Analysis And Control Technology Of Different Settlement Of Bridge Transition Section In Widening Highway Road

The reconstruction and expansion of highways in my country is still in the development stage,and there is insufficient research on the characteristics and control technology of vertical and horizontal differential settlements and the control technology of bridge abutment structure stability for the upgrading of low-grade highways to the widening of the transition section of highway bridges.Therefore,this article relies on the lotus plant high-speed reconstruction and expansion project,using a combination of on-site monitoring and numerical simulation to widen the roadbed and bridge transition section of the low-to-high highway subgrade vertical and horizontal differential settlement characteristics,abutment structure stress displacement characteristics and differences The settlement control technology was studied.The main research conclusions are as follows:(1)A survey and summary of the low-to-high road project,and the use of old roads should consider the low design standards,insufficient compaction,and high roadbed humidity.On-site monitoring of the settlement of the widened side foundation was carried out,and the settlement law of the foundation settlement from the new road slope to the joint was increased first and then decreased,and the settlement increased overall with the increase of the distance from the monitoring section to the back of the platform.(2)From the field geotechnical test of fully weathered granite,the curves of the mechanical parameters of subgrade fillings in various layers of the roadbed with the moisture content were obtained.Geostudio was used to establish a humidity field calculation model to obtain the moisture curve of the roadbed with time.Zones 93,94,and 96 reached equilibrium moisture contents of 21.3%,20.5%,and 12.8%on the 7th,12th,and 13a,respectively,combined with geotechnical test results.The long-term changes of the mechanical parameters of the soil in each layer of the subgrade were obtained.The changes in the humidity of the subgrade greatly reduced the soil parameters in the areas 93 and 94.(3)ABAQUS was used to establish the widening model of the road and bridge transition section,and the vertical and horizontal differential settlement of the transition section and the force displacement of the abutment were obtained.The post-construction settlement of the cross-section pavement is 3.0cm at the new shoulder,and the differential settlement is 2.3cm;The differential settlement in the longitudinal section is concentrated within 15m from the back of the platform.The differential settlement after work is 3.0cm.The 2a platform is staggered by 2.9cm.The platform is offset to.the front of the platform.The horizontal displacement of the platform on the new road side is uniformly distributed in the horizontal direction.The road side gradually decreases from the junction to the old shoulder.(4)Analysis of vertical and horizontal differential settlement control technologies such as foundation replacement,old road replacement,geotechnical materials,lightweight backfill,bridge head slab,etc.,and the control effect of each technology is obtained.The foundation replacement and light backfilling significantly reduce the differential settlement,and the slab can effectively avoid the wrong platform;the widening side and the single side replacement EPS light soil are more reasonable than the old roadside synchronous replacement,and the single side replacement can be reduced The lateral displacement of the small abutment is 41%,and the vertical stress is significantly reduced within 15m behind the abutment and 54.6%at 5.5m.