Hydromechanics – Slope Monitoring in Rainy Season


  • Agus Setyo Muntohar Universitas Muhammadiyah Yogyakarta
  • Ani Hairani Universitas Muhammadiyah Yogyakarta
  • Muhammad Fikri Permana Universitas Muhammadiyah Yogyakarta
  • Farid Nur Bahti Universitas Muhammadiyah Yogyakarta




suction, soil moisture content, rainfall, infiltration, slope monitoring


Rainfall and soil response are necessary to be monitored to have slope characteristics in detecting landslide occurrence. Even though much research has been carried out worldwide for rainfall monitoring, less research has been conducted in Indonesia for slope monitoring. Therefore, this research was conducted to observe the suction, soil moisture content, and rainfall in a silty sand slope. An automatic rain gauge was set on the ground to measure precipitation. Tensiometer and soil moisture content sensors were installed at depths of 0.5 m; 1 m; and 1.5 m from the slope surface. The monitoring was conducted during the peak rainy season from December 2022 to January 2023. The rainfall amount is about 436.6 mm, and the 6 hours of rainfall events contribute a relatively sizeable rainfall amount (about 31%) to the total. The safety factor of the slope is estimated to decrease by 39%-40% due to the rainfall.


Guo, H., Understanding Global Natural Disasters and the Role of Earth Observation, International Journal of Digital Earth, 3(3), 2010, pp. 221-230.

Cruden, D.M., A Simple Definition of a Land¬slide, Bulletin of the International Association of Engineering Geology, 43(1), 1991, pp. 27-29.

Wieczorek, G.F., Preparing a Detailed Landslide-Inventory Map for Hazard Evaluation and Reduction, Bulletin of the Association of Engineering Geologists, 21(3), 1984, pp. 337-342.

Angeli, M.G., Pasuto, A., and Silvano, S., A Critical Review of Landslide Monitoring Experiences, Engineering Geology, 55, 2000, pp. 133–147, doi: 10.1016/S0013-7952(99)00122-2.

Chae, B.G., Park, H.J., Catani, F., Simoni, A., and Berti, M., Landslide Prediction, Monitoring and Early Warning: a Concise Review of State-of-the-Art, Geosciences Journal, 21(6), 2017, pp. 1033-1070, doi: 10.1007/s12303-017-0034-4.

Toll, D., Lourenço, S., Mendes, J., Gallipoli, D., Evans, F., Augarde, C., Cui, Y.J., Tang, A. M., Rojas, J., and Pagano, L., Soil Suction Monitoring for Landslides and Slopes, Quarterly Journal of Engineering Geology and Hydrogeology, 44, 2011, pp. 23 - 33, doi: 10.1144/1470-9236/09-010.

Kim, K.S., Jeong, S.W., Song, Y.S., Kim, M., and Park, J.-Y., Four-Year Monitoring Study of Shallow Landslide Hazards based on Hydrological Measurements in a Weathered Granite Soil Slope in South Korea, Water, 13(17), 2021, doi: 10.3390/w13172330.

Muntohar, A.S., Fata, N., Jotisankasa, A., and Yang, K.H., Suction Monitoring and Stability of Volcanic-Residual Soil Slope During Rainfall, Civil Engineering Dimension, 22(2), 2020, pp. 68-74, doi: 10.9744/CED.22.2.68-74.

[Tohari, A., Variations of Pore-Water Pressure Responses in a Volcanic Soil Slope to Rainfall Infiltration, Jurnal RISET Geologi dan Pertam-bangan, 23(2), 2013, doi: 10.14203/risetgeotam 2013.v23.73.

Liu, G., Zha, X.Y., Guan, J.K., and Tong, F.G., Field Experiment of Rainfall Infiltration on a Soil Slope and Simulations Based on a Water-Air Two-Phase Flow Model, Journal of Mountain Science, 18(8), 2021, pp. 2159-2167, doi: 10.1007/ s11629-020-6322-x.

Aleotti, P., A Warning System for Rainfall-induced Shallow Failures, Engineering Geology, 73(3-4), 2004, pp. 247-265, doi: 10.1016/j.enggeo. 2004.01.007.

Caine, N., The Rainfall Intensity-duration Control of Shallow Landslides and Debris Flows, Geografiska Annaler: Series A, Physical Geography, 62(1-2), 1980, pp. 23-27.

Muntohar, A.S. and Soebowo, E., Stability Analysis of A Shallow Slope Failure During Rainy Season in Kulonprogo, Indonesia, in International Conference on Landslides and Slope Stability (SLOPE 2015), Bali, Indonesia, P.P. Rahardjo and A. Tohari, Eds., 27-30 September 2015 2015: Parahyangan Catholic University, pp. F5.1-F5.8.

BMKG, Forecasting of the Onset of Rainy Season in 2022/2023, Meteorology, Climatology, and Geophysical Agency (in Bahasa Indonesia), Jakar-ta, 2022.

Guzzetti, F., Peruccacci, S., Rossi, M., and Stark, C.P., Rainfall Thresholds for the Initiation of Landslides in Central and Southern Europe, Meteorology and Atmospheric Physics, 98, 2007, pp. 239–267, doi: 10.1007/s00703-007-0262-7.

