CN1858019A

CN1858019A - Self compacting high strength mortar

Info

Publication number: CN1858019A
Application number: CN 200610027202
Authority: CN
Inventors: 钟世云; 吴冲
Original assignee: Tongji University
Current assignee: Tongji University
Priority date: 2006-06-01
Filing date: 2006-06-01
Publication date: 2006-11-08
Anticipated expiration: 2026-06-01
Also published as: CN100336767C

Abstract

The present invention belongs to the field of building material technology, and is especially one kind of self compacting high strength mortar. The self compacting high strength mortar consists of portland cement, stone powder, silica fume, expansion agent and water reducing agent of polycarboxylate in certain weight proportion. The self compacting high strength mortar with new type of water reducing agent has very low flowability loss, 28 day compressive strength as high as 70-90 MPa and construction convenience and low cost.

Description

A kind of self compacting high strength mortar

Technical field

The invention belongs to building material technical field, be specifically related to a kind of self compacting high strength mortar, can be as the grouting material.

Background technology

In recent years, the application of the skeleton construction of close muscle configuration is more and more, because bar spacing is very little, building such concrete structure is not easy to vibrate, need to use the concrete that the self-compacting function is arranged, therefore, the application of whole world self-compacting concrete increases rapidly.At the WELDING STUDS pre-opened hole place of the continuous bridge of steel and concrete structure, reinforcing bar and WELDING STUDS interweave, and bar spacing is littler, and minimum bar spacing may be less than 15mm.To the requirement (situation about can vibrating) of maximum aggregate size less than minimum bar spacing 3/4, maximum diameter of aggrogate should be less than 11mm according to Steel Concrete.Under, the situation about can not vibrate so little, directly use the self-compacting mortar of non-coarse aggregate more suitable in bar spacing.

Self-compacting mortar also can be referred to as the grouting material, and the grouting material is widely used in the back-grouting that industrial equipments is installed.But these grouting material often use special cement and special fine aggregate, and price comparison is expensive; On the other hand, these grouting expect that often the degree of mobilization loss is very fast, require more to be not suitable for more large batch of mixing and conveying with mixing with usefulness.

Summary of the invention

The objective of the invention is to propose a kind ofly have compensate for shrinkage or microdilatancy function, and cheap mortar, can be used for the self compacting high strength mortar that steel reinforced concrete bridge pre-opened hole is built.

The self compacting high strength mortar that the present invention proposes is made up of cement, stone flour, silicon ash, swelling agent, water reducer, and the weight percent of each component is:

Weight percentages of components

Cement 20%～30%

Stone flour 8%～12%

Silicon ash 1.2%～2.1%

UEA swelling agent 2%～4.5%

Diameter is 0～2.5mm yellow ground 32%～48%

Water reducer 0.50%～0.84%

Water 6.8%～13.6%,

Its total amount satisfies 100%.

Among the present invention, described cement is a kind of of silicate cement or normal silicate.

Among the present invention, described stone flour is a dry powder, or is called water-ground limestone, or is called calcite in powder, and fineness is 300 orders.

Among the present invention, described water reducer is a polycarboxylate dehydragent.

Preparation method of the present invention can be divided into following 2 kinds:

(1) interim preparation method: accurately take by weighing raw material in proportion,, yellow ground, cement, stone flour, silicon ash and UEA swelling agent are added mixing machine with water reducer and water mixing for standby use, do and stirred 1-3 minute, the water that will be mixed with water reducer then joins in the stirrer, stirs 2～4 minutes, promptly gets desired product.Interim preparation method is suitable for the situation of using in enormous quantities, both can on-the-spot prepare, and also can use (shipment distance was less than 1 hour) by transporting the building site to after factory's preparation.

(2) prefabricated dry-mixed mortar method: accurately take by weighing raw material in proportion, yellow ground need be passed through drying treatment, then yellow ground, cement, stone flour, silicon ash and UEA swelling agent are added in the mixing machine, stirred 10～20 minutes, make dry blend, carry out quantitative package according to certain specification, packing must have moisture-proof function.Using the scene, dry blend, water, water reducer are mixed in proportion in the stirrer, mix with electric blender, promptly get desired product.

