6 DIFFERENT TYPES OF WEATHERING OF ROCK MASS

weathering of rock mass

WEATHERING OF ROCK MASS ‘Weathering is the process of alteration and breakdown of rock and soil materials at and near the Earth’s surface by chemical decomposition and physical disintegration’ (Geological Society Engineering Group Working Party Report, 1995). Of particular note in this definition is that weathering is described as a process. It is not a … Read more

HOW TO DESCRIBE ROCK MASS CHARACTERISTICS ON SITE?

Fig-1- Illustration of 13 parameters used for describing rock mass characteristics

DESCRIPTION OF ROCK MASS CHARACTERISTICS Standardized geologic mapping and logging procedures should be used for describing rock mass characteristics. The types of information collected will depend on site access, extent of rock outcrops, and the criticality of the proposed structure to be constructed on or in the rock mass. A method proposed by the International … Read more

HOW TO CALCULATE CORE RECOVERY AND RQD OF ROCK?

Illustration on Core Recovery and RQD calculation

Core Recovery and RQD (Rock Quality Designation) The easiest way to characterize the amount of material recovered during rock coring is to calculate “core recovery” as the amount (i.e. length) of recovered material divided by the total length of the core run (presented as a percentage). Rock Quality Designation (RQD) is a modified core recovery … Read more

SAFE BEARING CAPACITY VALUES OF DIFFERENT SOILS & ROCKS

on site identification & classification of soil

Values of Safe Bearing Capacity The safe bearing capacity of soil should be determined on the basis of soil test data or by performing some field test such as Standard penetration test or Plate load test etc. However, in the absence of soil test data, the values of safe bearing capacity (S.B.C) as given in … Read more

HOW TO ESTIMATE STRENGTH AND MODULUS OF ROCK FROM SPT VALUES?

Igneous rocks

Strength and Modulus of Weathered Rock from SPT Values In the weathered rock it is difficult to drive the split sampler to the full specified depth as in soil. Hence we may estimate the strength and elastic modulus values of weathered rock by driving the spt apparatus for a fixed number of blows and find … Read more

12 BASIC QUALITY REQUIREMENTS OF GOOD BUILDING STONES

Stone masonry

No single stone can satisfy all the below mentioned quality requirements. For example, strength and durability requirement contradicts ease of dressing requirement. Hence it is necessary that site engineer looks into the properties required for the intended work and selects the stone accordingly. Requirements of Good Building Stones The following are the quality requirements of … Read more

WHAT ARE THE ENGINEERING AND PHYSICAL PROPERTIES OF STONES?

Engineering and physical properties of stones

Engineering & Physical Properties of Stones The following are the engineering and physical properties of the stones that should be looked into before selecting them for engineering works: 1. Structure The structure of the stone may be stratified (layered) or unstratified. Structured stones should be easily dressed and suitable for super structure. Unstratified stones are … Read more

HOW TO CLASSIFY ROCKS? (ENGINEERING CLASSIFICATION OF INTACT ROCK)

Engineering classification of rock

This method of rock classification was introduced by Deer & Miller in the year 1996. Two parameters are considered while classifying rocks on this method, which are Uniaxial compressive strength Modulus of elasticity Step by Step Method to Classify Rock Based on Engineering Parameters) This method of rock classification consists of 3 steps, as given … Read more

HOW TO CLASSIFY ROCKS BASED ON DEGREE OF WEATHERING?

Classification Based on Degree of Weathering of Rock Mass Rocks can be classified on the basis of its degree of wreathing. These type of rock classification gives the engineer qualitative idea of rock mass. This type of classification is generally done on site and only by a through visual inspection rocks can be classified. While … Read more