AGREEMENT OF LIMITED PARTNERSHIP OF REDI-MIX, L.P.

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Exhibit 3.28c

AGREEMENT OF LIMITED PARTNERSHIP

OF

REDI-MIX, L.P.

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.
.
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AGREEMENT OF LIMITED PARTNERSHIP
OF
REDI-MIX, L.P.

TABLE OF CONTENTS

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Page
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ARTICLE 1................................................................ 1
1.1 Definitions..................................................... 1
1.2 References...................................................... 7

ARTICLE 2................................................................ 7
2.1 Formation of the Limited Partnership............................ 7
2.2 Partnership Name................................................ 7
2.3 Purpose......................................................... 7
2.4 Principal and Registered Office................................. 7
2.5 Term of the Partnership......................................... 7

ARTICLE 3................................................................ 7
3.1 Initial Capital Contribution of General Partner................. 8
3.2 Initial Capital Contribution of Limited Partners................ 8
3.3 Authorization of Partner Loans.................................. 8
3.4 Additional Capital Contributions................................ 8

ARTICLE 4................................................................ 8
4.1 Distribution of Net Cash Flow................................... 8
4.2 Distribution of Net Proceeds of a Capital Transaction........... 8
4.3 Return of and Interest on Capital Contributions................. 8
4.4 Payments........................................................ 8
4.5 In-Kind Distributions........................................... 9
4.6 Allocations of Net Profit and Net Loss.......................... 9
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4.7 Partnership Minimum Gain Chargeback............................. 10
4.8 Minimum Gain Chargeback for Partner Nonrecourse Debt............ 10
4.9 Qualified Income Offset......................................... 10
4.10 Limit on Loss Allocations....................................... 11
4.11 Net Loss from Partner Nonrecourse Debt.......................... 11
4.12 Nonrecourse Deductions.......................................... 11
4.13 Code Section 754 Adjustments.................................... 11
4.14 Reversal of Mandatory Allocations............................... 11
4.15 Compliance with Code............................................ 11
4.16 Tax Allocations -- Code Section 704(c).......................... 11
4.17 Allocation on Transfer.......................................... 12
4.18 Minimum Interest of General Partner............................. 12

ARTICLE 5................................................................ 12
5.1 Capital Accounts................................................ 12
5.2 Adjustment for In-Kind Distributions............................ 12
5.3 Property Revaluation............................................ 13
5.4 Interpretation.................................................. 13
5.5 Obligation to Repay or Restore.................................. 13
5.6 Tax Elections................................................... 14

ARTICLE 6................................................................ 14
6.1 Operating Expenses and Reimbursements........................... 14

ARTICLE 7................................................................ 14
7.1 Admission of Additional Partners................................ 14
7.2 Assignment or Transfer of Partnership Interests................. 14

ARTICLE 8................................................................ 14
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8.1 Powers of General Partner....................................... 14
8.2 Authority as to Third Persons................................... 17
8.3 Compensation and Expenses of the General Partner................ 17
8.4 Covenants of the General Partner................................ 17
8.5 Limitations on Authority........................................ 18
8.6 No Withdrawal From Partnership.................................. 18
8.7 Officers........................................................ 18

ARTICLE 9................................................................ 18
9.1 Dissolution..................................................... 18
9.2 Continuation.................................................... 18
9.3 Events Affecting a Limited Partner.............................. 19
9.4 Liquidation Procedures.......................................... 19
9.5 Termination..................................................... 20
9.6 No Petition for Dissolution..................................... 20
9.7 Compliance with Timing Requirements of Treasury Regulations..... 20

ARTICLE 10............................................................... 20
10.1 Financial and Tax Accounting and Reports........................ 20
10.2 Valuation....................................................... 20
10.3 Supervision; Inspection of Books................................ 20
10.4 Consent in Lieu of Meeting...................................... 21
10.5 Withholding..................................................... 21

ARTICLE 11............................................................... 21
11.1 Execution and Filing of Documents............................... 21
11.2 Other Instruments and Acts...................................... 21
11.3 Binding Agreement............................................... 21
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11.4 Governing Law................................................... 21
11.5 Notices......................................................... 21
11.6 Power of Attorney............................................... 22
11.7 Amendment....................................................... 22
11.8 Entire Agreement................................................ 23
11.9 Titles; Subtitles............................................... 23
11.10 Exculpation..................................................... 23
11.11 Indemnification of the General Partner.......................... 23
11.12 Limitation of Liability of the Limited Partners................. 23
11.13 Ambiguities..................................................... 23
11.14 No Right to Partition........................................... 24
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AGREEMENT OF LIMITED PARTNERSHIP
OF
REDI-MIX, L.P.