The present invention is with respect to the grouting material in market, and is cheap, easy to use, is convenient to mix more in enormous quantities, carry; If desired, also can make double pack Preblend, use after the mix at the scene.

The present invention detects through relevant department, (referring to the appendix B flowing degree of net paste of cement measuring method among the JGJ56-84 " cement water reducing agent quality standard and test method "), its degree of mobilization is greater than 20cm, degree of mobilization does not have loss substantially in 2 hours, and 28d ultimate compression strength is up to the self-compacting mortar more than 70～90MPa.

The present invention has following advantage:

1, because self-compacting mortar of the present invention has higher flowability, need not to vibrate, can directly build moulding, and degree of mobilization is through time loss little (degree of mobilization in 2 hours remains unchanged substantially), mortar strength is particularly suitable for the skeleton construction of close arrangement of reinforcement up to 70～90MPa.

2, because the present invention has adopted silicate cement and ordinary Portland cement and common yellow ground, greatly reduce the cost of mortar.

3, because starting material of the present invention all adopt mass-produced commercially available finished product,, be suitable for widespread use so starting material are easy to get.

Embodiment

Below in conjunction with embodiment technical scheme of the present invention is further described.All sample moulding are not all inserted reality or are vibrated, and only need scrape plane surface and get final product.

Embodiment 1: the self compacting high strength mortar that uses the ordinary Portland cement preparation.Starting material and specification see Table 1, and material mixture ratio and performance see Table 2.

Table 1

Material	The specification or the trade mark	The source
Material	The specification or the trade mark	The source	Cement	The general silicon silicate cement of PO42.5	Shanghai sea dog Cement Group
The silicon ash	EM920U	Dust is agree international trade Shanghai company limited	Cement	The general silicon silicate cement of PO42.5	Shanghai sea dog Cement Group
The silicon ash	EM920U	Dust is agree international trade Shanghai company limited	Stone flour	Dry powder, ice-bound board	Changxing Li Jiaxiang Feng Hua micro mist factory
Swelling agent	UEA	Shanghai Newman building material factory	Stone flour	Dry powder, ice-bound board	Changxing Li Jiaxiang Feng Hua micro mist factory
Swelling agent	UEA	Shanghai Newman building material factory	Yellow ground	Cross the 2.5mm sieve	Common yellow ground
Water reducer	PC new concrete high efficiency water reducing agent; The pH value is neutral; Solid content 40%; Viscosity (being coated with-4 glasss) 40s	Aoshen Building Chemical Science ﹠ Technology Co., Ltd., Shanghai	Yellow ground	Cross the 2.5mm sieve	Common yellow ground

Table 2 uses the self compacting high strength mortar and the comparative example thereof of ordinary Portland cement preparation

Project		Proportioning 1	Comparative example
Project		Proportioning 1	Comparative example	Material usage weight percent %	Cement	22.3	25
Stone flour	12	0			Cement	22.3	25
Stone flour	12	0	The silicon ash		1.2	0
The UEA swelling agent	3	0	The silicon ash		1.2	0
The UEA swelling agent	3	0	Yellow ground		48	75
Water reducer	0.5	0	Yellow ground		48	75
Water reducer	0.5	0	Water		13	12.5
Performance	Degree of mobilization (2 hours)/cm	22(21)	Water		13	12.5	Jumping table degree of mobilization 16
	Degree of mobilization (2 hours)/cm	22(21)	Ultimate compression strength/MPa	71	54		Jumping table degree of mobilization 16
	Folding strength/	12	Ultimate compression strength/MPa	71	54	9
	Folding strength/	12	28d size changing rate/%	0.01	0.01	9

Embodiment 2: use the self compacting high strength mortar of silicate cement preparation, material therefor specification and manufacturer see Table 3, and material mixture ratio and performance see Table 4.