Muntohar, A.S., Hairani, A., Nabila, K.A., and Agrina, N., Potensi Penggunaan Intensitas Hujan Hasil Pengamatan Satelit untuk Ambang Hujan Pemicu Tanah Longsor, Jurnal Teknik Sipil, 17(1), 2022, pp. 12–17, doi: 10.24002/jts. v17i1.6125.

Muntohar, A.S. and Liao, H.J., Factors Affecting Rain Infiltration on a Slope Using Green-Ampt Model, Journal of Physical Science, 30(3), 2019, pp. 71–86, doi: 10.21315/jps2019.30.3.5.

Xue, J. and Gavin, K., Effect of Rainfall Intensity on Infiltration into Partly Saturated Slopes, Geotechnical and Geological Engineering, 26(2), 2007, pp. 199-209, doi: 10.1007/s10706-007-9157-0.

Holtz, R.D., Kovacs, W.D., and Sheahan, T.C., An Introduction to Geotechnical Engineering, Pearson, New York, 2011.

Dairaku, K., Kuraji, K., Suzuki, M., Tangtham, N., Jirasuktaveekul, W., and Punyatrong, K., The Effect of Rainfall Duration and Intensity on Orographic Rainfall Enhancement in a Mountainous Area: A Case Study in the Mae Chaem watershed, Thailand, Journal of Japan Society of Hydrology and Water Resources, 13, 2000, pp. 57-68, doi: 10.3178/jjshwr.13.57.

Kuraji, K., Punyatrong, K., and Suzuki, M., Altitudinal Increase in Rainfall in the Mae Chaem Watershed, Thailand, Journal of the Meteorological Society of Japan, 79(1B), 2001, pp. 353-363, doi: 10.2151/jmsj.79.353.

Dairaku, K., Emori, S., and Oki, T., Rainfall Amount, Intensity, Duration, and Frequency Relationships in the Mae Chaem Watershed in Southeast Asia, Journal of Hydrometeorology, 5(3), 2004, pp. 458–470, doi: 10.1175/1525-7541 (2004)005<0458:raidaf>2.0.co;2.

WMO, Technical Regulations (WMO-No. 49) Volume III Hydrology, Publications Board World Meteorological Organization, Geneva, Switzerland, 2021, p. 40.

Keefer, D.K., Wilson, R.C., Mark, R.K., Brabb, E.E., Iii, W.M.B., Ellen, S.D., Har, E.L., Wieczorek, G.F., Alger, C.S., and Zatkin, R.S., Real-Time Landslide Warning During Heavy Rainfall, Science, 238(4829), 1987, pp. 921-925, doi: 10.1126/science.238.4829.921.

Liu, G., Tong, F., Tian, B., and Tian, W., Influence of Atmospheric Temperature on Shallow Slope Stability, Environmental Earth Sciences, 78(632), 2019, pp. 1-9, doi: 10.1007/s12665-019-8649-6.

Genuchten, M. T. V., A Closed‐form Equation for Predicting the Hydraulic Conductivity of Unsaturated Soils, Soil Science Society of America Journal, 44(5), 1980, pp. 892-898, doi: 10.2136/sssaj1980.03615995004400050002x.

Hamdany, A.H., Shen, Y., Satyanaga, A., Rahardjo, H., Lee, T.T.D., and Nong, X., Field Instrumentation for Realtime Measurement of Soil-water Characteristic Curve, International Soil and Water Conservation Research, 10(4), 2022, pp. 586-596, doi: 10.1016/j.iswcr.2022.01.007.

Tu, X., Kwong, A., Dai, F., Tham, L., and Min, H., Field Monitoring of Rainfall Infiltration in a Loess Slope and Analysis of Failure Mechanism of Rainfall-induced Landslides, Engineering Geology, 105(1-2), 2009, pp. 134-150.

Rahardjo, H., Lee, T.T., Leong, E.C., and Rezaur, R.B., Response of a Residual Soil Slope to Rainfall, Canadiann Geotechnical Journal, 42, 2005, pp. 340-351, doi: 10.1139/T04-101.

Bishop, A.W. and Blight, G., Some Aspects of Effective Stress in Saturated and Partly Saturated Soils, Geotechnique, 13(3), 1963, pp. 177-197.

Li, A., Yue, Z., Tham, L., Lee, C., and Law, K., Field-Monitored Variations of Soil Moisture and Matric Suction in a Saprolite Slope, Canadian Geotechnical Journal, 42(1), 2005, pp. 13-26.

Jotisankasa, A., Mahannopkul, K., and Sawang-suriya, A., Slope Stability and Pore-Water Pressure Regime in Response to Rainfall: A Case Study of Granitic Fill Slope in Northern Thailand, Geotechnical Engineering Journal of the SEAGS & AGSSEA, 46(1), 2015, pp. 45-54.




How to Cite

Muntohar, A. S., Hairani, A., Permana, M. F. ., & Bahti, F. N. (2023). Hydromechanics – Slope Monitoring in Rainy Season. Civil Engineering Dimension, 25(2), 135-142. https://doi.org/10.9744/ced.25.2.135-142