Kegiatan manusia secara langsung atau tidak langsung maupun akibat proses alam menyebabkan kualitas udara turun sampai ke tingkat tertentu sehingga menyebabkan lingkungan menjadi kurang atau tidak dapat berfungsi lagi sesuai peruntukannya. Semakin meningkatnya pertumbuhan suatu kota beriringan dengan meningkatnya kegiatan manusia dan bertambahnya jumlah kendaraan di perkotaan  maka mengakibatkan komposisi udara ambien mengalami perubahan kualitas. Terjadinya penurunan kualitas udara diakibatkan kendaraan bermotor di jalan yang padat. Akibat penurunan kualitas tersebut dapat mengganggu dan membahayakan lingkungan sekitar terutama manusia, hewan serta tumbuhan. Penelitian ini dilakukan di tiga lokasi di Kota Medan dengan tingkat kepadatan lalu lintas yang cukup tinggi, yaitu Jalan Gatot Subroto, Jalan Gagak Hitam, Jalan Sisingamangaraja. Dari hasil analisis menggunakan Statistical Package for the Social Sciences (SPSS) diketahui bahwa volume lalu lintas berpengaruh signifikan terhadap kualitas udara ambien. Umumnya pengaruh tersebut didominasi oleh angkutan barang sedangkan angkutan penumpang hanya memberikan pengaruh yang kecil, namun pengaruh tersebut dapat bertambah besar apabila volume lalu lintas padat di suatu jalan. Untuk besaran pengaruh kinerja lalu lintas terhadap kualitas udara ambien sebesar 28,07% dan sisanya di pengaruhi faktor lain. Hasil tersebut cukup besar untuk satu parameter pencemar udara di perkotaan.

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Various research and experiments in the field of concrete is done as an effort to improve the quality of concrete, materials technology and implementation techniques obtained from the results of research and experiment, it is intended to answer the higher demands on the use of concrete and overcome the constraints that often occur in the implementation of the concrete work in the site. The purpose of this research was to compare the value of compressive strength of normal concrete with compressive strength of concrete using SikaFume and clamshell. The compositions of the SikaFume mixture used in this research were 5% and 8% and for the shellfish used were also 5% and 8% of the weight of cement for all variations. The test specimens used were cylindrical, the planned concrete quality was 45 MPa tested at 21 days and 28 days with prior curing before testing. This research tested concrete with cylindrical test object for compression test of 30 specimens and consisted of 2 variations and each variation of 5 samples. From this research, it was found that the highest concrete compressive strength was found in the 8% SikaFume addition concrete mix and 8% shellfish at 28 days old that is 45.62 MPa when compared with the normal concrete.

Trains are means of transportation that are used by people to avoid traffic congestion. However, train stations are also most frequently exposed to noise. This is due to the sound intensity of the operational activities in the location. Passengers and station officers are environmental components exposed to noise. In this study, the value of sound intensity level at the railway station of Medan city is measured using Sound Level Meter. This measurement was carried out for six days. The highest sound intensity level for the train departures is 96,67 dB and for the train arrival is 96,66 dB. Meanwhile, the lowest sound intensity level of train departures is 81,41 dB and the arrival of trains is 83,75 dB. It was found that the high level of sound intensity is sourced from the friction of the wheels with the rail surface, notification speakers and train horns. The results of this study can be used to find the most appropriate solution to reduce the noise level in the railway station area.

Asphalt/bitumen is a brownies black material, is viscous so it will soften and melt when it gets enough heating. In general, asphalt is obtained from petroleum refining. Pavement construction in Indonesia, both road rehabilitation project, maintenance and construction of roads, generally. Pertamina 60/70 asphalt is used as a binder for the asphalt mixture. Apart from pertamina asphalt, there are several types of asphalt that ore often used in projects in Indonesia, one of which is esso 60/70 asphalt.Esso asphalt is a type of asphalt produced from foreign companies outside of Indonesia, so it is necessary to do a comparative research test on the Marshall Properties and the stiffness modulus of asphalt. The research was conducted to analyze the stress-strain relationship which show the stiffness and strength of the asphalt material by experimenting with several test objects using the Marshall tool. If the value of the stiffness modulus decreases, asphalt aging will occur which causes the pavement to crack easily when receiving heavy loads. The stiffness modulus analysis of the asphalt mixture is an analytic procedure for planning and evaluating the performance of asphalt mixture. Asphalt mixture is a material that is not perfectly elastic, so the use of the term modulus of elasticity (E) is not suitable, instead the term mixed stiffness modulus is used. The data needed is the value of the stiffness of the asphalt content mixture which was tested by the laboratory to obtain the stiffness modulus and asphalt content characteristic.