Housing or residential buildings constitute a primary necessity for all human beings. Beyond merely providing a place for rest, housing also serves as protection against environmental elements such as rain, sunlight, and other external threats.

Therefore, in building construction, it is essential to carefully consider not only aesthetic aspects but also the long-term durability of the structure.

As one of the most commonly used composite materials in construction projects, concrete offers relatively high compressive strength and durability. This is achieved because concrete fundamentally consists of a mixture of cement, water, and natural aggregates such as sand and gravel. This composition provides strong bonding properties, enabling concrete, in theory, to withstand and evenly distribute structural loads.

Nevertheless, concrete is not without its limitations. Several critical issues must be considered in concrete-based construction, including deterioration or compromised structural integrity caused by poor casting practices. Such deficiencies can ultimately reduce the quality of existing concrete structures.

In response to these concerns, students from the Civil Engineering Program at Universitas Dian Nusantara (UNDIRA) adopted a Non-Destructive Testing (NDT) approach to evaluate existing concrete using the Ultrasonic Pulse Velocity (UPV) technique. The study was conducted on a reinforced concrete residential project located on Jl. Martimbang, South Jakarta.

Unlike destructive methods such as the splitting tensile test, the UPV technique is considered both effective and efficient, as it allows for evaluation without damaging the existing structure. Consequently, it not only saves time but also eliminates material waste and additional post-testing costs.

The UPV method operates based on the propagation of ultrasonic waves through concrete or other materials using a PUNDIT (Portable Unit Non-Destructive Indicator Tester) device. Initially, a transducer emits ultrasonic waves with frequencies ranging from 24 to 150 kHz, assisted by a coupling gel. A receiver then records the travel time of the transmitted waves. Through this process, students are able to assess the homogeneity, density, and internal structural integrity of concrete without dismantling the structure.

According to ASTM C597-16 and IS 13311 standards for material quality assessment, higher recorded wave velocities indicate better quality and greater density of the existing concrete.

The field study was conducted at 35 column points in the building’s basement, covering a land area of 2,800 m². Data collection was based on pulse velocity classifications, where values greater than 4500 m/s are categorized as excellent, 3500–4500 m/s as good, 3000–3500 m/s as average, and less than 3000 m/s as doubtful, indicating potential structural deficiencies.

Based on UPV test results from the 35 basement columns, the average velocity was recorded at 3387.56 m/s, with the highest value reaching approximately 3350 m/s, and a relatively insignificant standard deviation. These findings indicate that the residential project on Jl. Martimbang demonstrates fairly good concrete quality with a satisfactory level of homogeneity. However, the evaluation also revealed a small number of samples with values ranging from 3296 to 3310 m/s, suggesting the presence of defects, potentially due to casting errors or internal voids.

The application of Non-Destructive Testing using the Ultrasonic Pulse Velocity (UPV) technique has proven to be an effective approach for evaluating concrete quality. This study confirms that UPV can provide a comprehensive understanding of the internal condition of concrete without compromising structural integrity, making it a reliable method. Accordingly, UPV results significantly support accurate technical decision-making in the field.

The involvement of Civil Engineering students from UNDIRA in this research reflects the active role of academic communities in addressing real-world challenges in the construction industry. Moving forward, the students propose further research development using the Rebound Hammer instrument, enabling additional analysis of concrete deformation levels to complement the existing evaluation of concrete density.