Analisis Peningkatan Faktor Keamanan Lereng Pada Areal Bekas Tambang Pasir Dan Batu di Desa Ngablak, Kecamatan Cluwak, Kabupaten Pati

Abstract

Management of post mining land become serious concern for government in current time. Post miningarea that located in Ngablak village, Cluwak districts of Pati is one of post mining areas that did notmanaged and creates problems to civilian and village government, for example are safety andenvironment problems. Safety of environment disturbed because of mining activities that finished andcreated unstable slope (potentially landslide) caused by land dredging. To solve this problems,government need to make some research about stability of slope and studies about method ofanalysis which can increase the safety factor of slope. Slope stability analysis can be done with Side6.0 software which needs laboratory result data of soil mechanics. Methods that can increase slope’ssafety factor can be installation of retaining wall and cut and fill method that make the slope becometerraces. Efficiency of method that will be selected, can be tested by using Slide 6.0 software.Installation of retaining wall could increase the safety factor’s value become 1.103, this valuerepresents that the slope is still potentially to be landslide. However, cut and fill can increases safetyfactor’s value become 1.330, that representing slope condition is stable and safe.

Numerical Modeling of Claystone Slope Stability (Case Study of the Sumedang-Cirebon Road Section Km 68+750)

“…Penyebab lain adalah sifat tanah yang mengandung mineral yang mampu kembang susut seperti lempung dan lanau yang sering kali dalam keadaan retak-retak atau bercelah, sehingga tekanan air pori dapat membahayakan stabilitasnya. Selain itu bisa diakibatkan oleh pengaruh tipe perlapisan khusus misalnya antara pasir dan lempung, tekanan beban yang berlebihan pada kepala lereng atau pemotongan kaki lereng dan dalam beberapa kasus struktur tanah umumnya diperlemah oleh proses fisika dan kimia (Khrisna et al, 2013) Stabilitas lereng atau kemampuan lereng menahan terjadinya longsoran ditunjukan dengan nilai faktor keamanan (FK) yaitu perbandingan antara gayagaya yang menahan, terhadap gaya-gaya yang menggerakkan tanah tersebut (Ali et al, 2017). Agar lereng menjadi stabil maka gaya-gaya yang mengakibatkan longsor haruslah lebih kecil dari pada gaya-gaya yang ada sehingga faktor keamanan akan menjadi lebih besar atau sama dengan satu (Pangemanan et al, 2014).…”