Analyse Structural Damage And Research On Remedial Measures Of The Crushed Stone Cement Base During Construction

As the base’s curing period is over, traffic transportation vehicles work repeatedly for a long time on the base’s surface in the construction. It can lead to the pavement structural strength being lost in various degree because of the bearing system of pavement structure has not been completed. The structural damage during construction could be act as cracks in base, pot holes and scaling on the surface. If it wasn’t been controled, the structural strength would be lost more and lost entirely at last as the pavement’s structure being destroyed at that time. Presently, research for stabilized macadam-cement base is focused on the materials’ parameter-design, design of mixture ratio, anti-crack technology, etc., but the research for structural damage during construction is less and not comprehensive enough. Therefore, the research and analysis of this dissertation is focused on the structural damage’s investigation during the construction, analysis of cause, preventive measures, remedial measures and other aspects.Through the investigation of structural damage based on the project, the survey show that subbase’s structural damage is most severe, lower base is second, upper base is on the minimum level. The drill core sampling and deflection tests show that: when the damage during the construction period appears, the uniformity of the thickness of pavement structure would be seriously affected and the ability of bearing structure would be decreased. In order to analyze the structural layer’s stress when the structural parameters change, Bisar3.0 software has been selected to do the calculational work. The results show that whether the subbase thickness decreases, modulus increases or lower base thickness and modulus decrease are lead to the subbase maximum stress with varying degrees increasing, and will reduce the fatigue life of subbase. The main reason of structural damage during the construction period are the procedure of construction’s unreasonable arrangements and the severely overloaded transport vehicles’ working on the base’s surface for a long time.The research show that using the single shot shaping technique can effectively present structural damage during construction. The semi-rigid base with layered construction molding technology can also prevent damage of structure during construction by restricting the axle load of the construction vehicle. The strength of pavement structure which damaged during the construction period could use the remedial measures to restore the strength to the original design of pavement, such as increasing the thickness and strength of paving layer. So it can reduce the loss which from the crushed stone cement base’s structural damage during construction.From this research, the preventive and remedial measures for the structural damage during construction could be used as a reference for similar projects.