|Table of Contents|

Analysis on reasonable anchor length of tensile anchor(PDF)

长安大学学报（自然科学版）[ISSN:1006-6977/CN:61-1281/TN]

Issue:
2022年5期
Page:
43-51
Research Field:
道路工程
Publishing date:

Info

Title:
Analysis on reasonable anchor length of tensile anchor
Author(s):
MA Tian-zhong1; 2; 3;  AN Zi-shen1; 2; 3;  ZHOU Yong1;  WANG Zheng-zhen1; 2; 3;  SU Tian-tao1; 2; 3;  GAO Hong1; 2; 3
(1. School of Civil Engineering, Lanzhou University of Technology, Lanzhou 730050, Gansu, China; 2. Key Laboratory of Disaster Mitigation in Civil Engineering of Gansu Province, Lanzhou University of Technology, Lanzhou 730050, Gansu, China; 3. Western Center of Disaster Mitigation in Civil Engineering, Ministry of Education, Lanzhou University of Technology, Lanzhou 730050, Gansu, China)
Keywords:
road engineering;  slope engineering;  anchoring system;  anchoring length;  anchor rod inclination;  rod diameter
PACS:
U417.116
DOI:
10.19721/j.cnki.1671-8879.2022.05.005
Abstract:
Aiming at the main structure of the anchoring system was often embedded in the rock mass, and the existing calculation formula for the length of the anchoring section is too complicated, and the geotechnical engineering practitioners mostly use the empirical method for design and construction. The method of combining theoretical derivation and practical engineering was adopted and started with the force analysis of the anchor rod micro-element. The force balance equation of the micro-element of the anchoring section was given and the formula of the ultimate pull-out bearing capacity of the anchor was obtained. Based on this, the improved formula for calculating the reasonable anchorage length of the bolt was derived. Combined with the current specification, the effective variation range of the reasonable anchoring length of the tension anchor was given. By changing the size of the incident angle of the bolt, the geometric relationship distribution diagram of the internal force of the bolt was combined. After deducing the change of the inclination angle of the anchor rod, the correction method of the length calculation of the anchoring section was obtained. After exploring the variation law of the diameter of the bolt body, the reasonable variation range was given. And based on an actual slope project in Lanzhou City, the rationality of the reasonable anchorage length range of the anchorage section calculated by this formula was verified. The results show that in the same supporting structure, the anchoring length of the anchor rod with a large incident angle is usually increased, which verifies the rationality of the proposed anchoring length correction method after the anchor rod inclination angle changes. It is concluded that the main factors affecting the pullout resistance of the bolt are the interface shear strength parameters, the length of the anchoring section, the diameter of the borehole, etc., but the values must be increased within a certain range to effectively improve the supporting capacity of the supporting system.3 tabs, 8 figs, 21 refs.

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Last Update: 2022-09-30