Table 3

Material	The specification or the trade mark	The source
Material	The specification or the trade mark	The source	Cement	P II 52.5R	Jia Xinjing yang edema mud
The silicon ash	EM920U	Dust is agree international trade Shanghai company limited	Cement	P II 52.5R	Jia Xinjing yang edema mud
The silicon ash	EM920U	Dust is agree international trade Shanghai company limited	Stone flour	Dry powder	Shanghai stone flour factory
Swelling agent	UEA	Shanghai Newman building material factory	Stone flour	Dry powder	Shanghai stone flour factory
Swelling agent	UEA	Shanghai Newman building material factory	Yellow ground	Cross the 2.5mm sieve	Common yellow ground
Water reducer	GLENIUM SP-8CN	The special building materials of Shanghai Mace company limited	Yellow ground	Cross the 2.5mm sieve	Common yellow ground

Table 4 uses the self compacting high strength mortar and the comparative example thereof of silicate cement preparation

Project		Proportioning 2	Comparative example
Project		Proportioning 2	Comparative example	Material usage weight percent %	Cement	30	25
Stone flour	12	0			Cement	30	25
Stone flour	12	0	The silicon ash		2	0
The UEA swelling agent	3	0	The silicon ash		2	0
The UEA swelling agent	3	0	Yellow ground		40.59	75
Water reducer	0.81	0	Yellow ground		40.59	75
Water reducer	0.81	0	Water		11.6	12.5
Performance	Degree of mobilization (2 hours)/cm	21(21)	Water		11.6	12.5	Jumping table degree of mobilization 16
	Degree of mobilization (2 hours)/cm	21(21)	Ultimate compression strength/MPa	85	58		Jumping table degree of mobilization 16
	Folding strength/	13	Ultimate compression strength/MPa	85	58	10
	Folding strength/	13	28d size changing rate/%	0.02	0.01	10

Embodiment 3: use ordinary Portland cement, according to prefabricated dry-mixed mortar method preparation self compacting high strength mortar.Specifications of raw materials sees Table 5, and the dry powder proportioning sees Table 6.

Table 5

Material	The specification or the trade mark	The source
Material	The specification or the trade mark	The source	Cement	PO 42.5	Shanghai Cement Plant
The silicon ash	EM920U	Dust is agree international trade Shanghai company limited	Cement	PO 42.5	Shanghai Cement Plant
The silicon ash	EM920U	Dust is agree international trade Shanghai company limited	Stone flour	Dry powder	Shanghai stone flour factory
Swelling agent	UEA	Hua Lian, Shanghai admixture factory	Stone flour	Dry powder	Shanghai stone flour factory
Swelling agent	UEA	Hua Lian, Shanghai admixture factory	Yellow ground	Cross the 2.5mm sieve	Common yellow ground, oven dry
Water reducer	GLENIUM SP-8CN	The special building materials of Shanghai Mace company limited	Yellow ground	Cross the 2.5mm sieve	Common yellow ground, oven dry

Table 6 uses the dry powder proportioning of the self compacting high strength mortar of silicate cement preparation

Material	Consumption weight percent %	Remarks
Material	Consumption weight percent %	Remarks	Cement	30	All dried ingredients are pre-mixed evenly becomes dry powder
Stone flour	12		Cement	30
Stone flour	12	The silicon ash	2.1
The UEA swelling agent	4.5	The silicon ash	2.1
The UEA swelling agent	4.5	Yellow ground	38.9

Water	10.4
Water	10.4		Water reducer	0.84

Dry powder, water, water reducer are added in the stirrer, mix, build sample then with electric blender.Mortar performance sees Table 7.

Table 7

Performance project	Numerical value
Performance project	Numerical value	Degree of mobilization (2 hours)/cm	23(22)
Ultimate compression strength/MPa	92	Degree of mobilization (2 hours)/cm	23(22)
Ultimate compression strength/MPa	92	Folding strength/	13.5
28d size changing rate/%	0.02	Folding strength/	13.5

Claims

1, a kind of self compacting high strength mortar is characterized in that being made up of cement, stone flour, silicon ash, swelling agent, water reducer, and the weight percent of each component is: