Aplikasi standard proctor pada roller compacted concrete (RCC) dengan bahan additive viscocrete-10

SIMANJUNTAK, Marihot, Dr. Ir. Iman Satyarno, M.E

2008 | Tesis | S2 Magister Sistem dan Teknik Transportasi

Penggunaan perkerasan Roller Compacted Concrete (RCC) atau Beton Padat Giling (BPG) di Indonesia masih jarang dijumpai tapi sudah mulai diminati, misalnya pada jalan tol, Aircraf parking, Aprons, Industrial facilities, terminal, persimpangan, dan lain-lain. Kondisi perkerasan jalan aspal (perkerasan lentur) di Indonesia dihadapkan pada permasalahan beban kendaraan yang sulit dikendalikan dan iklim tropis, curah hujan relatif tinggi yang sangat mempengaruhi kinerja perkerasan jalan sehingga menyebabkan kerusakan sebelum waktunya (aspal terkelupas, jalan bergelombang dan berlobang). Penelitian benda uji RCC ini menggunakan bahan lokal sebagai bahan susun RCC yaitu agregat kasar dengan ukuran maksimum 20 mm dari Clereng, agregat halus dari Merapi, Semen tipe I dari Gresik, FAS 0,4, Slump nol ditambah viscocrete-10=0,75% berat semen. Benda uji RCC dipadatkan dengan aplikasi standard proctor, mould Ø 15,24 cm, tinggi 11,65 cm dengan variasi jumlah tumbukan 3x28, 3x42, dan 3x56 pukulan. Pengujian dilakukan terhadap kuat tekan dan kuat tarik belah silinder yaitu 27 benda uji kuat tekan dan 27 benda uji kuat tarik belah pada umur 1, 7, dan 28 hari. Hasil penelitian menunjukkan bahwa pengaruh variasi jumlah tumbukan sangat menentukan dalam peningkatan berat beton dan tingkat kepadatan beton RCC, jika dibandingkan dengan kepadatan teoritis maksimum, derajat kepadatan 91,55% tertinggi pada 56 tumbukan umur 1 hari. Kepadatan hasil gyratory compactor 100 putaran, lebih tinggi 12,06% dari standard proctor, kuat tarik belah dan kuat tekan lebih tinggi 47,68%&48,24%. Pengaruh standard proctor terhadap peningkatan kuat tekan, signifikan pada tumbukan antara 3x28 dan 3x56 tertinggi pada umur 7 hari dengan perbandingan (1:1,408). Terhadap peningkatan kuat tarik belah tertinggi pada umur 7 hari (1 : 1,421 ). Kuat tarik belah (fct) benda uji (RCC) pada umur 28 hari tertinggi 13% dari kuat tekan (fc’), pada 56 tumbukan setelah dikonversi menjadi flexural strength (fcf) lebih tinggi dari yang disyaratkan untuk perancangan perkerasan RCC atau BPG yaitu 4,165 MPa > 3,3 MPa. Kuat tekan rata-rata benda uji (fc’) tertinggi pada 56 tumbukan, umur 28 hari 25,57 MPa memenuhi kuat tekan beton kelas III dengan mutu > K 225 ( 25,57 MPa > 18,675 Mpa), sehingga disain dan aplikasi standard proctor ini dapat diterapkan pada RCC di lapangan namun alat pemadat yang mendekati kondisi lapangan adalah giratory compactor. Penggunaan viscocrete-10 (0,75% berat semen) masih kurang efektif dalam mengurangi jumlah semen pada proporsi 256 kg/m3.

Roller Compacted Concrete (RCC) Pavement or Beton Padat Giling (BPG) is seldom used in Indonesia but it has been started to apply, for example at turnpike, aircraft parking, aprons, industrial facilities, terminal, junction, and others. The condition of asphalt concrete pavement (flexible pavement) in Indonesia has caused problems related with vehicles carriage which difficult to be controlled, tropical climate and high rainfall has influenced the road, i.e. pavement damages earlier than it supposed to (asphalt scrape, rough and crack road). This research applies local material as the component of RCC, i.e. coarse aggregates with maximum size of 20 mm taken from Clereng, fine aggregates taken from Merapi, Semen type I taken from Gresik, with water cements ratio of 0.4, zero Slump, additive viscocrete-10=0.75% of cements weight. The specimen RCC is compacted by standard proctor application for compact concrete, mould Ø 15.24 cm, height 11.65 cm with various number of hammerings 3x28, 3x42, and 3x56 blows. Assaying is done to compressive strength and tensile splits strength platen, i.e. 27 compressive strength specimens and 27 tensile strength specimens splits at the age of 1, 7, and 28 days. The result of the research indicates that influence various hammering amounts is significant in the improvement of concrete weight and level of density of concrete RCC if it is compared to theoretical maximum density, the highest degree of density is 91.55% and it’s reached at 56 hammerings at age 1 day. Density result of gyratory compactor 100 gyrations, 12.06% higher from standard proctor, splitting tensile strength is 47.68% higher from standard proctor and compressive strength is 48.24% higher than standard proctor. Towards the improvement of compressive strength, standard proctor is significant at the hammering between 3x28 and 3x56 and it is highest at the age of 7 day with comparison (1:1.408). Towards the improvement of splitting tensile strength, standard proctor is highest at the age of 7 day (1 : 1.421). Splitting Tensile strength (fct) specimen (RCC) at the age of highest 28 days of 13% from compressive strength (fc'), by 56 hammerings after converted into flexural strength (fcf) higher from required for scheme of concreting RCC, i.e. 4.165 MPa > 3.3 MPa. The average of specimen compressive strength (fc') is highest by 56 hammerings, life 28 days 25.57 MPa, fulfilling class concrete compressive strength III with grade > K 225 ( 25.57 MPA > 18.675 Mpa), so that the design and the application of this standard proctor are applicable at RCC in field, however ramming closing condition of field is giratory compactor. The use of viscocrete-10 (0.75% cements weight) is still less effectively in decreasing the number of cements at proportion of 256 kg/m3.

Kata Kunci : Standard proctor,RCC,Viscocrete,10,FAS dan kadar semen rendah,Kuat tekan dan kuat tarik belah,Standard Proctor, RCC, Viscocrete-10, WCR and low cements grade, Compressive and splitting tensile strength