THIS AGREEMENT OF LIMITED PARTNERSHIP, made and entered into as of this
_____ day of April, 1999, by and between Redi-Mix Management, Inc., a Texas
corporation (the "General Partner") and Atlas Investments Inc., a Nevada
corporation (the "Limited Partner").

NOW, THEREFORE, the General Partner and the Limited Partner hereby agree to
the terms and conditions of this Agreement of Limited Partnership as follows:

ARTICLE 1.

DEFINITIONS; REFERENCES

1.1 Definitions. Unless the context requires otherwise, the following terms
shall have the meanings specified in this Section 1.1:

1.1.1 Act: The Texas Revised Limited Partnership Act.

1.1.2 Additional Capital Contributions: The additional capital
contributions described in Section 3.4.

1.1.3 Adjusted Capital Account Deficit: With respect to any Partner, the
deficit balance, if any, in such Partner's Capital Account as of the
end of the relevant taxable year, after giving effect to the following
adjustments:

(a) Credit to such Capital Account any amounts which such Partner (1)
is obligated to restore to the Partnership upon liquidation of
its interest in the Partnership (or which is so treated pursuant
to Regulations Section 1.704-1(b)(2)(ii)(c)) pursuant to the
terms of this Agreement or under state law or (2) is deemed to be
obligated to restore pursuant to the penultimate sentences of
Regulations Sections 1.704-2(g)(1) and 1.704-2(i)(5) and (3) the
Partner's share (as determined under Code Section 752) of any
recourse indebtedness of the Partnership to the extent that such
indebtedness could not be repaid out of the Partnership's assets
if all of the Partnership's assets were sold at their respective
Book Values as of the end of the Fiscal Year or other period and
the proceeds from the sales were used to pay the Partnership's
liabilities; and

(b) Debit to such Capital Account the items described in Sections
1.704-1(b)(2)(ii)(d)(4), 1.704-1(b)(2)(ii)(d)(5), and
1.704-1(b)(2)(ii)(d)(6) of the Regulations.

The foregoing definition of Adjusted Capital Account Deficit is
intended to comply with the provisions of Section 1.704-1(b)(2)(ii)(d)
of the Regulations and shall be interpreted consistently therewith.
For purposes of clause (a)(3) above, the amounts computed pursuant to
clause (a)(1) above for each Partner shall be


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considered to be proceeds from the sale of the assets of the
Partnership to the extent such amounts would be available to satisfy
(directly or indirectly) the indebtedness specified in clause (a)(3).

1.1.4 Affiliate: With respect to any Person, a Person that directly or
indirectly, through one or more intermediaries, controls, is
controlled by, or is under common control with the Person in question.
As used herein, the term "control" means the possession, directly or
indirectly, of the power to direct or cause the direction of the
management and policies of a Person, whether through ownership of
voting securities or interests, by contract, or otherwise.

1.1.5 Agreement: This Agreement of Limited Partnership of Redi-Mix, L.P.
and any amendments hereto.

1.1.6 Bankruptcy: A Person shall be deemed bankrupt if:

(a) any proceeding is commenced against such Person as "debtor" for
any relief under bankruptcy or insolvency laws, or laws relating
to the relief of debtors, reorganizations, arrangements,
compositions, or extensions and such proceeding is not dismissed
within sixty (60) days after such proceeding has commenced, or

(b) such Person commences any proceeding for relief under bankruptcy
or insolvency laws or laws relating to the relief of debtors,
reorganizations, arrangements, compositions, or extensions.

