*Article* **Laboratory Methods for Assessing the Influence of Improper Asphalt Mix Compaction on Its Performance**

### **Michał Wróbel, Agnieszka Woszuk and Wojciech Franus \***

Department of Geotechnical Engineering, Faculty of Civil Engineering and Architecture, Lublin University of Technology, Nadbystrzycka 40, 20-618 Lublin, Poland; m.wrobel@pollub.pl (M.W.); a.woszuk@pollub.pl (A.W.)

**\*** Correspondence: w.franus@pollub.pl; Tel.: +48-815-384-416

Received: 6 May 2020; Accepted: 26 May 2020; Published: 29 May 2020

**Abstract:** Compaction index is one of the most important technological parameters during asphalt pavement construction which may be negatively a ffected by wrong asphalt paving machine set, weather conditions, or the mix temperature. Presented laboratory study analyzes the asphalt mix properties in case of inappropriate compaction. The reference mix was designed for AC 11 S wearing layer (asphalt concrete for wearing layer with maximum grading of 11 mm). Asphalt mix samples used in the tests were prepared using Marshall device with the compaction energy of 2 × 20, 2 × 35, 2 × 50, and 2 × 75 blows as well as in a roller compactor where the slabs were compacted to various heights: 69.3 mm (+10% of nominal height), 66.2 mm (+5%), 63 mm (nominal), and 59.9 mm (−5%) which resulted in di fferent compaction indexes. Afterwards the samples were cored from the slabs. Both Marshall samples and cores were tested for air void content, sti ffness modulus in three temperatures, indirect tensile strength, and resistance to water and frost indicated by ITSR value. It was found that either insu fficient or excessive level of compaction can cause negative e ffect on the road surface performance.

**Keywords:** asphalt mix; compaction index; volumetric parameters; sti ffness modulus; moisture resistance
