Peran TPA dalam membantu santri menulis huruf Arab dengan baik dan benar (kreatif)

Postseismic coastal development in Aceh, Indonesia: Field observations and numerical modeling

We model postseismic changes to the shoreline of West Aceh, Indonesia, a region largely affected by the December 2004 Sumatra-Andaman earthquake and ensuing Indian Ocean tsunami, using a cross-shore morphodynamic model. Subsidence of 0.5–1.0 m and tsunami scouring during the 2004 event caused the complete destruction of the beach and the landward displacement of the western coast of Aceh by an average of 110 m. Comparing a series of satellite images and topographic surveys, we reconstruct the build-up of a new beach ridge along a 6 km long stretch of coastline in the years following the event. We then use the cross-shore model UNIBEST-TC developed for a wave-dominated sandy shoreline to determine the controlling factors of shoreline recovery. Input parameters include bathymetric data measured in 2015, grain size characteristics of offshore sediment samples, modeled wave data, tidal elevations from a nearby tide-gauge station as well as measured and modeled postseismic uplift data. After establishing a cross-shore profile in equilibrium with the prevailing hydrodynamic conditions, we simulate the post-tsunami recovery, the effect of the monsoon seasons, as well as the influence of postseismic land level changes for up to 10 years and compare them to the observed coastal development. Our modeling results indicate that the recovery of the western Acehnese shoreline after the 2004 tsunami was quick with littoral sediment transport normalizing to pre-tsunami conditions within two to four years following the event. However, field data shows that the shoreline stabilized 50–90 m landward of its pre-2004 tsunami position, most likely due to the build-up of a prominent higher beach ridge in response to coseismic subsidence. Observed variability in shoreline position in the order of a few tens of meters since 2009 can be attributed to seasonal wave climate variability related to the monsoon cycle. The effect of postseismic uplift on shoreline position is small and in the order of only a few meters over 10 years, which is 3 to 5 times smaller than long-term coastal progradation rates that are driven by abundant sediment supply to the littoral zone. This overall progradational trend will promote preservation of seismically modified beach ridges, which can serve as paleoseismic indicators.Applied Geolog