Cement Treated Base (CTB) is a pavement layer located between the sub-base and surface layers. This pavement layer uses fine aggregate (sand) and cement as a binder. Fly ash is coal burning waste that can be used as an added material for road pavement. This study aimed to analyze the use of fly ash in the cement treated base pavement mixture. Fly ash was used as a substitute of cement. The composition used consists of fine aggregate (sand), cement, fly ash and water. The compressive strength test was carried out on variations in the composition of the test object. The requirements for CTB specifications were to have compressive strength test results ranging between 45 kg/cm2 – 55 kg/cm2 at the age of the test object for 7 days. After being tested, it was found that the composition of 70% fine aggregate (sand), 5% Portland cement, and 25% fly ash had an average compressive strength of 49.823 kg/cm2.

Peningkatan jumlah penduduk dan jumlah kendaraan dapat menimbulkan permasalahan baru dalam berlalu lintas, seperti kebutuhan struktur jalan yang lebih baik, meningkatnya pelanggaran lalu lintas dan risiko kecelakaan lalu lintas. Tujuan dari penelitian ini adalah untuk menganalisis daerah rawan kecelakaan pada ruas jalan Ahmad Yani Km 37 – Km 82 Kabupaten Banjar. Metode yang digunakan untuk mengidentifikasi daerah rawan kecelakaan adalah dengan menghitung Tingkat Kefatalan (TF) dan UCL (Upper Control Limit). Dari hasil analisis data, terdapat 14 ruas jalan yang teridentifikasi sebagai daerah rawan kecelakaan (blacksite) dan yang memiliki tingkat nilai TF tertinggi di Jl. A. Yani km 63 – Jl. A. Yani km 64, yaitu TF = 137.342 dan nilai UCL = 76.464. Selain itu, didapatkan 44 titik ruas jalan yang teridentifikasi sebagai Blackspot. Titik ruas jalan yang memiliki nilai TF tertinggi adalah titik Jl. A. Yani km 47- km 47,25 yaitu TF = 457.808 dan nilai UCL = 93.720. Rekomendasi untuk mengurangi tingkat kecelakaan lalu lintas yang dianjurkan yaitu dengan memasang rambu-rambu lalu lintas, lampu penerangan jalan, guardrail untuk tikungan serta sosialisasi keselamatan berkendara.

The more coal production is produced, the more waste is coming from the combustion process which leads to the environmental pollution. Waste from burning coal in the form of fly ash can be used as a mixture of subgrade stability in highway construction. The purpose of this study is to determine the characteristic value of each combination of fly ash, Liang Anggang sand and cement as a mixture of subgrade layer materials. The test objects consist of 10 combinations of fly ash, Liang Anggang sand and cement. Some tests were conducted such as Atterberg Limits, Specific Gravity, Sieve Analysis, Compaction and CBR test, respectively. From all combinations of the test objects, the best combination that suits the characteristic values of a subgrade layer mixture is a combination of minimum 6% of CBR specification and a maximum of 6% of Plasticity Index (PI). The recommended economical combination for landfill soil is a combination of test objects with a composition of 75% fly ash, 20% Liang Anggang sand and 5% cements.