1.1.7 Book Value: With respect to any asset, the asset's adjusted basis for
federal income tax purposes, except as follows:

(a) the initial Book Value of any asset contributed (or deemed
contributed under Regulations Section 1.708-1(b)(1)(iv)) by a
Partner to the Partnership shall be the asset's gross fair market
value at the time of the contribution;

(b) the Book Value of all Partnership assets shall be adjusted to
equal their respective gross fair market values, as determined by
the General Partner in its reasonable judgment:

(i) if the General Partner reasonably determines an adjustment
is necessary or appropriate to reflect the relative economic
interests of the Partners in the Partnership as of (1) the
acquisition of an additional interest in the Partnership by
any new or existing Partner in exchange for more than a de
minimis capital contribution, or (2) the distribution by the
Partnership to a Partner of more than a de minimis amount of
Partnership property as consideration for an interest in the
Partnership; and


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(ii) as of the liquidation of the Partnership within the meaning
of Regulations Section 1.704-1(b)(2)(ii)(g);

(c) the Book Value of any Partnership asset distributed to any
Partner will be the gross fair market value of the asset on the
date of distribution; and

(d) the Book Values of Partnership assets will be increased or
decreased to reflect any adjustment to the adjusted basis of the
assets under Code Sections 734(b) or 743(b), but only to the
extent that the adjustment is taken into account in determining
Capital Accounts under Regulations Section 1.704-1(b)(2)(iv)(m),
provided that Book Values will not be adjusted hereunder to the
extent that the General Partner determines that an adjustment
under clause (b) is necessary or appropriate in connection with a
transaction that would otherwise result in an adjustment under
this clause (d).

After the Book Value of any asset has been adjusted under clause (a),
clause (b) or clause (d) above, Book Value will be adjusted by the
Depreciation taken into account with respect to the asset for purposes
of computing Net Profit and Net Loss.

1.1.8 Capital Account: The capital account of a Partner established and
maintained in accordance with Section 5.1.

1.1.9 Capital Contributions: With respect to any Partner, the amount of
money actually contributed (or deemed contributed pursuant to
Regulations Section 1.704-1(b)(2)(iv)(c)) to the Partnership and the
initial Book Value of any property (other than money) contributed to
the Partnership with respect to the interest in the Partnership held
by that Partner (net of any liabilities secured by such property that
the Partnership is considered to assume or to take subject to Code
Section 752). Any reference in this Agreement to the Capital
Contribution of a Partner will include a Capital Contribution made by
any prior Partner with respect to the Partnership interest of the
Partner.

1.1.10 Capital Transaction: The sale, exchange or other disposition of all
or any portion of the property of the Partnership other than in the
ordinary course of business of the Partnership. Capital Transactions
include the financing or refinancing of Partnership property which
creates excess funds not needed for Operations and which funds, in the
opinion of the General Partner, are available for distribution to the
Partners.

1.1.11 Code: The United States Internal Revenue Code of 1986, as now
existing or hereafter amended. References to sections of the Code
include successor provisions to those sections.

1.1.12 Depreciation: For each taxable year or other period, an amount equal
to the depreciation, amortization or other cost recovery deduction
allowable with respect to an asset for the year or other period,
except that if the Book Value of an asset


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differs from its adjusted basis for federal income tax purposes at the
beginning of the year or other period, Depreciation will be an amount
which bears the same ratio to the beginning Book Value as the federal
income tax depreciation, amortization or other cost recovery deduction
for the year or other period bears to the beginning adjusted tax
basis, provided that if the federal income tax depreciation,
amortization, or other cost recovery deduction for the year or other
period is zero, Depreciation will be determined with reference to the
beginning Book Value using any reasonable method selected by the
General Partner.

1.1.13 Fiscal Year: The period commencing on January 1 of each year and
ending on December 31 of such year.

1.1.14 General Partner: Redi-Mix Management, Inc., a Texas corporation.

1.1.15 Gross Income: For each Fiscal Year or other period, an amount equal
to the Partnership's gross income as determined for federal income tax
purposes for such Fiscal Year or period but computed with the
adjustments specified in Section 1.1.20(a) and (c).

