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Tanah terserak merupakan tanah bermasalah lantaran sifat semula jadinya yang mudah bertindak balas apabila terdapat kehadiran air lalu meningkatkan potensi hakisan cerun. Kewujudan ion natrium pada mineral lempung tanah melemahkan ikatan elektrokimia tanah terserak menyebabkan zarah lempung menolak dan menjauhi satu sama lain. Faktor ini mendorong pengasingan zarah tanah lalu membentuk fitur hakisan seperti ril dan galur rencam di permukaan bercerun, hakisan paip di dalam sub-permukaan landai dan kewujudan keruping merekah yang menjadi permasalahan dalam pembinaan struktur bangunan serta kejadian bencana alam. Kewujudan mineral lempung berbeza kapasiti pengembangan-pengecutan di kawasan tanah terserak menghasilkan morfologi dan sifat serakan tanah yang berbeza. Oleh itu, objektif kajian ini dijalankan adalah untuk mencirikan sifat fizikal tanah terserak tropika berdasarkan limpahan mineral lempung kaolinit dan montmorilonit serta hubungannya terhadap pembentukan morfologi hakisan cerun dan keruping tanah melalui pemerhatian lapangan dan analisis makmal. Hasil kajian mendapati kadar serakan dipengaruhi oleh sifat fizikal tanah seperti taburan saiz butiran, had cecair (LL), indeks keplastikan (PI), kandungan mineralogi lempung, nisbah % pasir/% zarah halus serta nisbah PI/LL. Analisis makmal menunjukkan tanah terserak dengan kehadiran mineral kaolinit dilihat kurang sensitif terhadap serakan berbanding mineral montmorilonit. Pemerhatian di lapangan mendapati tanah lempung kaolinit berasosiasi dengan pembentukan fitur hakisan ril dan galur rencam di sisi cerun secara lateral dan separa lateral, manakala tanah lempung montmorilonit tidak membentuk fitur hakisan yang nyata namun cenderung membentuk lapisan keruping dengan sistem jaringan rekahan heksagonal pada cerun bersudut hampir tegak (≈80°). Pencirian ini penting bagi meramal kewujudan dan taburan tanah terserak tropika berdasarkan limpahan mineral lempung yang berupaya menjadi pencetus kepada mekanisme geo-bencana yang sinonim berlaku di Malaysia.

Highlights • Development of a novel method to assess environmnetal hazards of industrial, and municipal wastes. • Application of the inverted RES2-D data using the Oasis Montaj to generate a rectangular prism model. • Using the rectangular prism model developed to estimate the volume of IWM and MSW materials. • Quantification of the leachate contaminant plumes flow from IWM and MSW for remediation., A novel methodological approach was developed to quantified the volume of industrial waste desposal (IWD) site, combined with municipal waste materials (MWM), through the integration of a non-invasive, fast, and less expenssive RES2-D Electrical Resistivity Technique (ERT), using Wenner-Schlumberger electrode array geophysical method with Oasis Montaj software. Underground water bearing structures, and the eco-system are being contaminated through seepage of the plumes emanating from the mixtures of the industrial waste materials (IWM), made of moist cemented soil with municipal solid wastes (MSW) dumped at the site. The distribution of the contiminant hazardous plumes emanating from the waste materials' mixtures within the subsurface structural lithological layers was clearly map and delineated within the near-surface structures, using the triplicate technique to collect samples of the soil with the waste mixtures, and the water analysis for the presence of dissolved ions. The deployed method helped to monitor the seepage of the contaminant leachate plumes to the groundwater aquifer units via the ground surface, through the subsurface stratum lithological layers, and hence, estimation of the waste materials' volume was possibly approximated to be 312,000 m3. In summary, the novel method adopted are as presented below:•The novel method is transferable, reproduce-able, and most importantly, it is unambiguous technique for the quantification of environmental, industrial and municipal waste materials.•It helps to map the distribution of the plumes emanating from the waste materials' mixtures within the subsurface structural lithological layers that was clearly delineated within the near-surface structures underlain the study site.•The procedure helped in the monitoring of leachate contaminants plumes seepages into the surface water bodies and the groundwater aquifer units, via the ground surface, through to the porous subsurface stratum lithological layers., Graphical abstract Image, graphical abstract

