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Bridge design in Indonesia adhere to the regulations outlined in SNI 1725:2016, the Bridge Loading Standard. Under this standard, vehicle loads are currently represented as idealized forms of the actual loads they impose. Recent technological advancements have enabled the real-time measurement of vehicle loads as they traverse bridges, providing a more accurate representation of the actual loads experienced. Weigh-In Motion (WIM) technology, consisting of sensors installed on bridge elements, captures the responses of these elements to traffic loads. The primary objective of this research is to assess the characteristics of actual traffic loads, generate traffic load simulations using WIM data, and conduct a comparative analysis between the actual traffic loads derived from WIM data and the planned traffic loads specified by SNI 1725:2016. This study utilized WIM data collected from the Kaligawe Bridge in Semarang and simulated its application on a 60 m span simple steel frame bridge using the Monte Carlo method. The comparative analysis of the internal force values derived from WIM data against those planned according to SNI 1725:2016 revealed that the internal force ratios ranged from 86% to 97%. These findings indicate that the actual traffic loads measured through WIM technology on the Kaligawe Bridge result in lower internal forces compared to the standard loads specified in SNI 1725:2016. [ABSTRACT FROM AUTHOR]

An investigation has been made to perceive the correlation of normal concrete compressive strength between the destructive and non-destructive test method. The non-destructive method used Ultrasonic Pulse Velocity Test. Meanwhile, destructive method used a concrete compressive test. Testing the compressive strength of concrete using cylinder concrete samples. The cylinder concrete samples used in this study had a concrete mix design of 25 MPa and 30 MPa. Each sample was tested destructive and non-destructive to get the compressive strength value relationship. Based on the result, the regression model proposed to estimate the compressive strength of concrete is the first regression model which is f'ce=0,0037v1+12,346. The results are validated using column structure located in K2F Room on BINUS Syahdan campus. The validation result shows the estimated compressive strength from the linear regression model is higher than the projected compressive strength of the concrete column. [ABSTRACT FROM AUTHOR]

Noise is the main issue that commonly occurs in taking and processing the signal. The noise may interfere with the first vibration mode frequency based on the results of Fast Fourier Transform. Previous study carried out using signals with sinusoidal functions has been able to minimize the noise in a signal. However, there is limited information about the time or location the frequency value of a signal takes place. For this reason, wavelet transforms are reapplied in reconstructing signals to provide information on the frequency and time. In this study, signal data with sinusoidal functions is used with a specified frequency of 0.25 Hz. The signal data is subjected to noise with a range of standard deviation 0.1 - 1.0. Wavelet analysis used is Haar wavelet, while the signal filtering process used high-pass and low-pass filter. The filtering lengths used are 8 (23) and 32 (25), so it will produce 8*8 and 32*32 Haar wavelet analysis matrics. The results show that the specified frequency value can be determined using signal analysis with Haar wavelet analysis and signal reconstruction. The higher the scale paramater value (j) is used in signal analysis and filtering, the higher range of noise values can be reduced. The results also indicated that the signal frequency can be obtained when there is a similar pattern between the reconstruction and original signal. [ABSTRACT FROM AUTHOR]

In expressing sinusoidal waves mathematically with the addition of the amplitude parameters, the equation becomes x(n) = SAn sin 2pfnt. Signals in the form of sinusoidal waves can experience interference when getting frequency readings. This interference is caused by the presence of noise in the sinusoidal wave signal. In this study, the amplitude of sinusoidal signal and noise will be compared to determine how much noise affects frequency readings. The method adopted to transform discrete data x(n) into frequency is the Discrete Fourier Transform. Based on the results obtained, when the amplitude value in discrete data is greater than the noise value, frequency readings are defined and clear. Noise value double the value of the amplitude value can still yield frequency readings from a structure; however, results are barely comprehensible. [ABSTRACT FROM AUTHOR]

Analog signals are generally expressed by sinusoidal waves, where sinusoidal waves are the basis for all forms of analog signals. The important parameters of the sinusoidal signal equation are frequency (fn) and sample rate (fs) which are formulated with the equation x(t) = sin 2pfnt. The time parameter in the t variable in the sinusoidal equation is the duration of data collection for the sinusoidal signal. Frequency data in this study uses two models, namely the first model with a frequency value of f1 = 0.25Hz, f2 = 1.5Hz, f3 = 3Hz and the second model with a frequency value of f1 = 0.25Hz, f2 = 2Hz, f3 = 4.25Hz. The sample rate (fs) used for both models is 8 Hz with a total time duration of 32 seconds. The method used in transforming the time domain of a sinusoidal signal into a frequency domain is using the Discrete Fourier Transform. The results obtained for the first model, namely the reading of the frequency value of f1 = 0.25Hz, f2 = 1.5Hz, f3 = 3Hz can still be read clearly. As for the second model, the frequency value of f1 = 0.25Hz, f2 = 2Hz, f3 = 4.25Hz can still be read. However, a new frequency appears between the frequency readings of f2 = 2Hz and f3 = 4.25 Hz, with a frequency value of f = 3.75Hz. This is because the use of the sample rate (fs = 8 Hz) is smaller than 2 times the signal frequency (2 fn). Therefore, the Nyquist theory in the case study of the second model does not meet the equation fs > 2 fn. [ABSTRACT FROM AUTHOR]