1.1.16 Initial Capital Contributions: The Capital Contributions of the
General Partner made pursuant to Section 3.1 and the Limited Partners
made pursuant to Sections 3.2 and 3.3.

1.1.17 Limited Partner: Atlas Investments Inc., a Nevada corporation, and
each Person who is admitted to the Partnership as a Limited Partner
and shown as a Limited Partner on the books and records of the
Partnership.

1.1.18 Net Cash Flow: All cash funds from operations of the Partnership on
hand or on deposit from time to time after (i) payment of all
operating expenses payable as of the date in question, (ii) provision
for payment of all outstanding and unpaid Partnership obligations due
and payable as of the date in question or within sixty (60) days
thereafter, and (iii) the establishment of such reasonable reserves as
the General Partner, in its sole discretion, deems appropriate for the
operating needs of the Partnership. "Net Cash Flow" shall not include
or reflect any proceeds received or expenses incurred in connection
with a Capital Transaction.

1.1.19 Net Proceeds of a Capital Transaction: The net proceeds received by
the Partnership in connection with a Capital Transaction after payment
of all costs and expenses incurred by the Partnership in connection
with such Capital Transaction, including, without limitation, brokers'
commissions, loan fees, other closing costs, the cost of any
alteration, improvement, restoration or repair of Partnership assets
necessitated by or incurred in connection with such Capital
Transaction, any reserves that the General Partner believes in good
faith should be established and the payment of any loans owed by the
Partnership to any of the Partners, plus any other loans that should
be appropriately paid, as determined by the General Partner in its
reasonable discretion.


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1.1.20 Net Profit and Net Loss: For each Fiscal Year or other period, an
amount equal to the Partnership's taxable income or loss for such
Fiscal Year or period, determined in accordance with Code Section
703(a) (for this purpose, all items of income, gain, loss or deduction
required to be stated separately pursuant to Code Section 703(a)(1)
shall be included in taxable income or loss) with the following
adjustments:

(a) any income of the Partnership that is exempt from federal income
tax and not otherwise taken into account in computing Net Profit
or Net Loss shall be added to such taxable income or loss;

(b) any expenditures of the Partnership described in Code Section
705(a)(2)(B) or treated as Code Section 705(a)(2)(B) expenditures
under Regulations Section 1.704-1(b)(2)(iv)(i) and not otherwise
taken into account in computing Net Profit or Net Loss shall be
subtracted from such taxable income or loss;

(c) gain or loss resulting from any disposition of Partnership
property with respect to which gain or loss is recognized for
federal income tax purposes shall be computed by reference to the
Book Value of such property notwithstanding that the Book Value
of such asset differs from its adjusted tax basis;

(d) gain or loss resulting from any adjustment pursuant to Section
1.1.7(b) shall be taken into account as gain or loss from
disposition of the asset for purposes of computing Net Profit or
Net Loss hereunder;

(e) gain or loss resulting from any adjustment attributable to an
in-kind distribution of assets to any Partner pursuant to
Sections 5.2 shall be taken into account as gain or loss from
disposition of the asset for purposes of computing Net Profit or
Net Loss hereunder;

(f) in lieu of the depreciation, amortization and other cost recovery
deductions taken into account in computing taxable income or
loss, there shall be taken into account Depreciation for such
Fiscal Year or other period as determined under Regulations
Section 1.704-1(b)(2)(iv)(g)(3);

(g) the amount of any Gross Income specially allocated to the
Partners pursuant to Sections 4.7 through 4.9 and 4.14 shall not
be included as income or revenue; and

(h) any amount allocated pursuant to Sections 4.11 through 4.14 shall
not be included as a gain, loss or deduction.

1.1.21 Net Profit and Net Loss from Capital Transactions: Net Profit and
Net Loss including only those items of income, gain, loss and
deduction relating to Capital Transactions.


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1.1.22 Net Profit and Net Loss from Operations: Net Profit and Net Loss
excluding those items of income, gain, loss and deduction related
solely to Capital Transactions.

