DAFTAR ISI Abstrak ...................................................................................... i Kata Pengantar ......................................................................... v Daftar Isi ................................................................................. vii Daftar Tabel............................................................................ xii Daftar Gambar ....................................................................... xiv BAB I PENDAHULUAN ........................................................ 1 1.1 Latar Belakang.......................................................... 1 1.2 Perumusan Masalah .................................................. 4 1.3 Maksud dan Tujuan .................................................. 5 1.4 Batasan Masalah ....................................................... 5 1.5 Lokasi Perencanaan .................................................. 6 1.6 Sistematika laporan................................................... 7 BAB II TINJAUAN PUSTAKA .............................................. 9 2.1 Beton Pratekan.......................................................... 9 2.1.1 Konsep Dasar Beton Pratekan ......................... 9 2.1.2 Keuntungan Beton Pratekan.......................... 10 2.1.3 Kehilangan Gaya Pratekan ............................ 11 2.2 Balok Menerus........................................................ 19 2.2.1 Keuntungan balok menerus ........................... 19 2.2.2 Koordinat c.g.s .............................................. 20 2.2.3 Profil kabel konkordon.................................. 21 2.2.4 Daerah limit kabel ......................................... 22 2.3 Momen Batas .......................................................... 22 2.4 Momen Retak ......................................................... 24 2.5 Gaya Membelah ...................................................... 25 2.6 Gaya Geser ............................................................. 26 2.7 Geser Horisontal ..................................................... 27 2.8 Profil I ..................................................................... 28 2.9 Pembebanan Kereta Api di Indonesia..................... 30 2.9.1 Jaringan jalan rel di Indonesia....................... 30 2.9.2 Peraturan pembebanan .................................. 30 2.9.3 Perbandingan beberapa jenis pembebanan kereta api di berbagai negara ............................................ 33 BAB III KRITERIA DESAIN ............................................... 35
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3.1 Data Perencanaan ................................................... 35 3.1.1 Data-data teknis............................................. 35 3.1.2 Data-data bahan............................................. 35 3.1.3 Tegangan ijin bahan ...................................... 36 3.1.4 Peraturan dan literatur yang digunakan......... 37 3.2 Persyaratan Desain ................................................. 38 3.2.1 Pembebanan pada struktur utama jembatan .. 38 3.2.2 Aksi dan beban tetap ..................................... 38 3.2.3 Beban lalu lintas kereta api ........................... 39 3.3 Konsep Desain (Design Statement) ........................ 40 3.4 Sistematika Metodologi....................................... 42 BAB IV PERENCANAAN STRUKTUR SEKUNDER ....... 49 4.1 Perhitungan Pelat Lantai Kendaraan (bak Ballast) . 49 4.1.1 Pembebanan bak ballast................................ 50 4.1.2 Perhitungan momen ...................................... 54 4.1.3 Penulangan pelat lantai bak ballast ............... 58 4.1.3.1 Perhitungan penulangan arah bentang memanjang Lx ................................................. 58 4.1.3.2 Perhitungan penulangan arah bentang memanjang Ly ................................................. 60 4.1.3.3 Kontrol dinding penahan tepi bak ballast ......................................................................... 61 4.1.4 Kontrol lendutan, lebar retak plat dan geser ponds ............................................................... 61 4.2 Perhitungan Diafragma ........................................... 63 4.2.1 Pembebanan .................................................. 64 4.2.2 Penulangan geser........................................... 64 4.2.3 Penulangan tarik di tengah bentang .............. 66 4.3 Perhitungan Shear Connector ................................. 67 4.3.1 Perhitungan lebar efektif beton penampang komposit ................................................................. 67 4.3.2 Gaya geser ..................................................... 67 4.3.3 Perhitungan shear connector ......................... 67 4.3.4 Kekuatan shear connector ............................. 68 4.3.5 Jumlah stud yang dipakai .............................. 68
