Research On Comprehensive Utilization Of Acetylene Sludge In Highway Engineering

In recent years,with the continuous advancement of China's sustainable development strategy,new requirements have been put forward for road engineering construction to achieve green and environmentally friendly goals.At the same time,a series of eco-environmental problems caused by solid wastes such as acetylene sludge?AS?,coal gangue,construction waste,etc.generated in the process of industrialization and urbanization are currently hot issues that need to be resolved urgently.Therefore,it is of great significance to find new methods to recycle industrial wastes such as AS,coal gangue,construction waste,etc.,and to solve the problems of shortage of raw materials faced by the road engineering.This study intends to use AS/fly ash?FA?as a kind of binder in road base/subbase materials,relevant experimental studies have been carried out on comprehensive stabilization of solid wastes such as coal gangue and construction waste,in order to look forward to applying these industrial wastes to road engineering.The main work is as follows:?1?In order to study the effect of AS on the environment,a series of experiments were conducted on the physical and chemical properties of AS,including X-ray fluorescence analysis?XRF?,power X-ray diffraction analysis?XRD?,thermogravimetric analysis?TG?,corrosion analysis,etc.The test results show that the original shape of the AS is off-white,the water content is generally above 30%,and part of it is agglomerated,but easy to break up.The main mineral component in AS is Ca?OH?₂,and the effective calcium and magnesium content is as high as 72.5%.No radioactive and heavy metal elements were detected in the AS.The p H value of AS is generally below 12.5,which does not belong to the category of hazardous solid waste in national standards.?2?For roadbeds in road engineering,some experiments were conducted on the stability of soils with different properties by AS or AS/FA,including heavy compaction test,unconfined compressive strength test,indirect tensile strength test,compressive resilient modulus test and resistant to water damage test.The results showed that AS can significantly improve the mechanical properties of soil with higher plasticity index.For soil with lower plasticity index,AS/FA can be used to improve its mechanical properties.The water stability coefficient of the soil modified by AS or AS/FAis mostly between 0.6?0.8,showed that water has a certain inhibitory improvement effect of AS modified soil.?3?The experimental research on AS/FA-stabilized coal gangue was carried out for the base/subbase of pavement in road engineering,including heavy compaction test,unconfined compressive strength test,indirect tensile strength,and compressive resilient modulus test.The results showed that using the voids volumetric ratio of coal gangue as the control index and using the volumetric ratio to determine the mixing ratio of the mixture can met the requirements of the road bases at all levels for the lime and FA stabilized materials.The particle distribution of coal gangue has an important effect on the development of the strength of AS/FA-stabilized coal gangue.The greater the content of fine aggregate in gangue,the more beneficial it is to the development of the strength of the AS/FA-stabilized coal gangue.?4?The experimental research on AS/FA-stabilized recycled brick and concrete debris was carried out for the base/subbase of pavement in road engineering,including heavy compaction test,unconfined compressive strength test,indirect tensile strength,and compressive resilient modulus test.The results showed that although the engineering properties of recycled brick and concrete debris is poor,they were stabilized by low amounts of AS and FA,and the 7th-day unconfined compressive strength were high,which fully met the road bases at all levels requirements for lime and fly ash stabilized materials.However,in view of the poor engineering properties of recycled brick and concrete debris,it is recommended to be used as the subbase material and not recommended for bases in actual engineering.