The practice of subcontracting selection emphasizes two important goals: the company's strategic goal to maximize profits by partnering with subcontractors and the project's operational goal for obtaining qualified subcontractors. Both goals are achieved by formulating the best multi-criteria weights. This is not easy to implement due to differences in subjectivity, viewpoint, and other consideration of assessors, but prioritizing the criterion weights can reduce these differences. This study presents an ANN (Artificial Neural Network) with the ability to generalize data. The purpose of the study is to develop an ANN model for subcontracting selection and to identify significant criteria related to the company's strategic goal. The initial training of the proposed ANN model utilized 40 subcontractor selection datasets containing data in the form of a subcontractor selection scheme consisting of 20 criteria and 5 major groups. Training of ANN model was successful with MSE learning at 1.37269e -7 , MSE validation at 0.07985, and epoch 600 to 800. The quotation price is the significant criterion of the selection, and it has a great outcome for the contractor strategic goal. The interaction between the subcontractor selection practice and the ANN model shows that the ANN has an important role in the subcontractor selection practice.

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Clay soil behavior often becomes problematic with building construction, it is about the shrink-swell behavior in clay when influenced by water content. Coconut husk fiber (coir fiber), in general, is an industrial waste which is still infrequent to be re-used. This study aims are to determine the effect of coir fiber addition for mechanical stabilization of clay soil in terms of CBR (California Bearing Ratio) value. Soil samples used for laboratory tests were collected from Ulee Glee area of Pidie Jaya Regency. According to AASHTO classification, the soil category is A-7-5 (25) while for USCS classification, the soil is OH (Organic High). The percentage of added coir fiber was 0%, 0.2%, 0.4% and 0.6% of the dry weight of the soil with a coir fiber length of 2 and 3 cm. Two treatments of clay-coir fiber mixing method were applied namely direct mixing and mixing by layers. The results of natural soil compaction test obtained that OMC (Optimum Moisture Content) value and dry soil weight (γdmax) was 26.8% and 1.34 gr/cm3 respectively. The highest CBR results were obtained for clay soil with 0.4% coir fiber 3 cm (direct mix) with CBR value = 17.7%. Furthermore, the lowest CBR value is 10% for percentage of 0.2% with coir fiber length 2 cm (by layer). In general, high organic clay soil with coir fiber mixture addition is able to increase the CBR values if compared to CBR of natural soil which is 8.15%. Thus, the use of coir fiber in this study is able to improve soil bearing capacity which is useful for construction material in the site.

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Due to repeated loads, the pavement structures will experience repeated stresses and strains resulting in permanent deformation even though the working loads are still smaller than the design load. The permanent deformation will lead to cracking and fatigue failure with the life of the pavement. This phenomenon can be reduced by increasing the stiffness, flexibility, durability, stability and water absorption of the pavement. Material modification including the utilization of waste tire rubber (WTR) and natural zeolite is one of the efforts to increase those parameters in semi flexible pavement (SFP). The aim of this study therefore, to assess the deformation and fatigue failure of SFP incorporating WTR and natural zeolite under cyclic loading. The WTR was used as an additive at the level of 3% of asphalt content while natural zeolite was used as cement replacement at the 0, 5, 15 and 25% replacement levels. Permanent deformation tests were conducted by applying wheel tracking loads with the pressure of 6.4 ± 0.15 kg/cm2 on the surface of the specimens with 1260 cycles per hour while fatigue tests were conducted on the simple supported beams with the span length of 30 cm by applying forth point loading at the frequency of 10 Hz. The test results showed that the best performance in sustaining cyclic loading was achieved at the zeolite content of 5%.

Industrial solid wastes have become a difficult problem in some developing countries, especially in Indonesia. The environmentally friendly issue regarding how to decrease industrial wastes by reuse or recycling process has become famous in recent years. Coffee husk ashes in this research were attained from burned waste coffee husk which can be considered as solid waste material from the coffee processing industry. In this study, clay soil obtained from Cot Bagie Village, Blang Bintang, Aceh was mixed with coffee husk ashes. Several soil physical properties test was conducted such as specific gravity, Atterberg limit, and grain size distribution by following ASTM standard. The physical parameter of soil was evaluated with the addition of 3%, 6%, 9%, and 12% coffee husk ashes by soil dry weight. The result shows that the physical properties of soil were improved if compared to untreated soil. A further mechanical laboratory test in soil mechanics was suggested for more advanced analysis of effect in soil-coffee husk ashes mixing.

The objective of this research is to study the compressive strength of semi-flexible pavement by using waste tire rubber and natural zeolite as asphalt and cement replacements. The mix design of porous asphalt is started with a determination of optimum asphalt proportion with open-graded aggregate as specified in Australian Asphalt Pavement Association (AAPA) 2004. The asphalt was then replaced by 3 %, 4 % and 5 % of waste tire rubber and the Marshall test were conducted. The cement mortar with 0 %, 5 %, 10 %, 15 % and 20 % natural zeolite was injected to porous asphalt specimens. The compressive strength test was conducted based on ASTM C670-91a at the age of the specimens of 14 days. The test results showed that the higher compressive strength is reached at the 15 % natural zeolite and 5 % waste tire rubber, which is 15,43 MPa.

Earthquake catastrophe in Pidie Jaya has caused damages to the city of Meureudu, Aceh-Sumatra Indonesia. Based on preliminary study for buildings and infrastructures, the geotechnical engineering aspects damages-related are presented. Seismic motion effect damage of earthquakes such as liquefaction of soil, lateral spreads, and ground failure were the majority effect for infrastructures and buildings. Moreover, failures of almost of multi-storey buildings and mosques along the national road lines are because the effect of peak surface accelerations and earthquake wave propagation forces which are very close with epicenter coordinates 5.308°N / 96.269°E in 4km radius. Seismic back investigates of the Aceh's fault seismic source as well as initial probabilistic seismic hazard analysis post-Pidie Jaya earthquake for city of Mereudu is offered. Liquefaction potential analysis from the estimation of peak ground acceleration was conducted. Geotechnical aspect and substructure failure characteristics to infrastructure and housing damages due earthquake are also reported. The earthquake has caused 104 people deaths, 2.474 unit houses in total need to be rehabilitated and rebuilt, almost 10 km of roads and 50 bridges need to be reconstructed. Some descriptive countermeasures for reconstructions of geotechnical engineering aspects and mitigation are also provided.