---
title: "Meaning of grade 43 cement"
subject: "Civil Engineering Materials"
chapter: 5
key: "semester_3/civil_engineering_materials:grade-43-cement"
source: https://www.bctengineer.com/q/semester_3/civil_engineering_materials/grade-43-cement
site: BCT Engineering
---

# Meaning of grade 43 cement

Civil Engineering Materials · Chapter 5: Cement

- Asked in: 2068 Baisakh, 1 marks
- Video: [33 Grade vs 43 Grade vs 53 Grade of Cement](https://www.youtube.com/watch?v=xqb5x4gqTBA) — Engineering Motive
- Answer checked by Claude Opus 5.5 (high effort) on 2026-10-14
- Page: https://www.bctengineer.com/q/semester_3/civil_engineering_materials/grade-43-cement
- Whole chapter: https://www.bctengineer.com/md/semester_3/civil_engineering_materials/chapter-5

## Question

What is meant by grade C-43 cement?

## Short answer

Grade 43 cement is ordinary Portland cement with a minimum 28-day compressive strength of 43 MPa on standard 70.6 mm mortar cubes. Its 3-day and 7-day strengths are at least 23 MPa and 33 MPa respectively.

## Answer

Grade 43 cement (IS 8112) is ordinary Portland cement whose 28-day compressive strength, tested on standard 70.6 mm mortar cubes (1:3 cement-sand), is **not less than 43 MPa (N/mm²)**. Its 3-day and 7-day strengths are at least 23 MPa and 33 MPa.

## Check yourself

The answer's key points as multiple-choice questions, with the correct option and why.

1. Grade 43 cement means:
   A. 7-day strength 43 MPa
   B. Initial setting 43 min
   C. 28-day strength not less than 43 MPa
   D. 43% lime
   Answer: C. Tested on 70.6 mm mortar cubes. (Key point: Meaning)

2. Mortar for the test is:
   A. 1:1
   B. 1:6
   C. 1:2:4
   D. 1:3 cement:sand
   Answer: D. Standard sand cubes. (Key point: Cube test)

3. 3-day and 7-day strengths of grade 43 are at least:
   A. 23 and 33 MPa
   B. 27 and 37 MPa
   C. 43 and 53 MPa
   D. 13 and 23 MPa
   Answer: A. 27 and 37 are for 53 grade. (Key point: 3 and 7 day)

## Related in Civil Engineering Materials

- [7 and 28 day strength of 53 grade OPC](https://www.bctengineer.com/question.md?key=semester_3%2Fcivil_engineering_materials%3Aopc-53-grade-strength) — Civil Engineering Materials, chapter 5
- [Cement manufacture with flow diagram](https://www.bctengineer.com/question.md?key=semester_3%2Fcivil_engineering_materials%3Acement-manufacture-flow-diagram) — Civil Engineering Materials, chapter 5, asked 5×

## Related in other subjects

- [Grade of cement; Bogue's compounds](https://www.bctengineer.com/question.md?key=semester_5%2Fconcrete_technology_and_masonry_structure%3Agrade-of-cement-bogue) — Concrete Technology and Masonry Structure, chapter 1