Research and Application of Key Technologies for the Construction of Cemented Material Dam with Soft Rock

Abstract

In order to safely and efficiently use soft rock aggregate cemented dams in red bed regions and promote the development of widely sourced cemented sand and gravel dam materials, the Jinjigou project in China applied soft rock for the first time in the construction of cemented material dams. This article further explores the concept of cemented material dams from conducting on-site direct shear tests and research on soft rock material ratios and explores and invents a new structure and construction method by combining soft rock cemented sand and gravel with cemented rockfill. This article also proposes a digital mixing and intelligent dynamic control method for cemented material dams with soft rock. The research results show that soft rock aggregate content not exceeding 60% can produce soft rock cemented gravel with a compressive strength of no less than 6 MPa. The stress on the dam body is small and does not produce tensile stress. The dam body with added soft rock has certain shear-bearing capacity, with a shear friction coefficient of 0.99~1.10 MPa, cohesion of 0.26~0.53 MPa, and high residual strength, accounting for 60~80% of the peak strength. At the same time, the problems of large fluctuations in moisture content and the uneven grading of the soft rock and riverbed gravel mix during the mixing and production process, and the significant influence on safety caused by the large strength dispersion of the cemented sand and gravel, are resolved, ensuring the quality of soft rock cemented sand and gravel preparation. The successful application of soft rock cemented material dams in Jinjigou has achieved a breakthrough in key technologies for soft rock cemented dam construction in red bed regions, proving the feasibility of soft rock cemented material dam construction and having broad prospects for application and promotion.

Research on Settlement and Section Optimization of Cemented Sand and Gravel (CSG) Dam Based on BP Neural Network

“…(3) The material of the overburden matches the Mohr Coulomb constitutive model. (4) The material of the dam body matches the Duncan Zhang constitutive model modified by rigid spring method. (5) The contact surface between the dam body and the covering layer is in complete contact.…”

“…In recent years, CSG dams have received increasing attention, and many scholars have begun to study their material properties and structural characteristics. Jia [4] explored and invented a new structure and construction method by combining soft rock CSG material with cemented rockfill, and implemented an intelligent dynamic control technology that can achieve noncontact rapid detection and rapid feedback regarding aggregate gradation water content and clay content. Yang [5] conducted an antisliding stability analysis of a CSG dam, calculated the surface and internal antisliding stability between the dam layers, and reasonably determined the parameters for antisliding stability analysis between the dam layers.…”