Praktikum Perkerasan Jalan Raya - Modul 7 Pemeriksaan Indeks Kepipihan dan Kelonjongan Agregat

Summary

This video provides a detailed explanation of a laboratory procedure for testing the flatness and elongation indices of coarse aggregates used in road construction. Following the SNI Part 137 standard from 1996, the test involves sieving the aggregates, performing elongation and flatness tests, and weighing the aggregates to determine the percentage of each shape. The results help assess the suitability of aggregates for use in asphalt mixtures. The video also emphasizes the importance of accurate measurement and calculation in ensuring the quality of construction materials.

Takeaways

• 😀 The video explains the practical process of testing road pavement materials, specifically focusing on the SNI 137 standard from 1996.
• 😀 The purpose of the experiment is to test the flatness and elongation index of coarse aggregates used in asphalt mixtures.
• 😀 Key equipment for the experiment includes sieves, a set of elongation and flatness tools, a 30 kg weighing scale, and containers.
• 😀 The aggregate material used in the experiment is coarse aggregate that is retained in sieves with a 1/2 inch and 3/8 inch mesh size.
• 😀 The procedure begins by preparing the necessary materials and equipment, then setting up sieves in the correct order.
• 😀 After setting the sieves, the coarse aggregate is placed into them until it reaches a weight of 2.5 kg.
• 😀 Once the 2.5 kg threshold is reached, the aggregate that remains on the sieve is collected for further testing.
• 😀 The elongation test involves positioning the aggregate lengthwise and crosswise to measure the elongation index.
• 😀 After performing the elongation test, the weight of the aggregate retained in the elongation tool is measured.
• 😀 The flatness test is similar, where the aggregate is positioned lengthwise to determine the flatness index, and the weight is measured again.
• 😀 After both tests, the results are recorded, calculations for flatness and elongation are made, and the tools are cleaned and returned after the experiment.

Q & A

What is the main objective of this practical experiment?

The main objective is to test the flatness and elongation indices of coarse aggregates, ensuring their suitability for use in asphalt mixtures for road construction.

Which standards are referenced in the experiment for testing aggregates?

The experiment follows the SNI standard, specifically SNI Part 137 from the year 1996, for testing the flatness and elongation indices of coarse aggregates.

What materials are used in this practical experiment?

The materials used include coarse aggregates that pass through 1/2-inch and 3/8-inch sieves, with a total sample weight of 2.5 kg for testing.

What equipment is required for the experiment?

The required equipment includes sieves (1/2-inch and 3/8-inch sizes), elongation and flatness index tools, a balance with a 30 kg capacity, and containers for weighing and holding aggregates.

What is the procedure for conducting the elongation test?

For the elongation test, the aggregates are placed in the elongation tool, then measured by passing them through the appropriate sieve, and the weight of the aggregates that pass through each sieve is recorded.

How is the flatness test performed in this experiment?

The flatness test is done by placing the aggregates into the flatness index tool. The aggregates are measured based on their shape, and the weight of aggregates passing through the sieves is recorded.

How much aggregate is needed for the experiment?

A total of 2.5 kg of coarse aggregates is needed for the experiment, with the sample divided across the two sieves (1/2-inch and 3/8-inch).

What do the flatness and elongation indices indicate?

The flatness and elongation indices indicate the shape characteristics of the coarse aggregates. High elongation and flatness values suggest aggregates may not perform well in asphalt mixtures, affecting road durability.

What should be done after completing the experiment?

After the experiment, the measurements are recorded, calculations are performed for the flatness and elongation indices, and the equipment should be cleaned and returned.

Why is it important to measure the flatness and elongation of aggregates?

Measuring the flatness and elongation of aggregates is crucial because these characteristics affect the performance and stability of the asphalt mix. Aggregates with excessive flatness or elongation may result in weaker or less durable roads.