ANALISIS KASUS PENURUNAN PONDASI JARINGAN TRANSMISI 150KV KALIMANTAN TIMUR

ABSTRACTElectricity is undeniably a primary need for all human beings in the world after water, land, and air. The more developed a country is, the higher the need for electricity will be. To keep up with the demands, power plants which are built, mostly in rural areas. The generated electricity is then delivered to consumers through transmission networks. A transmission network is needed to deliver the electricity from plants to consumers. Electricity generated by the power plants is channeled through electricity transmission, which is connected by using electric towers. The terrain of the construction of the electric transmission tower is very diverse; and the soil types upon which the towers are built greatly affect the stability of the tower’s foundation. The tower’s foundation should be able to withstand the weight of the transmission networks, so that towers stability should not interfere with electricity distributions process. This study aims to analyze the foundational decline that occurred in the transmission tower in East Kalimantan that was built on peat soil. ABSTRAKListrik tidak dapat dipungkiri sudah menjadi kebutuhan primer bagi seluruh umat manusia di dunia setelah air, tanah, dan udara. Semakin maju sebuah negara maka kebutuhan akan listrik negara tersebut akan semakin tinggi, oleh karena itu negara harus mampu untuk menyediakan kebutuhan listrik itu. Kebutuhan listrik tersebut dapat dipenuhi dengan membangun pembangkit-pembangkit listrik, pada umumnya pembangkit listrik dibangun di daerah pinggiran kota. Ketika pembangkit-pembangkit listrik tersebut yang telah dibangun dan telah menghasilkan listrik maka diperlukan jaringan transmisi listrik untuk menyalurkan listrik yang telah dihasilkan tersebut. Jaringan transmisi listrik tersebut melalui tower-tower listrik. Medan pembangunan tower tower transmisi listrik tersebut sangat beragam, kondisi alam, jenis tanah sangat mempengaruhi dalam pembangunan pondasi tower listrik. Pondasi listrik tersebut harus mampu untuk memikul beban yang akan dibebani pada pondasi dan tidak terjadi kegagalan agar tower transmisi tetap kokoh dan tidak menganggu proses penyaluran transmisi tersebut akibat pondasi yang tidak mampu memikul. Penelitian ini bertujuan untuk menganalisa penurunan yang akan terjadi pada pondasi tower transmisi yang telah dibangun di Kalimantan timur yang mempunyai kondisi tanah gambut dan mengalimi penurunan setelah pondasi selesai dibangun.Kata Kunci: listrik, kebuthan listrik, jaringan transmisi listrik, tower listrik, pondasi, tanah gambut

Response of Groundwater and Soil Displacement at Slope of Electric Transmission Tower Due to Rainfall Events

Climate change is one of the global challenges that give high impact to the environment and societies nowadays. One of the impacts of climate change is slope failure due to fluctuations in rainfall pattern. This paper aims to investigate the response between groundwater, soil displacement to rainfall and rainfall duration. The study was conducted by site observation at three different locations located under a transmission tower at hilly topography area. All parameters are observed hourly by specified instruments installed in the studied slopes. The study found that rainfall does not cause changes to groundwater and cumulative soil displacement increased proportionally to the amount of rainfall. The analysis extended on determining the correlation between displacement to the amount of received rainfall and rainfall duration by the statistical approach and the predictive variability is 91%. The mathematical equation expressed by this study could be used in predicting soil displacement based on rainfall events, the possibility of landslide occurrence or future modelling purposes.

Influence of Ice Covering on Stiffness of Tower Components

In the icing electric transmission tower computation, has neglected the influence of ice stiffness and geometric effect to the iron tower component's stiffness. In the heavy ice area, such simplification is possibly inappropriate. Base on the parallel principle, proposed the ice-coated compression bar flexural stiffness formula, and proofed result correctness through finite element computation. Took the circular solid section and circular tuber section ice-coated tower components for example, ice-coated tower components were equivalent to compound materials in heavy ice area. Under certain load condition, compared the deflection and stiffness of tower component covered the different thickness ice, which took the line load with equivalent to the compound materials. Result showed that in the heavy ice area, the ice geometry effect has increased the tower component stiffness. The influence is more obvious to the tower stiffness than its dead-weight.