1.1.23 Nonrecourse Deductions: Losses, deductions or Code Section
705(a)(2)(B) expenditures attributable to Nonrecourse Liabilities of
the Partnership. The amount of Nonrecourse Deductions for any Fiscal
Year or other period shall be determined in accordance with the
provisions of Regulations Section 1.704-2(c).

1.1.24 Nonrecourse Liability: A nonrecourse liability as defined in
Regulations Section 1.752-1(a)(2).

1.1.25 Operations: All operations and activities of the Partnership other
than those related to or consisting of a Capital Transaction.

1.1.26 Partner: A Partner of the Partnership, including the General Partner
and the Limited Partner.

1.1.27 Partner Nonrecourse Debt: Any Nonrecourse Liability of the
Partnership for which any Partner or related person bears the economic
risk of loss under Regulations Section 1.752-2.

1.1.28 Partner Nonrecourse Debt Minimum Gain: The minimum gain attributable
to Partner Nonrecourse Debt as determined under Regulations Section
1.704-2(i)(3).

1.1.29 Partner Nonrecourse Deductions: Partnership losses, deductions or
Code Section 705(a)(2)(B) expenditures attributable to a particular
Partner Nonrecourse Debt. The amount of Partner Nonrecourse Deductions
for any Fiscal Year or other period shall be determined in accordance
with the provisions of Regulations Section 1.704-2(i)(2).

1.1.30 Partnership: Redi-Mix, L.P., a Texas limited partnership.

1.1.31 Partnership Certificate: The certificate of limited partnership of
the Partnership filed in conformance with the Act.

1.1.32 Partnership Minimum Gain: The amount computed under Regulations
Section 1.704-2(d)(l) with respect to the Partnership's Nonrecourse
Liabilities.

1.1.33 Partnership Percentage or Percentages: The percentages of the
Partners as follows:

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General Partner .1%
Limited Partner 99.9%
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1.1.34 Partnership Term: The period of duration of the Partnership, as set
forth in Section 2.5.

1.1.35 Person: Any individual, partnership, corporation, trust or other
legal entity.


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1.1.36 Regulations: The Income Tax Regulations promulgated under the Code,
as such regulations may be amended from time to time (including
corresponding provisions of succeeding regulations).

1.1.37 Tax Matters Partner: The General Partner.

1.1.38 Transfer: Any sale, assignment, transfer, lease or other disposal of
property, including without limitation, an interest in the
Partnership.

1.2 References. Unless otherwise specified herein, references in this Agreement
to "Section," "Subsection," "Article," or "Exhibit" refer to the sections,
subsections, articles, or exhibits in this Agreement.

ARTICLE 2.

FORMATION, NAME, PURPOSE, REGISTERED OFFICE,
REGISTERED AGENT AND TERM

2.1 Formation of the Limited Partnership. The General Partner and the Limited
Partner hereby form the Partnership as a limited partnership pursuant to
and in accordance with the provisions of the Act.

2.2 Partnership Name. The business of the Partnership will be conducted under
the name Redi-Mix, L.P. or such other name or names as the General Partner
may determine.

2.3 Purpose. The purpose of the Partnership is to (i) manufacture and
distribute concrete and related products, (ii) own, manage, operate,
mortgage, sell and otherwise deal with the assets of the Partnership; and,
(iii) engage in such other activities as the General Partner shall deem
appropriate, to the extent such activities may be carried on under
applicable law and are not prohibited by the terns and provisions of this
Agreement.

2.4 Principal and Registered Office. The principal office of the Partnership is
at 1445 MacArthur, Ste. 136, Carrollton, Texas 75007. The General Partner
has a business office at the Partnership's principal office. The registered
office of the Partnership is at 1445 MacArthur Drive, Suite 136,
Carrollton, Texas 75007, and John C. Miller is the registered agent of the
Partnership. The General Partner may change the principal or registered
office or registered agent of the Partnership from time to time. The
General Partner may establish, maintain and abandon one or more additional
places of business for the Partnership.

2.5 Term of the Partnership. The term of the Partnership shall commence upon
the filing and recording of the Partnership Certificate, and shall continue
until December 31, 2050, unless earlier terminated pursuant to the terms of
this Agreement.

