Analysis on structural disease characteristics and laws of lining in long-serving pipeline tunnel
In order to clarify the ontology structural health status of oil and gas pipeline tunnels under long-term service,47 mountain tunnels of oil and gas pipelines that had been in service from 2007 to 2024 and never been repaired and reinforced were taken as the engineering basis.Based on the field investigation and historical detection results of tunnel lining diseases,the statistics on the original accumulation situation of ontology structural diseases of pipeline tunnels was conducted in detail.The indexes of structural technical status,maintenance attention and disease density were introduced,and the diseases were quantitatively analyzed.Finally,the overall service status of the tunnel and the development characteristics and laws of six types of diseases were determined.The results show that most of the oil and gas pipeline tunnels are in normal service with in-juries.The frequency of lining cracking is the highest and far greater than other diseases.The floor cracking and uplift,lining deterioration,secondary under-thickness and lining defects often occur,and the probability of section intrusion limit is low.The vertical wall lining type makes the lining cracks dominated by longitudinal crack evenly distributed in all parts of tunnel,with short and narrow characteristics.With the increase of crack width or length,the proportion of cracks decreases.The strength of lining concrete in nearly half of the tunnels has deteriorated below the design strength,and the deterioration degree of low-grade concrete is much higher than that of high-grade concrete.The probability of occurrence at the arch waist of sec-ondary lining under-thickness vault is the highest,and the defect length at the vault is much larger than those of other parts.The lining disease density of grade V surrounding rock section is the smallest,and the advance support and radial system bolt effectively reduce the probability of disease occurrence.The increase of longitudinal slope does not lead to the increase of tun-nel disease density,and there is no obvious correlation between tunnel disease and longitudinal slope of tunnel.The research results can provide reference for the reuse of old oil and gas pipeline tunnels.
oil and gas pipelinemountain tunnelontology structurestatistical analysisstructural disease
NETL
NSTL
万方数据
