Electronic Theses and Dissertation

Penelitian ini bertujuan untuk mengembangkan makromodel alternatif berbasis equivalent strut bagi portal beton bertulang dengan dinding pengisi bata yang diperkuat ferrocement. Pendekatan penelitian dibagi menjadi empat tahap: (1) pemilihan teknik perkuatan paling optimal untuk wilayah rawan gempa (Aceh), (2) optimasi konfigurasi material perkuatan (ferrocement), (3) kalibrasi persamaan kontribusi geser murni ferrocement, dan (4) validasi makromodel alternatif melalui pengujian siklik portal skala penuh.
Pada Tahap I, pemilihan teknik perkuatan dilakukan dengan mengintegrasikan Analytical Hierarchy Process (AHP) dan Multi-Criteria Decision Analysis (MCDA). Sepuluh pakar menilai enam teknik perkuatan berdasarkan lima kriteria: kinerja, ekonomi, durabilitas, kemudahan penerapan, dan ketersediaan model analitis. Hasil AHP menghasilkan bobot prioritas: Kinerja (25,51%), Ekonomi (24,81%), Ketahanan (19,19%), Model Analitis (17,60%), dan Kemudahan Penggunaan (12,89%) dengan rasio konsistensi CR = 0,0246. Analisis sensitivitas pada lima pembobotan mengonfirmasi ferrocement sebagai teknik terbaik (skor 0,77), mengungguli FRP (0,63), Steel Strip (0,57), post-Tensioning (0,51), Shotcrete (0,49), dan TRM (0,37).
Pada Tahap II, konfigurasi optimal ferrocement ditentukan melalui uji push-off pada specimen Z dengan ketebalan 4 cm dan variasi lapisan wiremesh 0–5 lapis (rasio tulangan 0%–0,39%). Hasil menunjukkan bahwa konfigurasi tiga lapis (ρ=0,24%) merupakan syarat minimum agar wiremesh berkontribusi positif namun tetap efesien, dengan peningkatan kapasitas geser 22,1% dan koefisien variasi terkecil (5,25%). Sebaliknya, satu lapis (0,08%) menurunkan kapasitas 11,9%, dan dua lapis (0,16%) hanya memberikan peningkatan 3,7% yang tidak signifikan, sementara empat lapis dan lima lapisan wiremesh, dengan mutu mortar yang lebih tinggi yaitu sebesar menghasilkan kapasitas geser 82,0% dan 105,8%.
Pada Tahap III, kalibrasi persamaan kontribusi geser murni ferrocement dilakukan dengan regresi linear. Kontribusi mortar diformulasikan sebagai V_{cpredcl\ }, sedangkan kontribusi wiremesh diformulasikan sebagai V_{spredcl}. Persamaan gabungan dinotasikan sebagai V_{npredcl} memiliki koefisien determinasi R² = 0,9882, menandakan akurasi prediksi yang sangat tinggi.
Pada tahap akhir, makromodel alternatif divalidasi melalui uji siklik displacement control (FEMA 461). Kapasitas frame terkoreksi diintegrasikan dengan kapasitas dinding termodifikasi (power law untuk efek skala) dan kontribusi ferrocement yang diperoleh dari kalibrasi push-off. Dari integrasi ini, dirumuskan dua alternatif makromodel untuk lebar strut komposit, yaitu pendekatan langsung: W_{smf}\ (l) dan pendekatan empiris sederhana: W_{smf}(e). Kedua model mampu mereproduksi kapasitas geser komposit dengan akurasi mendekati 100% pada spesimen uji.
Kesimpulannya, makromodel alternatif yang dihasilkan praktis karena hanya memerlukan parameter geometri dan material dasar yang mudah diperoleh di lapangan, sehingga direkomendasikan sebagai alat estimasi kapasitas geser portal beton bertulang dengan dinding bata diperkuat ferrocement dalam evaluasi bangunan eksisting.

This research aims to develop an alternative macromodel based on the equivalent strut concept for reinforced concrete frames with brick infill walls strengthened by ferrocement. The study comprises four stages: (1) selection of the optimal strengthening technique for earthquake-prone regions (Aceh), (2) optimization of reinforcement material configuration (ferrocement), (3) calibration of the pure shear contribution equation of ferrocement, and (4) validation of the alternative macromodel through full-scale portal cyclic testing. In Stage I, the strengthening technique selection was performed by integrating the Analytical Hierarchy Process (AHP) and Multi-Criteria Decision Analysis (MCDA). Ten local experts evaluated six strengthening techniques based on five criteria: performance, economic aspect, durability, ease application of use, and availability of analytical models. The AHP results yielded priority weights: Performance (25.51%), Economic Aspect (24.81%), Durability (19.19%), Analytical Model Availability (17.60%), and Ease of Application (12.89%), with a consistency ratio CR = 0.0246. Sensitivity analysis across five weighting scenarios confirmed ferrocement as the best technique (score 0.77), outperforming FRP (0.63), Steel Strip (0.57), post-Tensioning (0.51), Shotcrete (0.49), and TRM (0.37). In Stage II, the optimal ferrocement configuration was determined through push-off tests on Z-specimens with a thickness of 4 cm and wiremesh layer variations of 0–3 layers (reinforcement ratios 0%–0.24%). The results showed that the three-layer configuration (ρ=0.24%) is the minimum requirement for the wiremesh to contribute positively, achieving a shear capacity increase of 22.1% and the lowest coefficient of variation (5.25%). Conversely, the single-layer (0.08%) decreased capacity by 11.9%, and the two-layer (0.16%) provided only an insignificant increase of 3.7%. In Stage III, the pure shear contribution equation of ferrocement was calibrated using linear regression. The mortar contribution was formulated as V_{cpredcl\ }, while the wiremesh contribution was formulated as V_{spredcl}. The combined equation (V_{npredcl}) achieved a coefficient of determination R² = 0.9882, indicating excellent predictive accuracy. In the final stage, the alternative macromodel was validated through displacement-controlled cyclic testing (FEMA 461). The corrected frame capacity was integrated with the modified masonry wall capacity (using a power law to account for size effects) and the actual ferrocement contribution derived from the push-off calibration. From this integration, two alternative macromodels for the equivalent composite strut width were formulated, namely the direct approach: W_{smf}\ (l), and the empirical approach: W_{smf}(e).Both models successfully reproduced the composite shear capacity with deviations approaching 100% on the test specimens. Since they require only basic geometric parameters and material properties, these macromodels are recommended as practical tools for the seismic evaluation of existing buildings.” In conclusion, the resulting alternative macromodel is practical as it only requires basic geometric parameters and material properties that are easily obtainable in the field. Therefore, it is recommended as a reliable estimation tool for the shear capacity of reinforced concrete frames with ferrocement-strengthened brick infill walls in seismic evaluation of existing buildings.