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BAB V PERENCANAAN STRUKTUR UTAMA ............... 69 5.1 Pre-Elemenary Desain ............................................ 69 5.1.1 Uraian Kondisi Setempat .............................. 69 5.1.2 Alternatif Desain ........................................... 69 5.2 Perencanaan Gelagar Utama ................................... 70 5.2.1 Karakteristik gelagar utama .......................... 70 5.2.2 Perhitungan penampang komposit ................ 73 5.3 Perhitungan Pembebanan ....................................... 76 5.3.1 Beban gravitasi............................................... 76 5.3.2 Beban longitudinal ......................................... 78 5.3.3 Beban lateral .................................................. 79 5.4 Kombinasi Pembebanan Perencanaan Balok.......... 80 5.5 Perhitungan Momen dan Gaya dalam Balok .......... 83 5.5.1 Perhitungan gaya prategang ........................... 84 5.5.2 Material beton prategang ............................... 85 BAB VI ANALISA BALOK MENERUS I ........................... 87 6.1 Analisa Prategang ................................................... 87 6.1.1 Perencanaan gaya prategang awal (Fo) ......... 87 6.1.2 Perhitungan daerah limit kabel cgs ............... 88 6.1.3 Perencanaan lintasan kabel ........................... 91 6.1.4 Perhitungan momen sekunder dan garis C .... 95 6.2 Perencanaan Letak Koordinat Kabel ...................... 98 6.3 Perhitungan Kehilangan Gaya Pratekan ............... 100 6.3.1 Kehilangan pratekan akibat perpendekan elastisitas (elastomic shortening) .......................... 100 6.3.2 Kehilangan pratekan akibat gesekan kabel (friction and wobble effect) ................................................. 102 6.3.3 Kehilangan pratekan akibat slip angker (slip anchorage) ............................................................ 105 6.3.4 Kehilangan pratekan akibat rangkak beton (creep) 6.3.5 Kehilangan pratekan akibat susut beton (shrinkage) ............................................................ 107 6.3.6 Kehilangan pratekan akibat relaksasi (relaxation) 6.4 Kontrol Tegangan ................................................. 111 6.4.1 Kontrol tegangan.......................................... 112
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6.4.2 Kontrol momen batas dan momen retak ...... 118 6.4.3 Kontrol tegangan pada balok angker ........... 121 6.4.4 Perhitungan lendutan ................................... 123 6.5 Perhitungan Gaya Membelah ............................... 126 6.5.1 Penulangan Geser......................................... 128 BAB VII ANALISA BALOK MENERUS II ...................... 135 7.1 Analisa Prategang Struktur Balok Menerus II ...... 135 7.1.1 Perhitungan daerah limit kabel cgs ............. 136 7.1.2 Perencanaan lintasan kabel ......................... 139 7.1.3 Perhitungan momen sekunder dan garis C .. 143 7.2 Perencanaan Letak Koordinat Kabel .................... 146 7.3 Perhitungan Kehilangan Gaya Pratekan ............... 148 7.3.1 Kehilangan pratekan akibat perpendekan elastisitas (elastomic shortening) .......................... 148 7.3.2 Kehilangan pratekan akibat gesekan kabel (friction and wobble effect) ................................................. 151 7.3.3 Kehilangan pratekan akibat slip angker (slip anchorage) ............................................................ 153 7.3.4 Kehilangan pratekan akibat rangkak beton (creep) 7.3.5 Kehilangan pratekan akibat susut beton (shrinkage) ............................................................ 156 7.3.6 Kehilangan pratekan akibat relaksasi (relaxation) 7.4 Kontrol Tegangan ................................................. 159 7.4.1 Kontrol tegangan.......................................... 160 7.4.2 Kontrol momen batas dan momen retak ...... 170 7.4.3 Kontrol tegangan pada balok angker ........... 173 7.4.4 Perhitungan lendutan ................................... 174 7.5 Perhitungan Gaya Membelah ............................... 177 7.6 Perencanaan perletakan ........................................ 179 BAB VIII METODE PELAKSANAAN .............................. 185 8.1 Prinsip Tahap Konstruksi ..................................... 185 8.2 Metode Produksi Girder ....................................... 185 8.2.1 Tahapan Produksi......................................... 185 8.2.2 Tahapan Persiapan ....................................... 186 8.3 Transportasi ke Tempat Konstruksi ...................... 192
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8.4 Tahap Pelaksanaan Post Tensioning Girder ......... 193 8.4.1 Tahap Persiapan.................................... 193 8.4.2 Tahap Pelaksanaan ............................... 194 8.4.3 Tahap Akhir .......................................... 195 BAB XI KESIMPULAN DAN SARAN.............................. 199 DAFTAR PUSTAKA LAMPIRAN GAMBAR
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