ARTICLE 3.

CAPITAL CONTRIBUTIONS; PARTNER LOANS


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3.1 Initial Capital Contribution of General Partner. The General Partner has
contributed $1.00 to the Partnership. The General Partner shall not
otherwise be required to make additional contributions to the Partnership
except as provided in Sections 3.4 and 5.5.

3.2 Initial Capital Contribution of Limited Partners. The Limited Partner has
contributed $999.00 to the Partnership hereto. The Limited Partner shall
not be required to make additional contributions to the Partnership except
as specified in Sections 3.4 and 5.5.

3.3 Authorization of Partner Loans. Subject to the limitations herein and to
other agreements of the Partnership, the General Partner from time to time
may cause the Partnership to borrow required amounts from one or more
Partners or their Affiliates. Loans made by Partners or Affiliates under
this Section 3.3 will not be considered a contribution to the capital of
the Partnership, but will constitute indebtedness of the Partnership to the
advancing Partner or Affiliate, payable from the first available net cash
flow of the Partnership unless otherwise agreed by the lending Partner or
Affiliate and, to the extent still unpaid, upon the termination and
liquidation of the Partnership. Each loan by a Partner or Affiliate will
bear simple interest compounded annually on the unpaid principal balance at
the interest rate approved by the General Partner. The Partners will not be
personally liable for loans made by Partners or Affiliates under this
Section 3.3 or be obligated to make contributions to the capital of the
Partnership to repay those loans. Loans made by Partners or Affiliates
under this Section 3.3 will be payable only from the assets of the
Partnership.

3.4 Additional Capital Contributions. The Partners may make Additional Capital
Contributions to the Partnership from time to time as may be required to
meet the demands of the business of the Partnership. The Partners shall
contribute such Additional Capital Contributions in cash in proportion to
the Partners' Partnership Percentages.

ARTICLE 4.

DISTRIBUTIONS AND ALLOCATIONS

4.1 Distribution of Net Cash Flow. Net Cash Flow shall be distributed among the
Partners in accordance with their Partnership Percentages at such times and
in such amounts as shall be determined by the General Partner.

4.2 Distribution of Net Proceeds of a Capital Transaction. Net Proceeds of a
Capital Transaction shall be distributed among the Partners in accordance
with their Partnership Percentages at such times and in such total amounts
as shall be determined by the General Partner.

4.3 Return of and Interest on Capital Contributions. No Partner is entitled to
the return of his Capital Contributions or his Capital Account or to be
paid interest in respect of either his Capital Account or any Capital
Contribution made by him to the Partnership except as provided in this
Agreement.

4.4 Payments. The amount of any distribution or payment to a Partner whether
pursuant to Article 4 or Article 9 hereof may be made in cash or in-kind or
partially in cash and


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partially in-kind in the reasonable discretion of the General Partner or
the liquidating trustees, as the case may be, less reasonable reserves
established in the reasonable discretion of the General Partner or the
liquidating trustees, as the case may be, for known or unknown liabilities
of the Partnership.

4.5 In-Kind Distributions. All distributions of assets in-kind shall be made at
Book Value as determined pursuant to Section 5.3 and shall be distributed
to the Partners in the same manner as a distribution of Net Proceeds of a
Capital Transaction would have been made if such assets had been sold. The
Net Profit or Net Loss resulting from distribution will be allocated in
accordance with Section 4.6.3 or Section 4.6.4, as the case may be.

4.6 Allocations of Net Profit and Net Loss.

4.6.1 Net Profit From Operations.

(a) If any Net Loss has been allocated to the Partners pursuant to
Section 4.6.2 or Section 4.6.4, then Net Profit from Operations
shall first be allocated to the Partners, in the same proportions
as such Net Loss was allocated, until each Partner's Capital
Account balance equals what it would have been had there been no
such allocation of Net Loss.

(b) After any allocation required pursuant to Section 4.6.1(a), Net
Profit from Operations shall be allocated among the Partners in
accordance with their Partnership Percentages