Masa kini, ruang bawah tanah telah menjadi bahagain penting di dalam kemajuan manusia yang melibatkan ekonomi, sosial dan keperluan. Sesetengah kawasan yang membangun amat memerlukan penyelesaian yang lebih baik untuk sistem pengangkutan yang effisien. Terowong cetek biasanya dibina di bawah jalanraya yang sedia ada dan di bawah kawasan yang mempunyai ruang yang terhad. Dalam kajian ini, penyokong atap paip telah dikaji untuk mendapatkan fungsi optimum sistem tersebut yang bertindak sebagai penyokong sementara bagi membolehkan kerja penggalian terowong dijalankan dengan selamat. Atap paip penyokong tersebut dibina dengan memasang serta menyusun beberapa cerucuk konkrit di bahagian atas terowong dengan menggunakan mesin penggali terowong mikro (MTBM). Analisis tersebut telah dijalankan dalam beberapa kes yang berasingan dengna menggunakan model 2D-Finite Element. Model-model tersebut telah dibandingkan berdasarkan tiga bentuk terowong iaitu bulat, ladam kuda, dan empat segi sama. Setiap bentuk terowong telah menjalani beberapa analisa seperti kesan penggunaan penyokong atap pain terhadap kedalaman (0.0d, 0.5d, 1.0d and 2.0d) dan jarak di antara dua terowong berkembar (0.0d, 0.5d, 1.0d and 2.0d). Bahagian terakhir analisa adalah mengenai pembuktian magnitud mendapan hasil ke atas projek yang menggunakan system penyokong atap paip di Padang Rengas, Perak. Berdasarkan analisis yang telah dijalankan, keputusan menunjukkan bahawa mendapan telah berkurang sehingga 90% dengan pemasangan atap paip penyokong tersebut. Magnitud mendapan telah berkurang sehingga 60% apabila kedalaman
terowong ditingkatkan. Bagi terowong berkembar, mendapan telah bertambah daripada sehingga 70% di terowong kedua kesan daripada penggalian yang dilakukan di terowong yang pertama yang menyebabkan gangguan terhadap kekuatan tanah. __________________________________________________________________________________
Nowadays, underground space has become an important part of human development involving economics, social and needs. Some areas especially in the urbanized surroundings are in need of a better solution for an efficient transportation system. Shallow tunnel usually constructed beneath an existing highway or an area with limited spaces to improve transportation network. In the present study, pipe roof support was analyzed to determine the optimum function of its system that acts as a temporary support. The pipe roof is formed by installing a number of horizontal concrete piles at the crown of the tunnel by using microtunnelling boring machine (MTBM). The analyses were done in a few separate cases by using 2D-Finite Element modeling. The models were differentiated according to three tunnel shapes which are circular, horseshoe and square. Each tunnel had been analyzed according to the effect of the pipe roof tunnel to depth (0.0d, 0.5d, 1.0d and 2.0d) and spacing between twin tunnels (0.0d, 0.5d, 1.0d and 2.0d). The last part of the analyses is the verification study on a pipe roof tunnel project at Padang Rengas, Perak. A simple ground profile of the tunnel project had been created by using the information gathered from the bore log of the in-situ. Based on the analyses, the results had shown that the settlement has been reduced up to 90% with the installation of pipe roof system. As the tunnel depth increase, the magnitude of settlement above the tunnel has reduced up to 60%. Meanwhile, for the twin tunnels, the magnitude of settlement has increased up to 70% at the second tunnel due to the excavation of the first tunnel that cause disturbance to the soil strength. The magnitude of settlement of a twin tunnels also reduced from up to 58% when the spacing between the tunnels increase.
Effect of pipe roof support on the ground settlement induced by shallow tunnel excavation_Mohd Fandey Abdul Latif_A9_2016_MYMY