在柔软的土壤上建造堤防:对轻质材料和深度替代技术的比较研究
Fathi M Abdrabbo1, Khaled E Gaaver1, Amr Z Elwakil1
1Structural Engineering Department, Faculty of Engineering, Alexandria University, Alexandria, Egypt.
Scientific reports
|November 28, 2024
概括
轻质材料和深层替换技术显著减少堤防沉积和对弱土壤的压力. 与混凝土堆相比,深度混合柱在土壤再利用方面特别有效.
科学领域:
- 地质技术工程 地质技术工程
- 土木工程 土木工程是指土木工程.
- 土壤力学 土壤力学
背景情况:
- 在薄弱土壤上的堤防施工需要仔细的材料选择和稳定性增强.
- 遵守建筑规范和可持续性标准对于现代基础设施项目至关重要.
研究的目的:
- 评估轻量填充材料和弱土壤堤防的深层替换技术的有效性.
- 用数值分析比较各种土壤改善方法的性能.
主要方法:
- 使用2D有限元软件 (Plaxis 8) 进行数值建模.
- 将轻质材料 (木,地质泡) 与使用深层替换技术 (混凝土堆,深层混合柱,石柱,沙堆) 改进的传统填充物进行比较.
- 分析了应力分布,孔隙水压和沉积.
主要成果:
- 轻质材料减少了11-98%的沉积量和5-89%的应力.
- 深度替代技术减少了8.5-75%的结算和44-88%的压力.
- 与混凝土堆相比,深度混合柱在促进土壤再利用方面表现优越.
结论:
- 轻质材料和深层替代技术都为在弱土壤上建造堤提供了可行的解决方案.
- 技术的选择影响了沉积,压力减轻和土壤再利用潜力.
- 由于其在土壤再利用中的有效性,建议使用深度混合柱.
相关概念视频
01:19Design Example: Maintaining Level of an Embankment
52
Constructing a roadway embankment over uneven terrain requires precise leveling to ensure stability and proper drainage. Surveyors use a leveling instrument and staff to calculate ground elevations and determine the required fill material at each point along the embankment alignment.The process begins by positioning a leveling instrument near a benchmark with a known elevation. A backsight reading establishes the instrument height, which serves as a reference for subsequent measurements. A...
52
01:17Placing Concrete
80
The concrete is placed as close as possible to its final position to avoid segregation. The placed concrete is then fully compacted to expel the entrapped air, and the next layer of concrete is laid while the underlying layer is still in the plastic state. The rate at which concrete is placed and compacted is kept equal.
While placing concrete, care is taken to ensure that the concrete is laid in uniform layers, and hand shoveling and moving concrete using poker vibrators is avoided. Also,...
While placing concrete, care is taken to ensure that the concrete is laid in uniform layers, and hand shoveling and moving concrete using poker vibrators is avoided. Also,...
80
01:14Design Example: Managing Concrete Workability
74
This example deals with managing the workability of concrete for a raft foundation project under hot weather conditions. Workability is crucial for ensuring the concrete is easy to place, compact, and finish. In this scenario, a slump test — a common method to measure the workability of fresh concrete — initially indicated low workability. This was attributed to the rapid water loss from the concrete mix, exacerbated by the high temperatures causing the course aggregates to heat up.
74
01:29Preplaced Aggregate Concrete
92
Preplaced aggregate concrete is ideal for construction environments that are not easily accessible. The process begins by properly wetting the gap-graded coarse aggregates to remove the dirt, then placing it in the form and compacting it. Voids are filled with a mortar mix pumped under pressure through slotted pipes. This mortar typically consists of Portland cement, pozzolan, fine aggregates, water, and a fluidizing aid. The pozzolan helps reduce bleeding and segregation while improving the...
92
01:20Slump Test
157
The slump test is a widely used method to measure the workability of concrete. It employs a 12-inch high truncated cone mold that tapers from eight inches at the base to four inches at the top. Before testing, the mold is securely attached to a flat base and dampened.
Concrete is poured into the mold in three layers to conduct the test. Each layer is compacted 25 times with a steel tamping rod, which has a five-eighths-inch diameter and a rounded end, to ensure even distribution and eliminate...
Concrete is poured into the mold in three layers to conduct the test. Each layer is compacted 25 times with a steel tamping rod, which has a five-eighths-inch diameter and a rounded end, to ensure even distribution and eliminate...
157
01:12Non-destructive Tests for Concrete Strength
110
The rebound hammer test, also known as the Schmidt hammer test, is a non-destructive technique for evaluating the hardness of concrete and, indirectly, the strength of concrete. It operates on the principle that the rebound of a spring-driven mass from a concrete surface correlates to the surface's hardness. The device comprises a mass within a tubular housing, a spring mechanism, and a plunger that strikes the concrete. Upon release, the energy imparted to the mass by the spring causes it...
110