Ask Question, Ask an Expert


Ask Civil Engineering Expert

problem 1: When a confined explosive charge is detonated in a blasthole, four events occur very rapidly but sequentially. Describe each of the four events briefly.

problem 2: An open pit blast consists of 120 vertical blastholes. Bench height is 10m and 1m of subdrilling is undertaken. The holes have 2.5m of stemming. Blasthole diameter is 200 mm, the burden is 6 m and spacing is 7 m. An emulsion explosive of specific gravity 1.1 is used. What is the powder factor? (Note consider the emulsion only, ie. do not consider primers)

problem 3: What is the importance of stemming in relation to blasting?

problem 4: Find the voltage required to detonate 40 electric detonators connected in series joined to 250m of firing cable with 50m of connecting wire. Resistances are as follows: average 2.2 ohms per detonator, 0.11 ohm per m of connecting wire and 0.04 ohms per m there and back for the twin core firing cable. Assume a DC supply is available.

problem 5: Determine the voltage and power input for a parallel firing circuit consisting of 25 detonators of resistance 1.6 ohms. The circuit is connected to 350m of firing cable of resistance 0.001 ohms.

problem 6: A new coal mining operation is to be worked employing surface mining using blasting to clear an overburden of Shale using 120mm holes and 13m benches. Dry rock conditions are anticipated and the decision is to use bulk ANFO with emulsion cartridges as a primer. A staggered drilling pattern with S = 1.15B is to be employed. If density of compacted ANFO = 0.85 g/cm3 and PF = 0.6 kg/m3, find out the burden and spacing.

problem 7: Describe the methods available for secondary blasting.

problem 8: For a schist orebody determine a ring drilling pattern assuming pneumatically loaded ANFO is used of density 0.9, in 56mm diameter blastholes of average length 11m. Detail any assumptions you make.

problem 9: Flyrock, airblast and ground vibrations are common problems in blasting, what methods can be used to minimise their impact both within the mine and to the population living in the area around a mine?

problem 10: Describe the construction of a typical electric detonator. Electric initiation of charges can be problematic in certain ore body types, why is this? What other methods of initiation of explosive initiation are available.

Civil Engineering, Engineering

  • Category:- Civil Engineering
  • Reference No.:- M98023

Have any Question? 

Related Questions in Civil Engineering

Te force system consists of the force p - 300i 200j

The force system consists of the force P = - 300i + 200j + 150k lb and the couple C. Determine the magnitude of C if the moment of this force system about the axis DE is 800 lb · ft.

Taking the role of a sustainability consultant you are

Taking the role of a Sustainability Consultant you are asked to prepare a report offering guidance to your client (Oman Eco-towns) as they seek to establish a future development strategy for establishing an Eco-town near ...

In this problem you will design a digital stopwatch with

In this problem you will design a digital stopwatch with the following characteristics: Its display will consist of two two-digit decimal numbers representing minutes and seconds. The smallest display will be OO:OO, the ...

1 regarding the overturning of a shearwall describe the

1. Regarding the overturning of a shearwall, describe the possible vertical soil bearing pressure diagrams. Give the formulas that are used to obtain the maximum soil pressure for the two distributions. 2. Refer to Fig. ...

An n-bit updown counter is a sequential circuit with a

An N-bit up/down counter is a sequential circuit with a clock input and an up/down control input. Wen control is 1, the circuit counts up, modulo 2N, on each rising edge of the clock. In other words, the present-state ou ...

A common approach to the addition of nbit binary numbers

A common approach to the addition of n,bit binary numbers uses n cascaded combinational modules, each a l-bit adder (conventionally called a full adder). Full-adder modules can be combined as follows to implement a circu ...

In this classic problem you are to design a single

In this classic problem, you are to design a single finite-state machine S that will be connected in an arbitrarily long one-dimensional string as follows: Each FSM in the string is connected by k wires to its left and r ...

The airflow system in prob 760 is measured with a venturi

The airflow system in Prob. 7.60 is measured with a venturi having like dimensions as the orifice, i.e., the same pipe diameter and throat diameter. Calculate the flow rate in kg/s for the same pressure and temperature m ...

1 devise a scheme for representing rational numbers as

1. Devise a scheme for representing rational numbers as binary strings. Briefly describe algorithms for performing addition and comparison using your scheme. 2. Devise a scheme for representing rational numbers and ratio ...

1 is it possible for a one-input one-output combinational

1. Is it possible for a one-input, one-output combinational circuit built entirely of two-input NAND gates to contain a hazard? Either draw such a circuit or explain why one cannot be built. 2. Is it possible for a Combi ...

  • 4,153,160 Questions Asked
  • 13,132 Experts
  • 2,558,936 Questions Answered

Ask Experts for help!!

Looking for Assignment Help?

Start excelling in your Courses, Get help with Assignment

Write us your full requirement for evaluation and you will receive response within 20 minutes turnaround time.

Ask Now Help with Problems, Get a Best Answer

WalMart Identification of theory and critical discussion

Drawing on the prescribed text and/or relevant academic literature, produce a paper which discusses the nature of group

Section onea in an atwood machine suppose two objects of

SECTION ONE (a) In an Atwood Machine, suppose two objects of unequal mass are hung vertically over a frictionless

Part 1you work in hr for a company that operates a factory

Part 1: You work in HR for a company that operates a factory manufacturing fiberglass. There are several hundred empl

Details on advanced accounting paperthis paper is intended

DETAILS ON ADVANCED ACCOUNTING PAPER This paper is intended for students to apply the theoretical knowledge around ac

Create a provider database and related reports and queries

Create a provider database and related reports and queries to capture contact information for potential PC component pro