Industrial, and municipal wastes are part of the main sources of environmental hazards as well as groundwater and surface water pollutions. If not well composed, treated, and safely disposed, it could permeate through the subsurface lithologies by reaching down to the underground water aquifers, particularly in zones of unprotected aquifer units. Pollutants, most especially the landfills leachates that encompassed organic contaminants, ammonia, nitrates, total nitrogen, suspended solids, heavy metals and soluble inorganic salts, i.e., soluble nitrogen, sulphur compound, sulphate and chlorides, could posed undesirable environmental impacts due to inappropriate disposals that may give rise to gaseous fumes and leachate formations. An electrical resistivity geophysical technique utilizing the RES2D no-invasive, cost-effective and rapid method of data collection was integrated with the 3D Oasis Montaj software to approximate the volume of the generated rectangular prism model of the contaminants delineated from mixtures of the industrial, and municipal wastes plumes to be 312,000 m 3.

Tanah runtuh jenis rayapan merupakan salah satu fenomena geobencana yang sering terjadi dalam skala yang besar dan amat berkait rapat dengan perubahan tekanan air liang. Ia bercirikan canggaan jangka masa panjang maka dengan itu pengetahuan mendalam terhadap tindak balas rayapan di dalam keadaan tepu dan tidak tepu air adalah penting untuk meramal pergerakan masa hadapan. Kertas ini bertujuan mengkaji tindak balas rayapan di dalam sampel lempung bebola menggunakan kotak ricih terus yang terubah suai. Simulasi rayapan dibuat menggunakan model analog mekanik hasil gabungan spring dan peredam. Parameter γo (pergerakan rayapan awal) yang diperoleh daripada ujian kotak ricih terubah suai digunakan sebagai input parameter bersama-sama dengan parameter lain yang diperoleh berdasarkan kaedah kuasa dua terkecil. Simulasi oleh model analog mekanik terhadap tindak balas rayapan yang direkod di makmal berjaya merakam tindak balas rayapan awal dan akhir. Keputusan kajian mendapati bahawa tindak balas rayapan adalah lebih signifikan di dalam keadaan tepu air berbanding keadaan tidak tepu air.

Environmental hazards, industrial, and municipal wastes geochemical and geophysical assessments were carried out at an industrial waste disposal (IWD) site at Bukit Kepong, Kuala Lumpur, Malaysia. RES2-D geophysical method was applied, capable of identification and quantification of the industrial wastes; buried hazardous materials (BHM) and their effects on the subsurface stratum, from the moderately saturated zones, to fully saturated zones housing the aquifer units underneath the water table. Six RES2-D survey profiles were respectively acquired along E-W, and N-S directions. The perpendicular arrangement of the RES2-D survey lines, was tenaciously designed to make possible, the industrial waste materials (IWM)and municipal solid waste (MSW) quantification, with sufficient length of survey lines set at 200 m, and electrode spacing of 5 m, to cover as much details segments of the IWM and MSW as possible. The six RES2-D inversion results, helped in the subsurface stratum classification into three layers, namely; soft layers, which encompasses the waste materials, with varied resistivity values i.e., 0–100 Ω-m, at 10–15 m depths. The consolidated layers produced varied resistivity values i.e., 101–400 Ω-m, at 15–20 m depths. The bedrock has the highest resistivity values i.e., 401–2000 Ω-m, at depths > 20 m. The estimated volume of the waste materials was 312,000 m 3, using 3-D Oasis Montaj modeling via rectangular prism model generated from the inverted RES2-D. Results from the geochemical analysis helped in the validation of the site as a potential contaminated zone with severe health effects.

Translational slides in clays are often characterized by long-lasting intermittent movements associated with the fluctuations of pore-water pressure. Physically-based models designed to support hazard analysis of landslide movements and early warning systems require the integration of time-dependent (viscous) constitutive models for the shear displacements because landslide movements are typically controlled by the viscous behaviour of the clay geo-material. This paper presents an investigation of the viscous response of a clay geo-material under saturated and unsaturated conditions. Creep and relaxation tests have been first carried out on saturated clay samples by means of direct shear box. To gain a conceptual understanding of the viscous response of the clay in shear, mechanical analogues were considered based on combinations of springs and dashpots. Preliminary tests on unsaturated samples were finally carried out to gain a first insight into the viscous response of the clay under unsaturated conditions.