Abstract :
Identifikasi jenis tanah ekspansif diperlukan sebagai upaya pencegahan
atau mitigasi dalam perencanaan pembangunan. Lokasi penelitian berada di
Perumahan ?X? Kecamatan Alam Barajo Kota Jambi termasuk ke dalam Formasi
Muaraenim. Penelitian ini menggunakan metode geolistrik konfigurasi Wenner-
Schlumberger sebanyak 4 lintasan dengan Panjang lintasan 150 meter dengan
spasi jarak antar elektroda 10 meter. Dan uji struktur tanah, yang meliputi uji
analisis butiran dan batas-batas Atterberg. Hasil pemodelan struktur bawah
permukaan, nilai resistivitas antara 5,68 ? 52,6 ?m yang diduga sebagai lempung
terdapat di tiga zona daerah penelitian. Zona pertama terletak di arah barat laut,
zona kedua terletak di arah timur laut dan zona ketiga terletak di arah selatan,
didukung pengujian sifat fisik dan jenis tanah dari keempat titik sampel tanah di
Perumahan ?X?, hasil uji batas Atterberg maupun uji analisis butiran saling
mendukung dan diidentifikasi jenis tanah di Perumahan ?X? didominasi oleh
pasir pada sampel 1, 2, dan 4. Pada sampel 3, yang merupakan didominasi oleh
lempung, ini dapat dijadikan perhatian khusus karena memiliki nilai plastisitas
sedang dan tanah kohesif, yang berakibat tanah mudah mengembang dan mudah
menyusut akibat perubahan kadar air.
Kata kunci : tanah ekspansif, metode geolistrik, dan wenner-schlumberger
Identification of expansive soil types is needed as a prevention or mitigation
effort in development planning. The research location is in Housing "X" Alam Barajo
District, Jambi City, which is included in the Muaraenim Formation. This study used
the Wenner-Schlumberger geoelectric method with 4 paths with a track length of
150 meters and a spacing of 10 meters between electrodes. And soil structure tests,
which include grain analysis tests and Atterberg limits. The results of modeling the
subsurface structure, resistivity values between 5.68 ? 52.6 ?m which are
suspected to be clay in the three zones of the study area. The first zone is located
in the northwest, the second zone is located in the northeast and the third zone is
located in the south, supported by tests of physical properties and soil types from
the four soil sample points in Housing "X", the results of the Atterberg boundary test
and grain analysis tests are mutually exclusive. support and identify the type of
soil in Housing "X" which is dominated by sand in samples 1, 2 and 4. In sample 3,
which is dominated by clay, this can be of particular concern because it has a
moderate plasticity value and is cohesive soil, which results in easy soil expands
and shrinks easily due to changes in moisture content.
Keywords : expansive soil, geoelectric method, and wenner-schlumberger